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Philofophical
A S ~k~kA .
EXPERIMENTS
AND
OBSERVATIONS
Of the late Eminent
Dr, ROBERT HOOKE,
S, R, S,
And Geom. Pro£ Grejh,
. \; AND
Other Eminent Virtuoso’s in his Time.
With COPPER PLATES,
Publifh’d by W. Derham, F. R. S.
/ LONDON:
Printed by W. and J. I n n y s, Printers to the Royal Socie t y, at the Weft End of At. Paul’s.
MDCGXXVI.
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T O
The Right Honourable
J U LI A N 4
Count ess-Do wage r.
o F
BURLING T O N,
This Collection of Paper st
As well for her Perianal Virtues and Merits,, as for her fingular Favours to me, are? with greateft RcfpeCi and Gratitude* hum¬ bly dedicated by
Her Ladyfbifs Mojl obliged Humble Servant^
W. D E R H A M.
4
AMENDMENTS.
PAG. i Infert in the Margin at 1. 14. V. Poft Works . p. 564.
P. 226. 1 ,ult. after loofe, add in the fame manner . P.227. 1. 4. for Tab. III. read I. Ib. 1. 27. read Weight K K„ lb. 1. 29, 30. re Book E F. Gthe King to be hung on the Hook F. P. 228. 1. 3 1 . lor believed , r. received. P.230 .ult. r. Height. P. 231. 1. 25,26. r. Height. P. 233. 1. antepen. r. Tab. I. P. 234. 1. 17. r. thefe . Ib. 1. penult^ after left add, and by that Means. P.23 7* 1. 3, after Stick add, [mailer , and tapering upwards towards great D, which is an hollow very light Ball of Wood . Ib. 1. 26. read Tab. II. P, 238. 1, penult, r. Tab. I. P. 239, 1. 12. r. Tab. I. Ib. I. 20. r. proportion . P. 240. 1. 4. for fos r. by. Ib, 1. i8» after or add that. P. 321. 1, 28. r .Condore. P. 328. 1. 16. r. abiegno . P. 336. I. 17. r. lignum- Aloes* Civet f Storax v* La- danum a P„ 245* 1. 5, read meat
TO THE
READE R.
H E principal Author of thefe ‘Papers being a Per - fin of great Repute , 1 thought the Publication of them would be very ac¬ ceptable to the Curious ; and therefore was wil¬ ling to undertake the Work , although 1 found it would be very laborious , by reafin the Papers were very numerous , and in great Confujion .
After ‘Dr . Hook’j* Death, both his Pa¬ pers , of his Figures and Modules
{hut I fear not nearly all) fell into the Elands of my ingenious friend Richard Waller, Efq\ out of which he file died tbofe that he pub ~ lifhed in 1705 ; and intended others for the Prefs : But dying before he had accompli fe¬ ed that Defign , a Part of the Papers were en-
trufied
To the Reader.
*
trufted to me , by Mr. Waller’/ Lady , and Jonathan Blackwell, Efq\ In which I expelled great Matters from fuch illuflrious Names* as I found among them : But when I came to per ufe , and examine them , I found only here and there fome, that anfwered my Ex¬ pectation ; which the Reader hath in the following Collection. In which he may pro¬ bably expelt fome of the many Lectures, which the Doctor read in Grelham College, and thofe of Sir John Cutler’/ Infiitution . But the beft of thefe Dr. Hook himfelf or Mr. Waller puhlifhed : So that what I have in my Hands , will be of little Ufe to the learned World, mo ft of them feem to have been intended by the Doctor , for half an Hour s Amu foment to a fmall Auditory , ra¬ ther than for the Brefs.
As for Order , or Method, little could be obferved in fuch a confufed Variety of Sub¬ jects , as thefe Bapers contain. And there - fore the beft I could do, was to rank them , as near as I could, according to the Order of the lime in which they were wr itten, or communicated.
And as for other Bapers interfperfed with Dr. HookV, they are , for the mo ft part, of fuch confiderable Berfons, that the Reader will expeCt no Ex cafe for my infert « ing of them.
But if any remarkable Obfcurities or Im¬ perfections Jhould be met with , it is what I could not help , by reafon fome of the Bapers
were
*
\
To the Reader.
were torn, feme obliterated \ fome written in an Hand fcarce legible, &c. and I was not minded to give my own Senfe , left it fhould be thought that I had impofed my own , tu¬ ft e ad of the feveral ingenious Hut hors Senfe s .
But after all , many of thofe Imperfec¬ tions, and Obfcurities , are owing to the Mifcarriage of fome of the Papers , which either never came to Mr, WallerV Hands , or, if they did, were loft , or miftaid , before they came to mine, the ‘Papers being put in¬ to different Hands , after Mr. Waller\r Heath .
whereas Figures, Modules, would have explained divers of the Papers, that are publijhed, and have enabled me to have imparted others , altogether as valuable % but finding few, or none, but what are here publijhed, neither among the Papers them- felves, nor in the Repofitory , nor Papers of the Royal Society, I was forced to be con * tent .
For a Conclufion of this Preface, I Jhall anfwer two Ac cu fat ions that have been, or may be charged upon me : One k, That I have long detained thefe Papers from the Publick : The other, that I have engaged myfelf in Matters lying out of my IV ay. To both which, one Anfwer may ferve , namely. That I have made the collecting , and puhlijhing thefe Papers, my Hiverfion, at Leifure Hours : By which Means, and by reafon the Papers y out of which thefe
were
To the Reader.
were felebled , were very numerous , and many of them came late to my Hands , their Pub¬ lication hath been the longer delay'd . And as for the Pjiverjity of this from the Bufi- nefs of my Profejjlon : I confefs it is not dir ell \ Divinity , but yet 1 think it , by no Means , unfit for a Clergy-man' s PDiverfion . iw as it is necejfary for a Clergy-man (as well as others) fome times to divert , <00^ un¬ bend his Mind, from his more ferious Stu¬ dies , fo what ‘Diverfion more innocent , proper, than that which promotes Know¬ ledge , Experience, and is a IDifcovery
{if never fo fin all) of any of the JVorks of the infinite Creator ? To the promoting which End, the Publication of the fe Papers was, in fome Me a jure, intended by
W, Derham.
( I )
CURIOUS
PHILOSOPHICAL
Cbfervations and Experiments
Dr. ROBERT HOOK ,
A N D
Other Eminent V irtuoso’s in his
1 line.
Of the Invention of the Barometer
in the Tear 1659.
N one of Dr. HooTs Papers (not here publifh- ed3 becaufe imperfedl) I find this Remark ? vi%„ The Inftrument ^ for finding the different Prefire of Air upon the Parts ofi the Earth fubjacenty mas ' fir ft ohferved by the Honourable Mr. Boyle, who, upon theSuggeftion of Sir Chriftopher Wren, erecting a Tube of Glafsfio filled with Mercury, as is now ^ ° L- ^ B uf natty
% Of the Invention of
ii finally done in the common Barometer , in order to find outj whether the Prejfure of the Moon , accord¬ ing to the Cartefian Hypothefis , did affeft the Air ; inftead of finding the Fluctuation which might caufe the Phenomena of the Tides , dif covered the Vari¬ ation of its Prejfure to proceed from differing Caufe s , and at different Times , from what that Hypothefis would have predicted. That Propriety of the Air ffor ought appears') was never difcovered till that Time , which is not yet thirty Tears fince , &c.
T o this I IV. D, fhall add another Remark I find in the Minutes of the Royal Society , Febru¬ ary 20. 167^5 viz. Upon a Difcourfe of fome Experiments to be made with the Barometer on the Monument, it was queried , how this Experi¬ ment of the differing Prejfure of the Atmofphere came at firfl to he thought of ? And it was related , That it was firfl propounded by Sir Chrifto- pher Wren , in order to examine Monfienr des Cartes5.? Hypothefis , Whether the paffing by of the Body of the Moon did prefs upon the Air , and ccnjequently alfo upon the Body of the Water. And that the firfl Trial thereof was made at Mr. Boyles Chamber in Oxford.
The Time, whenthefe Obfervations were made, was about the Year 1658, or 59 ; at which Time: Mr. Boyle having a Barometer fixed up, for the obferving the Moon’s Influence upon the Wa¬ ters, happened to difcover the ufe of it in relati¬ on to the Weather, and to afiure himfelf, that it: was the Gravitation of the Atmofphere which kept up the Quickfilver to fuch an Height, as the learned Abroad, particularly Torricelli , had fufpedled before.
But although this Ufe of the Barofcop* is owing to Sir Chriftopher Wren , and Mr Boyle , yet, to do every Man Jullice, I fhal
giv-
the Barometer. 5
give the Hiftory of this excellent Inftrument, from the Extracts of a very ingenious Friend.
The firft Inventor of it was Torricellis at Florence , in 1643. From whence Father Merfenne brought it into France the Year fol¬ lowing, 1644.. And Monfieur Pafcal being informed of it by Monfxeur Petit, the Engi¬ neer, they both tried it in 1646, at Rouen , with the fame Succefs as it had been tried in Italy . Some Time after which, art Experiment was made with a Tube of forty fix Feet, filled with Water, and alfo with Wine : Which Experiment Monfi- eur Pafcal gave an Account of in a Piece printed in 1647 ; in which Year he was inform¬ ed of Torricelli's Solution of the Phenomenon, by the Weight of the Air j and devifed, for the examining it, the famous Experiment with two Tubes, one within the other , which he men¬ tions in a Letter written in November 1647. And laftly , in 1648 the fame Monfieur Pafcal made his Experiments on the Tops and Bottoms of Hills, Buildings, iSc. which laft Experiments Monfieur Des Cartes laid Claim to ; affirming, that he defired Monfieur Pafcal to make them two Years before, and predicted their Succefs, contrary to Monfieur Pafcal' s Sentiments.
Monfieur Azout alfo laid the fame Claim, but it is the moft probable that Monfieur Pafcal had the belt Title.
This Experiment which Torricelli made with Quickfilver, Galileo had in eftedl tried with Wa¬ ter in long Tubes by Pumping j with which he found he could never get the Water to afcend above thirty three Feet : But the Caufe he could never hit of.
After the Torricellian Experiment had been inuch celebrated in divers Places, at laft Otto de Guerrick , Gonful of Magdeburgh , was in-
B $ formed
4 Obfcrvations of the
formed of it by Father Valerian at Katisbon , who claimed it as his own Invention : But this was not till the Year 1654. After which GuericFs Experiment (called the Magdeburgh Experiment') was much talked of.
Fr o m this fhort Hiftory of the Barometer, not only the Inventor and Improvers of it appear, but in forne Meafure alfo the excellent Ufes of it : Particularly the Gravitation of the incumbent Atmofphere, (one of the nobleft philofophical Difcoveries) the Changes of the Weather, &c.
W. Derham,
The Lord Kingkardine^r Obfervations of the Pendulum Clocks at Sea , in 1662.
Th e Lord Kingkardine did refolve to make fome Trial what might be done, by car¬ rying a Pendulum Clock to Sea $ for which End, he contrived to make the Watch Part to be moved by a Spring inftead of a Weight y and then making the Cafe of the Clock very heavy with Lead, he fufpended it, underneath the Deck of the Ship, by a Ball and Socket of Brafs, making the Pendu¬ lum but fhort , namely, to vibrate half Seconds, and that he might be the better inabled to judge of the EffedF of it, he caufed two of the fame Kind of Pendulum Clocks to be made, and fuf¬ pended them both pretty near the middle of the VefTel, underneath the Deck ; thus done, ha¬ ving firft adjufted them to go equal to one another, „ and pretty near to the true Time ; he caufedi them firft to move parallel to one another, that is5 in the Plane of the Length of the Ship, and af¬ terwards he turned one to move in a Plane at Eight!
Angles;.
Pen dulum Clocks at Sea . $
Angles with the former ; and in both thefe Cafes it was found by Trials made at Sea, at which I (i.e. Dr. Hook') was prefent, that they would vary from one another,though not very much,fometimes one gain¬ ing and fometimes the other, and both of them from the true Time, but yet not fo much but that we judged they might be of very good Ufe at Sea, if fome farther Contrivances about them were thought upon, and put in Practice. This firft Trial was made in the Year 1662 ; whereupon, thefe being found to be able to continue their Mo¬ tion without flopping, feveral other Clocks of this Nature were made and fent to Sea, by fuch as fhould make farther Experiment of their Ufe. And we have an Account which was given from Sir R. Holmes , who tried them in failing from St. tthomas Weft- ward about 800 Leagues, and then tacking about fleer’d about 3 00 Leagues N. N. E. towards the Coaft of Africa , and by obferving thefe Clocks only, he was able to judge much bet¬ ter than the Mailers of the other Yeftels that were in Company, who differed from his Account, fome 8o, fome 100 Leagues, fome more Leagues^ and whereas feveral of them thought themfelves near to Barbadoes , he judged by his Clocks that he was not far from Fuego , one of the Illands of Cape Verde , and the next Day by Noon reached that Eland. But yet this was not fo exa<ft as was expecled ; however, it performed fomewhat to¬ wards this Effedl of finding Longitudes fomewhat more than ordinary, and enough at leaft to give inquifitive Men Occalion to fpeculate, and make farther Trial. And though there hath been no very confiderable Improvement of that Inftrument, or Experiment fince that Time by any, and tho5 I fear it may at beft be infufficient to perform what is neceffary to this Matter, yet I queftion not but that there may be fome other Way that
B 3 may
/
5 rDr. Kook's Experiment
may perform it to a much greater Degree of Per¬ fection, as 1 fhail hereafter endeavour to prove.
2)r. Hoo k’j Experiment of weighing Air* Shewed to the Royal Society, ^Eec . 3, 1662.
r~|p wo fmall Glafs Balls, blown and fealedwith
1 a Lamp, each of them about an Inch and half over, were fufpended at the End of a Beam,
„ and counterpoifed with a fmall leaden Weight 3 and then a Grain being taken away from the Coun- terpoife, fo that the Balls preponderated by a Grain, the Beam was hung into the Globe, and the Mouth of it clos’d, and the Forcer was wrought 3 whereupon, as the Air was condenfed in the Globe, the Balls by Degrees grew lighter and lighter, and the oppofite Counterpoise at length did more preponderate the Globes, than they had before the Condenfation 3 but upon the letting out of the imprifon’d Air, the Balls again recovered their Prepollency, and remained as they were when firft put in.
T H e Experiment affords us a manifeft Froof of the Weight and Spring of the Air, and after what Manner they work upon the Bodies inclofed in it. ift. That though the Air be a heavy Body, yet it not only prefles downwards, as feme have erro- neoufly thought, and fo have imagin’d it fhould break People’s Necks, and roul and preft down the Grafs, and all kinds of weak Plants,as Deufingius fuppofes 3 or fhould prefs a Dilh of Butter, or feme fuch foft Body, quite flat, as Mr. Hobbs imagines. But cT/y, it prefles upwards and Tideways, as much as downwards 3 whence every Body, fufpended in it, does buffer, from this ambient Fluid, a greateT
Prefiure
of weighing Air, 7
Freffure againft its under Side to thruft it upwards, than againft its upper Side, to force it downwards y and does in all Things of Staticks adi according to the fame Laws, and after the fame Manner, that other heavy fluid Bodies work upon the Body they incompafs. And this Experiment, in lliort, is nothing elfe but a Variation of Archimedes's Ex¬ periment of examining compounded Metals, For the two Bodies that weigh againft each other, be¬ ing of a very differing Bulk, though pretty near of the fame Gravity when in the Air, when they are incompafs’d with a more denfe and heavy Fluid, that which is more bulky muft neceffarily lofe more of its W eight or Power downwards than the other, fince it is a known Law of the Staticks, that a Body, remov’d out of a lighter into a heavier Me¬ dium, lofes fo much of its former Gravitation, as the Weight of a Part of the heavier Fluid, equal in Bulk to the inclofed Body, amounts to.
The Ufes that may be made of this Experi¬ ment may, be many, and thofe, I think, not the leaft confiderable.
Fir ft I t may ferve as an Inftance, to fhew by what Means the Vapours and Exhalations are raffed up into the higher Parts of the Air , for if by any Means the Vapours, or Waters rarify’d, obtain a greater Rarity, and confequently a leffer Gravita¬ tion than the ambient Air ; the Preffurc of that muft neceffarily buoy and carry them up fo far, till the Abatement of Preffure on the Parts of the ambient Air, by reafon of their fublime Stations in the upper Regions, and till the Abatement of Heat, that kept the Vapours rarify’d, has reduc’d both to an ^Equilibrium, where they areftay’d and fufpended; which affords us a fecond Ufe, name¬ ly, to explain how the Clouds or Exhalations are fufpended and carried to and fro diredlly at fuch a Height, and no lower nor higher. For fince
B 4 ' it
8 T)r% Hook’j Exp eriment , Sec.
it is found by Experiments made by Torricelli it'} that feveral others, whom I now forbear to name, and the PrefTure of the Air at the Top of Moun¬ tains is differing from what it is in the Valleys,there- fore the Rings of PrelTure (if I may fo call thofe Parts of the incumbent prefling Atmofphere) feem not at all to be regulated by the Form of the Earth’s Surface, that is, are not at all parallel to the Surface of the Earth, but they feem to be regulated rather by the Diftance of the Parts of the Air from the Center of the Earth, or rather are parallel to the Surface (if there be any) of the Air, or to the Superficies of the Sea. And, indeed, I have ve- ay often obferved, not without Wonder, that in cloudy Weather all the under Surfaces of the Clouds have been exactly terminated with a Sphe¬ rical Concave Surface, no one being raifed above or deprefs’d below fuch a determinate Surface. And I have after obferved the Vapours often rife like Smoak upward, till they come to fuch a Height, and then to ceafe afeending, and fpread themfelves in Breadth almoft like Oil upon the Water : The Reafon of all which is, probably, nothing elfe but that at fuch a Height the Air is reduc’d by the Decreafe of PrefTure to fuch a Degree of Ra¬ rity, that it is unable to raife the Vapours any higher, and below it is able to raife them. The Rea- fons how the Vapours come to retain that Degree of Rarity, Sc. is an Enquiry more proper for an¬ other Place.
Thirdly , This may hint us a Solution of a late Obfervation made by an excellent Perfon, and a Member of this Society, that in Fogs with an Eafterly Wind, the PrefTure of the Atmofphere was obferved to be very great. The Reafon of which Phenomenon might, perhaps, be this, that the Cold and PrefTure of the Air being then very great, the Denfity and Gravity of it might there-
Experiments about Glafs Balls. 9
by become fo confiderable, as to raife up many Bodies, even in the Form of Water, and keep them fufpended fomewhat above the Surface of the Earth, though by reafon of the Want of Heat to rarify thofe fmall Parts into aerial Va«* pours, it were not able to carry them to any con¬ fiderable Height.
A Brief Account of the Experiments tried before the Royal Society, with Glafs Ballsy November 19. 1662. Of dri¬ ving out the Air by bare Heat. 2. Of driving it out by Vapours of Water and Spirit of Wine . 3 . Of their breaking of
them fe Ives. 4. Of their breaking by a Knock. 5. Of the Quantity of Water they admitted. 6. Of the fV eight of Air they admitted. 7. Of the Jhrinking and fir etching of them. 8 . Of their breaking outward .
As m a l l Pipe of white Glafs , melt¬ ed over a Lamp, is blown into a pretty large Bubble, the fmall Neck or Pipe of which being, whilft the Ball is yet red-hot, fuddenly and carefully fealed up, I obferved that thofe Bubbles being left to cool, fome of them that were either not very equally or over thin blown, would, in the cooling, break inward, with a very brisk and loud Noife, fome fooner whilft yet hot, others later when even quite cold 3 but this latter yield* ed the loudeft Report. Some, that were ftrong and even blown, remained intire when quite cold : The Balls of which I obferved to endure a much greater and more violent Blow, before they would
break.
io Experiments about Ghfs Balls.
break , than others much of the fame Make, which were left to cool without fealing up. But, when by a pretty brisk Blow they were broken, they yielded, befides the Noife of the broken Pieces, foinetimes a fmart, fome times a more faint Noife. Some of thefe Bubbles whilft thus her¬ metically feafd, being pois'd in a pair of exadt Scales, and then the little feafd End nipp'd off, a S'ibilus or hilling Noife might very fenfibly be heard fora fmall Spaceof about a Second ; after which the fame Scales and Counterpoife being left free, the Bubbles were always obferved to preponderate, fome a ^ of a Grain, others f, others more. The End of fome other of thefe being broken off un¬ der the Water, the Water was obferved to af- cend with a very great Impetuofity, and to look white, until fuch Time as it had fill’d the Bubble or Ball, about -*■ or £ of the whole , fome more, fame lefs, according as they were more or lefs hot when feafd up. Then holding the Bubble over the Flame of a Candle, till the Water was boil'd or exhal'd away, I immediately feafd up the fmall End again, and obferved fome of them to break with a much louder Crack than thofe that had been fealed up when red-hot. Breaking others under Water, I found a much greater Quantity of Water to enter, infomuch as to fill almofi: the whole Ball, leaving a very little Bubble of Air at the Top : Others, that I weighed, 1 found to in~ ereafe fomewhat more in Weight, by the Admiffi- on of the Air, than they had done before by the other fealing. After this, having emptied out the Water, I put into feveral of them a fmall Quan¬ tity of indifferently well rectify 'd Spirit of Wine, and taking the fmall Stem in my Fiand, I held the Ball over the Flame of the Lamp, till the Spirit with great Impetuofity was evaporated, and driven put through the fmall Neck, in at Kind of mifty
Steam ;
II
Experiments about Glafs Balls,
Steam; which ceafing, I immediately feafd up the Neck, and letting the Bubbles cool, 1 found them to be much of the fame Kind with thofe that I had feafd up with Water, both as to the Noife they yielded when broke, and to the admit¬ ting of Water, and for the weighing of Air; only in this thefe two laft Ways differ’d from the firft, that whereas the red-hot Glaffes when cold were clear, thefe, though they appeared clear when hot, were, notwithftanding, all tarnifhed over, with a Kind of Dew in the Infides when cold ; which Dew would quickly difappear, if they were again heated pretty hot. There were feveral other Gircumftances, which, becaufe they will be more notable in other Experiments, I here omit.
The Reafons of which Phenomena 1 humbly conceive to be thefe. Firft , That the elaftical Power of the exceedingly heated Parts of the Air, that are within the Glafs when red-hot, being ve¬ ry much intended, a very fmall Parcel is able to prefs and keep out all the reft of the ambient, con¬ tending Atmofphere ; and whilft it has that Abili¬ ty, the Paffage being fhut, the ambient Air is him der’d from rufhing in that Way, though the Air Within growing colder, and fo lofmg its Elater, could not have been able to have hindered it. * Now the Prefliire of the included Air againft the Sides decreafing with its Elater, and that with the Heat, and the Prefliire of the ambient, re¬ maining the fame, that curious arched Vault of the Glafs is forcibly prefs’d and crufh’d together, and fo the Particles are put into a clofer Texture. And that they are fo, I found by this Experiment. I fitted a pretty large Bubble with a fender Neck into a Bolt-Head, whofe Neck was drawn very
* Query, Whether the Bubbles jhr'mk ?
fmall
l x Experiments about Gkifs Balls.
fmali, and left only big enough to contain the Neck of the Bubble., and whofe Bottom was cut off, that thereby I might include the Ball. Ha¬ ving fo fitted the Ball and Bolt-Head, 1 fhut up the Bottom again with Cement, and filling up the Space left in the Bolt-Head with Water, till it reach’d into the Small of the Neck, Inipp’d off the feal’d Top of the Bubble, whereupon the Water in the fmall Neck rofe about a Barley Corn’s Breadth, which could proceed from nothing elfe than its Return to its former Dimenfions, before it was fealed up j which affords us a noble Inftance of Compreflion, where that fo hard and well com- padledBody of Glafs is comprefs’d into lefler Room, and that by no greater a Force than that of the Pref- fure of the Air 5 whence we may conclude that the Parts of that Body are not fo clofe joined together, but that there may be Pores or Recedes left be¬ tween them, into which they may be protruded, and fo be made to lie clofer to each other, which whether Water and other fluid Bodies may not do the like, Trial will inform.
The Experiments fugged: thefe Queries.
What may be the Caufe of Noife or Sound ?
B y what Means Heat rarifies and expands Bo¬ dies, and Cold condenfes ?
Whet h e r the Caufes of the almod fimilar Phenomena of the Glafs Drops, may not be de¬ duced from thefe Principles : Or what may be their Caufes ?
The Strength of a Knock, or what may be the Force of falling Bodies ?
W h at is the true Weight of Air in Winter ?
Wuethe r Bodies, that will not melt, may be expanded by Heat ?
T h e Difference of the external and internal Preffure increafmg by the Decreafe of the included Air’s Elater, if feme Parts of this Arch (if 1 may
2- fo
Experiments about Glafs Balls. 13
fo call it) be weaker or irregular, the ambient Preflure breaks it in : Even as in Architedlure the fame would happen in thofe larger Arches, if in either of thefe Particulars they deviated from the Rules of that Art. But if fufficiently ftrong and equal, the ambient Preflure makes, the chryftalline Vault the firmer, as in Arches of Stone is com¬ monly obferved. The Caufe of the Noife I dare not yet determine, but I think it worth a further Enquiry, whether it proceed not from the Impetus wherewith the broken Pieces of Glafs are dallied againft one another, though the Noife feem of another Kind ; or from the fudden milling of all the Parts of the ambient Air towards the Middle of the Ball, whereby all the other Parts of the circumambient being likewife moved towards the fame Middle, the Drum of the Ear may likewife be moved, and fo a Sound heard : Or 3 i/y. Which I think the moft plaufible, from the fudden and violent rufhing towards the Center, and (by there meeting each other, or at leaft the broken Particles of Glafs) there finding as fudden and vio¬ lent a Recoil or Repulfe, one of which two laft (if not a third, namely ,the fudden flying out of the Air) feems to be the Reafon of the Noife of a difeharged Shot of Powder. The Alteration, as to Weight, does clearly enough proceed from the Admiffion (which the Hilling plainly enough fpeaks) of the heavy Particles of Air. A manifeh Experiment that Air does gravitate in Air. The violent rufh- ing in of the W ater argues the forceable Preflure of the external, as the Multitude of Bubbles do the languid Refiftance of the included Air.
( 14 )
An Account of fome Trials for the finding how much , afc ending and de fie ending Bo¬ dies prefs upon the Medium through which they pafs : Made before the Royal Society, cDec . 24. and cDec . 31. 1662,.
AGlafs Tube about fourteen Inches long, and an Inch and half over, being open above, but fliut beneath, was hung by a Piece of Tape faftened about the End of it, to the End of a Beam then being fill’d with Water, and a
round Glafs Bali fomewhat more than an Inch in Diameter (which was made heavier than Water, by Quickfilver included in it) being hung by a
String
The Trejfure of Bodies , See. 1$
String of Silk fo far within the Tube, that it was quite covered with Water. The other End of this String was tied to a Wire, that was faftened to the End of the Tube. This Tube, I fay, thus accoutred, being hung at the End of an exact Beam, was counterpois’d with fomewhat more than 3 6 Ounces Troy. Then the Scales being in a very exaeft Equilibrium, the Silk String, by which the Ball hung, was fuddenly cut afunder with a fharp Pair of Sciffers. And the Beam, all the while the Ball was defeending through the Water, and after it came to the Bottom, kept its former horizontal Parallelifm. This was repeated a fe- cond Time with the like SuCcefs.
At the fame Time in the fame Tube, as it hung in this Pofture, there was let down to the Bottom of it a fmall Piece of Lead, which had a fmall Loop of Wire, through which a Silk String being put, a round Glafs Ball much lighter than W ater, and about the former’s Bignefs, was, by that String, drawn down, and kept at the Bottom of the Water, and the other End of the String was faftened about the former Wire. This done, the Scales were brought to an Equilibrium, and then, as before, the Thread was cut, and the Ball quickly afeended to the Top ; in which Time the Beam was obferv’d to be very much turned from its Equilibrium, and upon Trial fix Grains, de¬ tracted from the Counterpoife, was requifite to bring them to an Equilibrium. This laft Experi¬ ment was twice repeated, but in the latter Trial the Parallelifm of the Scales was not at all difturb’d, as in the former Experiment; which gave Occa- fion for a Conjecture, that the former odd Pheno¬ menon was caufed by feme extraordinary Acci¬ dent.
In Profecution of this Enquiry, Lee. 31. Tri¬ al was made by a Variation of the former Expe¬ riment
1 6 4 The cPreffure of Bodies
riment; for the Thread of Silk that the Ball hung by5 was not tied to the former Wire, but to a Suftentaculum above the Beam , then the Scales being brought to an Equilibrium, and the String cut as before, the defcending Ball made that End of the Beam, to which the Tube hung, to be ex¬ ceedingly deprefs’d, and being come to the Bottom it kept the Beam in that Pofture.
Further, that it might be known how much heavier that End was than the other, whilft the Ball lay at the Bottom, the Beam was brought to an Equilibrium ; after which, fix Grains were taken from the Counterpoife of Weights. Then the Ball being tied by a String as before, and the Scale wherein the Weights hung being kept up to a convenient Height, that the Beam might hang- parallel to the Horizon, and the String cut as be¬ fore, the defcending Ball was obferved manifeftly to deprefs the Tube End. Trial was made a third Time by counterpoifing and ordering all Things, as in this fecond Trial, and detradling only three Grains, notwithfiianding which, the defcending Ball manifeftly deprefs’d the Tube End j which lalf Trials were a Confirmation of the firft Experiment, when the Ball was hung to the Wire.
These Experiments feem to hint this Axiom, That every Body, whether afcending or defcend¬ ing in a fluid Body, does add fo much Weight or Prefliire to that fluid Body, as its own W eight a- mounts to, and not as much as the Weight of fo much of the Fluid as is equal in Bulk to what the moved Bodies amounts to.
T h i s I fhould have put as an Axiom, did not fome Difficulties fufpend my Aflent.
Firfi , Since the fwifter a Body is moved, the greater Refiftance it finds from the Medium through which it pafles, and confequently the ftronger is its Prefliire againft that Fluid 5 and fince
defeend*
/
on different Mediums. 17
defcending Bodies grow fwifter in their Motion, the lower they defcend, it feems rational to judge, that the defcending Ball’s PreBure, on the Water, fhould be increafed with its Swiftnefs.
Next, fince the Body that hinders its Moti¬ on is a Fluid, it feems fomewhat difficult to con¬ ceive, how the PreBure of a defcending Body can be communicated to the Bottom, fince the Parts of the Fluid are circulated. And no lefs difficult is it to fay, on what Part of the Bottom the PreBure refts 3 whether on the whole, or on¬ ly that Part immediately fubjacent to the falling Ball j for which Way foever is taken, there are feveral Difficulties fomewhat hard to be explica¬ ted.
^thirdly , I f the Weight of the defcending Bo¬ dy be all the while fuftained by the Fluid, and confequently by the Bottom, how comes the Bo¬ dy, when it touches the Bottom, to prefs with more Force than its own Weight - as is evident, in Bodies defcending through the Air.
Fourthly , Since the PrefTure of a fluid Body, againft the Bottom, is greater, or lefs, according to the Height of the Surface of the Fluid above it : It feems that an afcending Body, in Water, does manifeftly contradid: this Axiom.
Corollaries, deducible from thefe Expe¬ riments, certainly made, may be fuch as thefe :
Firft^ That Exhalations and Vapours prefs not lefs upon the Surface of the Terraqueous Globe, when they afcend, than w hen they are fall¬ ing ; nay, than wffien they are fallen : The Certain¬ ty of which, I think, were worth examining.
Next, That the PreBure of any contained fluid Body, againft the Sides of the VeBel, will be abated by opening an Hole at the Bottom ; though the Height of the Water be continued the fame. That is, that the PreBure of a Perpendicular
Vol, I. C Height
1 8 2)r. H o o vJs 'Enquiries for Greenland*
Height of running Water, is not the fame with that of Handing Water.
Thirdly i I t ihould feem, that the FrefTure of a River, againft the Pillars of a Bridge, is lefs whilft the Water is running between them, than when that Paifage is Hopp'd, though the Height in both remaineth the fame.
2)r. H o o k 9s Enquiries for Greenland.
Jan . 14 i66t.
What, and how much, was the Heat of the Sun in the midil of Summer, compared with the Heat of it in England ?
W h a t is the mofl Conflant Weather there, whether clear, cloudy, rainy, mifly, foggy, &c ? Or what moH ufual at fuch and fuch Times of the Year ? Next, what ConHancy or UnconHancy there is of the Winds to this or that Quarter of the Horizon, or this or that Part of the Year? What the Temperature of each particular Wind is ob« ferved to be j and particularly, whether the North be the coldeH, if not, what Wind is ? What Wind is ob ferved to bring moH Ice, and what to make a clear Water at Sea ? What Currents there are, how fail, and which Way they fet ? Whether thofe Currents are not Hronger at one Time of the Moon than another, whether always running on6 Way ? What is obfervable about the Tides, Spring or Neap ? Whether the Sea Ice be fait or freih ? What Rivers there are in the Summer ? What Fowl are found to live there, and what BeaHs , how they are imagined to fubfiH in the Winter j how they breed and feed their young ? What Ve¬ getables grow there, and whether they yield any Fruits ? How deep the Cold penetrates into the Earth ? Whether there be any Wells, or deep Pits, or Mines, wherein the Water will remain
unfrozen
2)r. Hoo k *s Enquiries for Iceland. 19
unfrozen at the Bottom ? How the Land trends ? And whether the Parts, under or near the Pole, be there thought to be Sea or Land ? Whether the Perfon made any Experiment, about the Load- ftone or magnetical Needle, or any mathematical Obfervations, about the Height of the Sun and Lu¬ minaries, or their apparent Diameters, or Refracti¬ on, or the like ?
What Fifti moil frequent thofe Seas, and any thing about their fifhing, with the ufual Bignefs of Whales, &c. their Strength, the Anatomy of their Entrails ? Whether any People do or have been known to ftay there all the Winter, and how they do or have Ihifted ? How near any has been known to approach the Pole ? What Notice he has taken of the Moon,
< Dr . Hook’j Enquiries for Iceland.
Jan • 2i. 1 66 j,
Ho w deep the Ground is frozen ?
What Wind is coldeft ?
What Rivers and Springs they have ?
The Anatomy of Whales, or other Very large Fifties.
About the Lungs of Whales and Contrivance of Refpiration in other Fifties and Morfes ?
Concerning the Fountain that is hot e~ nough to fcald a Fowl.
W hether the burning extraordinarily of He cl a portend foul Weather ?
Re fraction, 'whether the feven Stars are feen in the Pleiades ? Whether Mercury can be oftener feen than in England ? The differing Heat of Summer and Winter : How near the Moon may be feen to the Sun ?
A n exaCfc Obfervation of the Eclipfes that happen,
C 2 The
2,0 23r. Hoo ids Enquiries for Iceland.
4
The Saltnefs of the Sea-water, by boiling, how much Salt it yields ?
The Height of the Quickfilver in the Torricel Experiment.
What Wind blows moft and ofteneft ?
The ufual Temperature of the feveral Winds there.
About Corruption and Prefervation of Bo¬ dies.
What Bodies will keep in the Snow, what not ?
The burning of the Mountain, other Obfer- vations with the Needle in feveral Plates about Hecla , or the other fiery Mountains, and in other Places of that Ifle.
The Figure of Snow, whether Hexangular, whether always larger than in thefe Parts ?
The ufual Bignefs of Hail-Stones and Figure.
What is obfervable about Meteors, as Ignis Fat nits , Star-fhooting, Thunder, and Lightning.
What Kind of Subftances are caft out of the burning Mountain.
About Haloes and Rainbows, any thing ex¬ traordinary.
W h a t kind of Ores, Stones, Clays, Mine rals, &c. it yields.
W h e t h e r there be any of the Selenitis , o Mufcovy Glafs to be found there.
The Declination, Inclination, and Variatio of the Magnet in feveral Parts of the Ifle, wit the Diflances and Latitudes of thofe Places, ; near as may be.
W hether the fame Point of a Magnet, th; is a Pole of that Stone here in England , will t fo there.
Whether the fame Part of a F trrella , tha put upon Quickfilver, will lie toward the Ear here in England , will do fo there likewife.
Wh
2 I
Tjt. Hoo k \r Enquiries for Iceland*
Whether the attractive Virtue of the Mag¬ net increafe or diminifh there, in refpeCt of what it is found here.
W high Pole is there ftrongeft.
Whether Iron be more or lefs apt to ruft there than here.
What living Creatures, tame and wild, live and thrive there.
Any thing of that Kind ftrange or remarkable among the Beafts, Birds, InfeCts, or Fifties , as about their Generation, living in the Winter ; for what they are or may be made ferviceable ; either for Burthen, Swiftnefs, Furrs, Feathers, Meat, &c.
What Kind of Vegetables thrive beft in that Ifland, as Trees, Shrubs, or Plants, and what Kind of Grounds they thrive beft in , what Kinds of Vegetables the Sea yields, differing from our Englijh. In what their Husbandry differs from, ours, and whatfoever of that Kind is remarkable.
What Woods it yields good for Building, Shipping, or other neceftary TJfes.
What notable Virtues are attributed to this or t’other Plant , whether for Divination, Phy- fick, Dying, Smell or Tafte, &c.
The Seeds of as many as may be gotten toge* ther, with their Names.
How feveral Creatures fubfift in the Winter.
What are the predominant Colours of Ani¬ mals. ' . 5
What general Change Is made on the Ship- men, that does not feem immediately to proceed from Cold, as what Difeafes they are moft fubjedt to.
The Nature, Difpofition, Manners, and Cu** floras of the Natives.
C 3.
Their
xx *Dr. H o o k \r Enquiries for Iceland*
T heir Apparel for Warmth, Houfing, Vi¬ ctuals, Firing, Bedding, Cookery, and other Ob- fervables, either ACtions or Utenlils, &c.
Any notable Effefts produced by Cold,
The Height of the Iflands of Ice, their Depth * whether it be frefh Water ; whether it feem to be made up of Snow, and feem to lie in Plates one above another.
Whether Spirits appear ; in what Shapes ^ what they fay or do ; any thing of that Kind ve¬ ry remarkable and of good Credit.
How much the Celeftial Bodies are elevated by Refraction above their true Place.
What Currents there are, the T ime of the Tides in feveral Ports 5 their great riling and fall¬ ing in feveral Places , any thing notable concern¬ ing them.
What Condition the Body is in that is pre- ferved by Snow, whether fhrunk or fwelPd, or chang’d in Colour or Talte, &v.
Whether Quickfilver will congeal.
A bladder full of Englijh Air carried thi¬ ther, and one of that Bland Air brought back.
( *3 )
2)r. Hoc k V Trofofials , finding out the
Refinance of the Air , to Bodies mov'd through it.
Tryal fhould be made with Pendulums of all Sorts, whofe Weights fhould be made of feveral Sorts of Materials , as of Metal, Stone, Wood, Feathers, Wool, &c. and thofe falhioned into feveral Shapes, as round, elliptical, fquare, oblong, flat, to move flat-ways and edge-ways, and the like ^ then to have one common Standard, or Pendulum, by which the Celerity and Durati¬ on of all the other are to be meafured.
Tryals fhould be made with feveral of thefe Pendulums, in the exhaufled P^eceiver, where there is a much lefs Quantity of Air , and like- wife in the Receiver, where the Air is very much condenfed 3 and the Differences meafured, as be¬ fore, and recorded, then compar’d with one an¬ other, and then with thofe in the free Air.
Tryals fhould be made with Bodies of feve¬ ral Sub fiances, and each of thofe of feveral Shapes, which fhould be let fall from feveral Heights ; and the Times of each of their Defcents to be exa&ly meafured by a Pendulum, and recorded.
Tryal likewife fhould be made by fhooting. Horizontally, feveral Kinds of Bodies, with a Crofs-Bow, or the like, from the Top of feme high Place, and fo obferving the Time before they touch the Ground. And the
Tryals fhould be made by fhooting Bodies perpendicularly upwards, and fo obferving both the Time of their Afcent and Defcent.
Tryals likewife fhould be made by fhooting Bullets, or other Bodies, Horizontally • and fo to obferve with what Force they hit a Body, ac¬ cording as the Body is nearer, or further, from
C 4 the
^4 Experiment about the Refraction
the Inftrument that fhoots. And thefe Tryals to be made with Inftruments of feveral Strengths.
2)r. Hoo r 9s Experiment before the Royal Society, February n. 1 66 f about the Refraction of Ice and Cryftal.
a v i n g obferved it to be alrnoft a general
J[ I Rule in Nature, that of pellucid Bodies, thofe are found to have greateft Refraction to¬ wards the Perpendicular, which are mod mafly and heavy in Bulk, I chofe a very pure and pel¬ lucid Fragment of Ice, about an Inch thick, which had very few, if any, perceptible Blebbs or Bubbles in it. Then I took a large cylindrical Cryftal-Glafs, about fix Inches over ; and filling It with very fair Water, I put into it this clear Piece of Ice, which did manifeftly fwim, with fe¬ veral of its Parts, above the Water , and though I feveral Times deprefs’d it with my Finger, yet would it incontinently rife, as foon as 1 had re¬ mov’d my Finger. Then I took it out, and with a very fharp edg’d Knife, I fhaved one End of it, (which is very eafy to do) into the Form of a ve¬ ry blunt Wedge, fo that the two Sides of the Edge compos’d an Angle of about ninety Degrees j then fmoothing thofe fhaved Sides, by rubbing them a little with the Palm of my Fland, I put it into the Water with the Edge downwards, and holding it pretty near that Side of the Glafs, which was next my Eye, I cou’d plainly perceive, by looking through that Edge, that an Objedt, placed againft the oppofite Side, was manifeftly refradted. For faftening a fmall Piece of Lead, fo that the lower End of it reach’d about an Inch under Water, I could very plainly fee that lower End, a little be¬
low
of Ice and Cryftal.
low the Bottom, when, looking through the Ice, the Bottom of it appear’d above the Edge of the Ice ; that is, I faw the fame Objedl in two Places, Now becaufe the Refradlion of the Ice made it appear higher than really it was, it {hews that the Refradlion in the Ice was lefsthan Water 3 which will more plainly appear by the Figure : Where Ji I K L reprefents the cylindrical Glafs, that
held the Water m e, a Piece of Lead hung a- gainft the Side of the Glafs , a b c, the blunt Edge of the Piece of Ice • D, the Eye ; n 0 p, the Surface of the Water 5 f e, the refradled Line, in which the Point e appeared to the Eye , g c, the u lire fra died. This I feveral Times have re¬ peated, and always found the fame.
The Ufe of this Experiment may be, 1/, For to make an Exception from that general Rule of M. Des Cartes , in the ninth Sedlion of the fecond G hap ter of his Diopticks , where he fays, Quanto firmiores & folidiores exigucs partes corporis alien - jus pellucidi flint , tanto facilius liimini tranfituni permittunt . For, it feems, by this Experiment, not to be the greater or lefs Fluidity, or Firmnefs of Body, that caufes a Difference in Refradlion, but a more ratify ’d or condens’d Texture.
Next j
±6 Method of making Experiments.
Next, I t affords us two Arguments againft their Opinion, who affirm Cryftal to be generated of Ice. For, Firft, As to its Weight, this is found to fwim upon Water ; whereas the other links. Next, 1 he RefraClion of Cryftal is ob- ferv*d to be greater than that of Glafs 3 whereas this of Ice I find to be lefs than Water.
Thirdly , This lefs Refraction of Ice, I take to be a good Argument, that the Lightnefs of Ice, which caufes it to be born up of the Water, is not caufed only by fmall Blebbs or Bubbles, but from the uniform Conftitution, or general Tex¬ ture, of the whole Mafs*
2)r. H o o k \r Method of making Experi¬ ments.
rri ji e Reafon of making Experiments is, for | the Difcovery of the Method of Nature, in Its Progrefs and Operations.
Whosoever therefore doth rightly make Experiments, doth defign to enquire into fome of thefe Operations ^ and, in order thereunto, doth conftder what Circumftances and EffeCls, in that Experiment, will be material and inftru&ive in that Enquiry, whether for the confirming or de- ftroying of any preconceived Notion, or for the Limitation and Bounding thereof, either to this or that Part of the Hypothefis, by allowing a greater Latitude and Extent to one Part, and by diminifhing or reftraining another Part within nar¬ rower Bounds than were at firft imagin’d, or hy¬ pothetically fuppofed.
The Method therefore of lfiaking Experiments by the Royal Society, I conceive, fhould be thiSo
Firft ,
Method of making Experiments . 2,7
Firfi , To propound the Defign and Aim of the Curator in his prefent Enquiry.
Secondly , T o make the Experiment, or Expe¬ riments, leifurely, and with Care and ExaCinefs.
^thirdly , T o be diligent, accurate, and cu¬ rious, in taking Notice of, and (hewing to the Aftembly of Spe&ators, fuch Circumftances and EffeCts therein occurring, as are material, or at lead, as he conceives fuch, in order to his The-
j t
cry.
Fourthly , After finifhing the Experiment, to difcourfe, argue, defend, and further ex¬ plain, fuch Circumftances and Effetfts in the pre¬ ceding Experiments, as may feem dubious or difficult : And to propound what new Difficulties and Queries do occur, that require other Trials and Experiments to be made, in order to their clearing and anfwering : And farther, to raife fuch Axioms and Proportions, as are thereby plainly demonftrated and proved.
Fifthly , T o regifter the whole Procefs of the Propofal, Defign, Experiment, Succefs, or Fail¬ ure ; the Objections and Objectors, the Explana¬ tion and Explainers, the Propofals and Propoun¬ ders of new and farther Trials j the Theories and Axioms, and their Authors 5 and, in a Word, the Hiftory of every Thing and Perfon, that is material and circumftantial in the whole Enter¬ tainment of the faid Society $ which (hall be pre¬ pared and made ready, fairly written in a bound Book, to be read at the Beginning of the Sitting of the faid Society : The next Day of their Meeting, then to be read over, and further difcourfed, aug¬ mented or diminifhed, as the Matter fhall require, and then to be fign’d by a certain Number of the perfons prefent, who have been prefent, and Wit- nefles of all the faid Proceedings, who, by Sub- 1 fcribing
2*8 Mr* Oldenburg h V Letter , &c.
bribing their Names, will prove undoubted TeftL niony to Pollerity of the whole Biftory,
Oldenburg hs Letter to Dr.
Hook, Aug.\r 3. 1665. Concerning the \ 'Plague then . and Grafs in Sheef s and Oxen's Lungs .
\ " . t . V/ ,
s i r, ■ ;
I cannot but commend you for being £o careful of yourfelf in this dangerous Time, as not to venture to come amongft us, efpecially when you find yourfelf any ways out of Temper, The Sicknefs grows ftill hotter here , though I find by all my own, and other Men3s Obfervati- qnsa that very few of thofe Houfes whofe Inha¬ bitants live orderly and comfortably, and have by Nature healthy Conftitutions, (you muft take all thefe together) are infedled , and I can fay, (God be praifed for it ) that as yet not one of my Ac¬ quaintance, except an under Poft-Mafter, who lived clofely and naftily, and had all Sorts of Peo¬ ple coming to his Houfe with Letters, is dead : So that, generally, they are Bodies corrupted, and Perfons wanting Neceffaries and comfortable Relief, that fuffer moft by this Contagion.
That Obfervation, you mention of Mr. Boyle"' s, is this, that one of thofe two Phyficians, Dr. Clerk , and Dr, Lowery had allured him, that he had feveral Times found, in the Lungs of Sheep, a confiderable Quantity of Grafs, in the very Branches of the A [per a Arteria $ and the other had related to him, that a few Weeks fince, he, and a couple of Phyficians more, were invited to look upon an Ox, that had, for two or three Days,
a almoffc
Account of an Earthquake at Ballalbre.
almoft continually held his Neck ftraighfc up, and was dead of a Difeafe, the Owner could not ton- jedure at , whereupon the Parts belonging to the Neck and Throat being opened, they found, to their Wonder, the Afpera Arteria , in its very Trunk, all fluffed with Grafs, as if it had been thruft there by main Force ^ which gives a juft Caufe of marvelling and enquiring, both how fuch a Quantity of Grafs fhould get in there, and how being there, fuch an Animal could live with it fo long.
Extract of a Letter from Ballalbre, Jan. 6*
1 661. From Mr , Henry Powell, t§ his Father Air. William Daniel!, upon London-Bridge : Giving an Account of an Earthquake , &c. after the Appear* ance of the Comet then .
Th e fame Star appeared in our Horizon, a* bout the fame Time 5twas feen with yon ; The Effeds, in Part, have already been here, by unfeafonable Weather,, great Mortalities amongft the Natives, Englijh , and others. We have had feveral Earthquakes unufual here, which, with hi¬ deous Noifes, have, in feveral Places, fw allowed up Houfes and Towns j but about feven Days Jour¬ ney from Dacca , where were at that Time three or four Dutch , they, and the Natives, relate this Story. That in that Place the Earth trembled a» bout 32 Days and Nights, without Intermilfion ; at the latter End, in the Market-Place, the Ground turn'd round as Duft in a Whirl-wind, and fo continued feveral Days and Nights, and fwallow¬ ed up feveral Men, who were Spedators, who funk and turn’d round with the Earth, as in a
Quagmire *
30 Account of an Earthquake at Balia fore.
Quagmire $ at laft the Earth worked up, and caft up a great Fifh, bigger than hath been feen in this Country, which the People caught ; but the Conclufion of all was, that the Earth funk with 300 Houfes, and all the Men, where now appears a large Lake, fome Fathoms deep : About a Mile from this Town was a great Lake full of Fifh, which, in thefe 32 Days of the Earthquake, caft up all her Fifh on dry Land, where might have been gathered many, which had run out of the Water upon dry Land, and there died ; but when the other great Lake appeared, this former dried up, and is now firm Land.
Extract of another Letter from the fame Mr • Powell, to the Terfon abovementi - onedy from CafTumb, Seft. 27. 1666.
Mine, laft Year, advifed of the unknown Earthquakes which affii&ed moft of thefe Parts, in fome to the deftroying of whole Towns, viz. June ift, in Agra, the King’s Seat, at three in the Afternoon, fuch a Darknefs poffefs’d the Country, that none could fee his Fellow' in the Streets, nor his Hand, though never fo near his Eyes, which continued half an Hour, and then diifolved in Rain. It has pleas’d God to fend this Year fuch Rains and Overflowings of the Pvivers, that in many Places whole Towns, with Cattle and Men, have been carried away, to the Be- ftruftion of many Thoufands. About the latter End of Auguft , there was fuch a Storm about Pat- lava, that it roll’d, as it were, that great City, their Houfes, in Heaps, deftroyed many People’ and continued three Days and Nights, in which we have loft a Salt-petre Boat of Value, and the
Dutch
Of a petrified Bone , &c. 31
Dutch another ; alfo both ours and the Dutch Houles, in all thofe Parts, are blown down : We expedt the fame, it being ufual with us about the Middle of October yearly, but fuch Inundations and Storms wrere never before heard of.
An Account of a petrified Bone . An oddly- coated Stone Bottle : And a double Goofed Egg, Produced before the Society, by ©r. Brown of Norwich, Feb . 27- 1 66?.
This Bone was found laft Year, 1666, on the Sea-Shore, not far from Winterton in Norfolk .
I t was found near the Cliff, after two great Floods, fome thoufand Loads of Earth being broken down by the Rage of the Sea, as it often happeneth upon this Coaft, where the Cliffs con- lift not of Rock, but of Earth.
That it came not out of the Sea, may be conjedlured, becaufe it was found near the Cliff ; and from the Colour, for, if out of the Sea, it would have been whiter.
Up o n the fame Coaft, but as I take it, nearer Hdsborough , divers great Bones, are faid to have been found ; and I have feen a lower Jaw con¬ taining Teeth of a prodigious Bignefs, and fome- what petrified. All, that are found on this Coaft, have been found after the falling of fonie Cliffs ; j where the outward Cruft is fallen off, it clearly refembleth the Bones of Whales, and great ceta- ceous Animals, comparing it with the Skull and |j and Bones of a W hale, which was caft up on the ll Coaft near Wells , and which 1 have by me.
The Weight thereof is fifty five Pounds.
T h 1 s
I
31 Obfervations of Water
This Bottle was filled with a green Malaga $ above feven Years ago, and fet up in a Ni&rio of a Wine-Cellar-Wall in Norwich , where it con¬ tracted this Mncor : It was full at firft, and is not yet empty.
A G o o s e-E g g, with another in it, or at leaf!: over it ; the outward Egg containing nothing but the White. The like I have obferved in Hen’s and Turky’s Eggs. I would not omit to fend it, be- caufe though it fometiines happeneth, yet few have the Advantage to fee it, efpecially in a Goofe-Egg.
Mr. Charles Towneleybr Relation, with Ob¬ fervations of the late Eruption of Water out of Pendle-Hill, Communicated by Richard Towneley, Efq\
Au g u s t iS. 1669, betwixt 9 and 10 o5 the Clock in the Morning, there iffued, out of the North-Weft Side of P e n die -Hill , a great Quan¬ tity of Water : The Particulars of which Erupti¬ on, as I received them from a Gentleman living hard by, are thefe. The Water continued run¬ ning for about two Hours , it came in that Quan¬ tity, and fo fuddenly, that it made a Breaft of at Yard high, not unlike (as the Gentleman exprefs’d it) to the Eager at Roan in Normandy , or Oufe in Torkjhire 3 it grew unfordable in fo fhort a Space, that two going to Church on Horfeback, the one having paffed the Place where it took its Courfe, the other being a little behind, could not pafs this fudden Torrent. It endanger’d breaking down of a Mill-Dam, came into feveral Houfes in Worfion , (a Village at the Foot of the Hill) fo that feveral things fwam in them. It iffued
ijfuing out of Pendle-Hill 35
out at fomefive or fix feveral Places, one of which was conliderably bigger than the reft, and brought with it nothing elfe but Stone, Gravel, and Earth, He moreover told, that the greateft of thefe fix Places clofed up again, and that the Water was black, like unto that of Mofs-Pits ; and laftly, that fome fifty or fixty Years ago, there happened an Eruption much greater than this, fo that it much endamaged the adjacent Country, and made two Cloughs or Dingles, which, to this Day, are called Oburfi (or, in our Lancafhire Dialed:, BraJT) Cloughs. Thus far this Gentleman related j what follows take from my felf : Going, fince this, to fee what I could of this Accident, I found no- ‘ thing that did contradid: the abovefaid Relation. What I obferved more concerning this and other Eruptions, is, that palling under the North-Eaft End, commonly call’d the Butt End of Pendle , I faw feveral Breaches in the Side thereof, at feve¬ ral Diftances from the Top , from thefe, Stones, mix’d with Earth, had been tumbled down, and lay in fuch a confufed Order, as if they had been brought thither by fuch a like Eruption as this laft , and enquiring of a Country Fellow, who was our Guide, he confirmed the Conjecture, and told us, thefe Breakings out of Water were very frequent, fo that he wonder’d we took fo much Pains to go and fee this late one. I went to look amongft the Rubbifh of Stone and Earth, of one of thefe Breaches, to fee if I could find any thing like Ore, but could find nothing. Having pafs’d the End of the Hill, and coming to the other Side, we, after a fhort Time, difcovered the mentioned fix Breaches, of which two feemed to be very near the Top of the Hill, and in the fame hori¬ zontal Line 3 the others at feveral Diftances from the Top. I went only to the biggeft of thefe Breaches, in which I obferved thefe Particulars : Vol. I. X> The
34 Obfervation of Water , &c.
The Water had taken away the Soil, (which was But about two Foot deep) and bared the Rock, betwixt feme twenty and thirty Yards in Rreadth, and downwards a ccnfiderable deal more : It an- peared evidently, that the Water came from be¬ twixt the Swarth and the Rock, for, at the Top Of the Breach, we faw feveral Holes, whereat the Water had iffued forth, others were clofed up with the Fall of the Earth j wherefoever the Wa¬ ter had taken away fome two Foot deep of Earth, the Rock appeared : Amongft the Rubbifh I found nothing that could be fuppofed to come out of the Bowels of the Hill, but only fuch Stones as might lie loofe on the Rock, amongft the Earth that covered it. This is what I obferved in the Breach, which, for Bignefs, was moft remarka¬ ble, and prefume, I fhould have found nothing worth Notice in the lefter ones. Though the Noife of this Eruption was fo great, that 1 thought it worth my Pains to enquire further into it ; yet,, in all thefe Particulars, I find nothing worthy of Wonder, or what may not be eafily accounted for. The Colour of the Water, its coming down to the Place where it breaks forth, between the Rock and Earth, with that other Particular of its bring¬ ing nothing along but Stones and Earth, are evi¬ dent Signs that it hath not its Origin from the ve¬ ry Bowels of the Mountain, but that it is only Rain-Water, coloured firft in the Mofs-Fits, of which the Top of the Hill (being a great and con- llderable Plain) is full, fhrunk down into fome Receptacle fit to contain it, until at laft, by its Weight, or fome other Caufe, it finds a Paftage to the Side of the Hill, and then a Way betwixt the Rock and Swarth, until it break the latter, and violently rufh out. The great Eruption, men¬ tioned to have happened fo many Years ago, per¬ haps is that taken NqUCQ of by Qamhden in his
Bnttannicc^
/
Account of Earthquakes at Ternata. 35
ft rittannia , pag. 613. Verurn hie mens damno quod fubjetio agro jam pride m intulit maxi mam aqua - mm vim er uhlans , & certijjimo pluvice indicio , quo- ties eius vertex nebula, vefiitur , maxim e in/ignis eft.
I know not whether it may not be worth Notice, that going to the Top of the Hill, and obferving a conflderable Part thereof, efpecially towards the Skirts, where Turfs had been gotten, I found that the Rock reach’d within a Yard or two of the highefb Part ; confldering this, with what I ob- ferved at the mention’d Breach, and feveral other Places, I think it is very probable, that the whole Mountain, as great as it is, is one continued Rock , and it may be a Queftion, Whether all other Hills be fo or no ? But this 1 leave to fur¬ ther Enquiry.
ExtraB of a Letter from the Erefident Cornells Frans, and the Council in Ter¬ nata, to the Heer William Maatluiker, and the Council in Banda, dated the nth of Auguft, 1673. Concerning Earthquakes there ,
We hereby acquaint you with two Wonders, the like not before heard of The firft,
! that on the 2,0th of May, being Saturday Even¬ ing, that great and high Hill Qammaknotra , a~ bout thirteen Miles from hence, is, for the niofb Part, flown up in the Air, which caufed the next 1 Day, being Whit [unday ^ fo great a Darknefs, that we could hardly fee one another 9 and this was accompanied with a great Earthquake, and all the ■ Land, both here, at Man ado , Cbianco , Jafangy , I and Mindanao , a hundred Miles from hence, and I Cod knoweth how much further, was covered
D % with
36 Account of Earthquakes at Tefnata.
with Afhes a Foot thick, and fo much was fallen in the Sea, that a fmall fluit Ship, in going and coming from Man ado , was feveral Times hinder’d in her failing, through the great Quantity of Alhes driving, and fome Houfes and Negeries, at the Foot of the Hill, were quafh’d with the Weight of the Allies fallen on them.
Th e fecond Wonder is, that on the 12 th pre- fent, in the Night, between 11 and 12 o’ the Clock, a hidden Earthquake furprized us, with fuch terrible Shakings, as pofllbly the like was ne¬ ver known, which encreafed fo violently, that the Hill of Ternata , on the South Side, was rent from Top to Bottom j the King’s Mandarfahas Stone-Houfes were caft down j Parts of Hills funk ; all the tiled Coverings, with feveral Walls, call: down , and the Sea was in that Manner di- fturbed, that the Ships, here in the Road, expect¬ ed all to have been caft away , and Quantity of Filh was flung on the Shore, with many other ftrange Paflages. And that which is worfe, the faid Earthquake continueth to this prefent Time ; and here is nothing to be feen but bad Spectacles of Ruin. By a further Letter from the faid Pre- fident of : Ecrnata , of the firft of September , the before-going Relation is confirmed, and that the Earthquake yet continued, fo that the Night be¬ fore, the Houfes were thereby terribly fhaked ; all which is more at large exprefs’d in a Relation printed at Batavia .
s
$
Of the Belland, &c.
37
To whiten Bees- Wax, 5 April 3. 1674.
T n March or April melt yellow Wax without £ boiling $ then having feveral Pewter Difhes ready, dip the Outfide Bottom of each Difh in fair Water ; then dip them into the Wax, and take up a very thin Plate of Wax, the thinner the better: Take them off, and expofe them upon the Grafs, to the Sun, Air, and Dews, ’till they be milk white, turning them often. Try fome of them by fprinkling Water on them with a Cloth.
Whether white Lead may not this Way be made with very thin Plates,
Dr. John Carte’ j Letters to Dr. Grew, of the Belland, caufed by the Fumes of Lead \ and other curious Obfervations .
T thought it might be worth while to give you a fhort Account of a Diftemper in Der - byJJjire , very common among thofe, who are em¬ ployed in the Smelting-Mills, i . e. the Houfes where they melt the Lead down from the Ore j it is by the Country People called the Belland , but for what Reafon I cannot learn ; it is hard to give a concife Definition of it, becaufe it feldom ap¬ pears but under the Difguife of another Difeafe.
This Belland frequently imitates the \ tormina Ventris Scorbutica , but in a mod: exquilite Man¬ ner, which is ufually accompanied with extreme Coilivenefs, and a continued Suppreflion of U- rine : Sometimes appears like an Afthnia Convulfi- * yum , fometimes a continued and obftinate Dy/~ pfl(sa9 and often feizes the Genus Nervofiim , either
D 3 il1
or in
Of the Belland, &£.
In a paralytick Kefolution of the Parts,
Spafnis.
I t has a different EffeCt upon Men, according to their Age 5 if they come not to the Work of the Mills, till they are full grown, or of a mid¬ dle Age, they fuffer mofUy the aforementioned Pains of the Belly, or difficult Breathing. But if taken in while young, and growing, they are fubjeCt to the Palfy ■ their Limbs (efpecially their Fingers) being often irrecoverably refolved : Or fometimes have their Fingers fo contracted, as to render them (perhaps for ever) incapable of work¬ ing. Both which I have feen.
I could not be informed of any Specificks, they had for this Bifeafe ; but that a Decodtioii of Coloquintida , in Ale, was very common among them. 1 remember once, an old Man complained to me of the Bell and , it opprehed him in the Na¬ ture of an Afthma 1 advifed him to fulphurate Medicines, which did relieve him. The Contracti¬ on of the Fingers I have known cured, by often putting the Arms into hot Grains after Brewing.
I have not obferved, whether any of thofe, that are paralytick by the Bettand , die HeCtick, as Dr. Pope relates of them, at the Mercurial Alines In Firmly , but it feems not Improbable that they may.
This Biftemper is not only incident to Men, but other Creatures, as Horfes, Cows, Dogs, Cats, Hens, Geefe, &c. but, efpecially, Cats are fubjed to it : Indeed few Creatures,that are young, will live near thefe Mills without the Belland.
Bogs do in their Fits howl and tumble up and down, foaming like Epilepticks ; this the Peo¬ ple impute to the Pain of their Bellies.
1 k n o w a final! Rivulet, on which fome of thefe Mills Band, wherein Trouts have been caught, which have been fuppofed affeCted with
bet
Of the Belland, 39
the Belland , by the Irregularity of their Growth, their Heads being great and milhapen, their Backs crooked, their Tails very fmall, which, I am apt to think, might, proceed from their feeding on the Smith am or Dufi that is wafhed down at a Flood : For not only the Fumes, but alfo the Walkings of Lead Ore, and the Wafte (as they call it) i. the Dull that remains, after the Ore is melted, is very noxious to moft Sort of Creatures, and for this Reafon, they, that live near the Mills, dare not water their Horfes at the River, upon a Flood.
These poifonous Fumes are not only hurtful to Animals, but alfo injurious to Vegetables , for if the Snioak be driven much upon any one Place, it deftroys all the Grafs of it.
Now that the Belland in Men, or other Crea¬ tures, proceeds moftly from the Snioak, will be eafily granted $ but what thefe Fumes is. impreg¬ nated with, is the Queftion : Some fancy them to be Antimonial, but then, methinks, they ihoulcf have the fame Effedt with the Flowers of that Mi¬ neral, and I never heard that any of them were in¬ clined to Vomit. I am much more apt to . think, that the Mercury in the Ore is the Caufe, both be- caufe they, that work in the Mercurial Mines,, are fubjedl to the like Symptoms, efpecialiy the Pal¬ ly • and alfo I am told, that this Belland often begins with a Swelling of the Glands about the Throat, which, perhaps, if not prevented, might terminate in Salivation. But w hy Mercury fhould operate fovarioufly upon Bodies, differing in Age, is a (Queftion will hardly be folved, till it appear more plainly, whether it be nearer a-kin to Aka- lies or Acids : Its Effect \s eafily foretold in Bodies that abound with Acids, whether Scorbutick or Venereal ; but in younger Ferfons whole Hu¬ mours are more infipid, and their Blood freer from both fix’d Salts and Acids, it may, perhaps, fix
D 4 ‘ * itfeli
40 Of the Belland, &c.
itfelf upon the Nerves, as the cooleft Parts, and impede the Motion of the Spirits , but I had ra¬ ther hear others Reafons about the Caufe of thefe Things, than trouble you with my own.
So m e other Things 1 have b^en informed of by the Work-men, as that a little Spar mix’d with the Lerd Ore, promotes its Full on, I fuppofe, as the yellow Marchafite, that’s found with Silver, makes that Metal flow the fooner : That if there be any Holly-Wood in the Fire, it hinders the fluxing of the Ore, which is certainly caufed by the glutinous Sap of that Wood.
That the Smoak is obferved to follow the Water very much : I fuppofe the Coldoefs of the Water does condenfe the Fumes, as is feen in re¬ viving Mercury from Cinnabar. A blue Film is obferved on the Surface of thofe Waters, where the Smoak falls.
T n a t a Man may by wetting his Finger in his Mouth, cr cpmmon Water, draw it through melt¬ ed Lead or Iron, without any Prejudice.
*5V>, These Obfervations will feem barren, yet as good as I could make among thefe boorifh Peo¬ ple of the Peak , few of which can give a rational Account of either what they do, or fuffer, in fuch Matters.
I a?ny
Manchcfter, Oftob. 27. 1678.
u/>,
Tours ^ &c.
Part
Tr. H o o yCs W eatber-JVifer.
4!
Tart of a Second Letter to Tr. Grew,
Tec. 6. 1678.
SIR ,
Si n c e I writ to you about the Be l land , I have been in Derbyfhire ; all, that I could learn far¬ ther of it, was, that they are lefs fubjedl to that Diftemper in thofe Smelting-Mills, that ftand in an open and moveable Air, or that have large Ghimnies, and are not built clofe : I met with a Gentleman who told me, a Servant or two, of his had it very feverely in their Bellies, and were cu¬ red by taking the Salt that comes from the Sul¬ phur-Well at Knaresborough ; this Remedy is, l think, one of the likelieft I have heard of.
Tr. Hook’j Tefcription of his Weather - Wifer ; about Dec. y. 1678.
Th e Weather-Clock confifts of two Parts; Firft , that which meafures the Time, which S is a ftrong and large Pendulum-Clock, which j moves a Week, with once winding up, and isfuf- ficent to turn a Cylinder (upon which the Paper is rolled) twice round in a Day, and alfo to lift a Hammer for ftriking the Punches, once every j Quarter of an Hour.
Secondly , O f feveral Inftruments for meafuring the Degrees of Alteration, in the feveral Things, to if be obferved. The firft is, the Barometer, which | moves the firft Punch, an Inch and Half, ferving : to fhew the Difference between the greateft and j leaft Preflure of the Air. The fecond is, the Thermometer, which moves the Punch that fhews i the
Lf2, 2)re Hoo k *s Weather- Wifer.
the Differences between the greateft Heat in Sum¬ mer, and the leaft in Winter. The third is, the Eygrofcope, moving the Punch, which fhews the I : fferences between the moifteft and drieft Airs, The fourth is, the Rain-Bucket, ferving to fhew £he Quantity of Rain that falls j this hath two Parts or Punches ^ the firft, to fhew what Part of the Bucket is fill’d, when there falls not enough to make it empty itfelf j the fecond, to fhew how many full Buckets have been emptied. The fifth is,the Wind Vane , this hath aifo two Parts j the firft to fhew the Strength of theWind, which is obferved by the Number of Pvevolutions in the Vane-Mill, and marked by three Punches , the firft marks eve¬ ry ioooo Revolutions, the fecond every 1000, and the third every 100 : The fecond, to fhew the Quarters of the Wind, this hath four Punches ; the firft with one Point, marking the North Quar¬ ters, viz. N : N. by E : N. by W : N. N. E : N N W. N E by N. and N W by N. N E. and N W. The fecond hath two Points, marking the Eaft and its Quarters. The third hath three Points, marking the South and its Quarters. The fourth hath four Points, marking the W eft and its Quar¬ ters. Some of thefe Punches give one Mark, eve¬ ry 100 Revolutions of the Vane-Mill.
T h e Stations or Places of the firft four Punches are marked on a Scrowl of Paper, by the Clock- Hammer, falling every Quarter of an Hour. The Punches, belonging to the fifth, are marked on the faid Scrowl, by the Revolutions of the Vane, •which are accounted by a fmall Numerator, Brand¬ ing at the Top of the Clock-Cafe, which is moved by the Vane-Mill.
( 43 )
2)r. H o o iCs Contrivance of a Vejfel \ to " me a fur e the Quantities of Rain falling : Being a Bart of his Weather- Wafer in the preceding B after*
PROBLEM.
€ftc make a Vejfely which, when it hath re¬ ceived a certain Quantity of IV dter , jhall emftty itfelf
44 H 0 o k 9s Vejfel to empty ttfelf.
Le t the Veffel be a Triangular Prifm, as %, poiz'd like a Balance upon a Foot, fo that the leffer End may only defcend, and not the greater, by means of the Stop D. And let one of the Sides be ABD. From N, the Half of AB, draw the Line DN , and from of AB, draw MQ_ parallel to AB , therefore E fhall be the Cen¬ ter of Gravity of the Triangle ABD. And be- caufe AB is an open Side of the Veffel, fome Point between E and D, as G, fhall be the Cen¬ ter of Gravity of the whole Veffel j taking a Point at P near Q, towards D, ere (ft PC, and let C be one of the Centers of Motion, upon which^and the like oppofite Point in the other Side of the Vef- el, it fhall turn as a Balance. Secondly , By adding Weight in O oppofite to G, equiponderate the whole Veflel upon the Center of Motion C , there¬ fore DCN will be a Balance, whofe Center is C, and the Weights of equal Moment are G and O. thirdly , Draw the Line ST parallel to AB, fo that C may be the Center of Gravity of the Tri¬ angle DST.
Fir ft i Isay, if the Veffel be fill’d fhort of ST, the Side D fhall preponderate , if higher, the Side B , becaufe C is the Center of the Balance DCN, and the Centers of Gravity of all the like Triangles, lefs then DST (as DIL) are upon the Arm DC, and the Centers of all the greater up¬ on the Arm CN. Hence it follows, that becaufe it is flopp’d from defcending at D, the Veflel fhall reft till the Water rife above ST, when the Side, towards B, fhall preponderate.
2 d/y, Isay, if the Veffel be inclined towards B, the Part B fhall ftiil preponderate , let ABD be inclined, (C the Center as before •) fo that the Water, that lay before at ST, lies now as and let be a perpendicular Line, becaufe the
Triangles
2)r. Hoo k’j' Veffel to empty It [elf. 45-
Triangles DST, D kk are equal, but 7*S, the Tri¬ angle nearer the Perpendicular, is taken away, and £at5 being farther off, is added on the Side to¬ wards B , therefore that Side preponderates, and the more the lower it defcends, becaufe the Center of Gravity, of the Triangle £aT, runs farther and farther from the Perpendicular, till it runs over at B.
3 dly, Isay, that when a Part given of the Water is poured out, the Refidue {till preponde¬ rates, while it remains inclin’d. Let the Water be reprefented by the Triangle DRB in the Motion of pouring out, Part being run over ; the Center of Gravity of the Water, is ^ in the Line MQ_: and C « at right Angles to BR, will be the Per¬ pendicular, as CP wi}l be the Perpendicular when B is defcended fo Jow, that DB becomes horizon¬ tal, (that is, when all the Water mu ft be poured out) therefore CP is between CO and t/, but by ! Conftrucftion the neareft Point of MQ is without CP towards B, therefore v preponderates , there¬ fore the Veffel ftill inclines, till all be poured out. Therefore that, which was required, is perform’d.
| j C* . j s •• J
SCHOLIUM.
If it be requir’d that the Veflel, after it is
(empty, fhould return again to its former Pofition, there muft be added to the Point O yet more Weight at K, enough to reftore the emptied Vef¬ fel, in which Cafe a Triangle may be drawn as DBR, whofe Weight upon its Center v {hall equi¬ ponderate to K in O 3 it feems therefore, that the | Veffel fhould defcend no lower than till BR be i horizontal. But becaufe nothing that moves to- < wards an Equilibrium refts there, but is carried . further by the imprefs’d Force which it gains in de¬ fending
46 2)r. Hoo kV VeJJel to empty itfelf.
fcending to this Equilibrium.* as it appears in all Manner of pendulous Motions. And becaufe K may be lefs than any Magnitude affigned, therefore, notwithstanding the Counterpoife of K, it will de- fcend fo low, as to pour out ail s that is, having gain’d an imprefs’dForce in itsDefcent from B toK, there is noReafon but it fhould continue it beyond the Equilibrium to H and further.
Befides this, I find two other Contrivances of Dr. Hook's , among the Minutes of the Royal Society of April 1670. for meafuring the Rain that falls, in thefe Words : Mr. Hook fhew’d an Experiment in Mechanicks, which was a Way how to take notice of all the Rain that falleth, and was defigned as a Part of the Weather-Clock. The Contrivance is the fufpending the Bucket that was to receive the Quantity of Rain, that fell at any time (whether more or lefs) fo that according to the Quantity therein contain’d, the Place thereof fhould either be higher or lower, but certainly be determin’d. This was perform’d by a Counter- poife to the faid Bucket. The Counterpoife was contriv’d two Ways ; either by a String of leaden Bullets, fo order’d, that when the Bucket was quite empty, all the Bullets refted upon a Table ; but when there fell as much W ater into the Buc¬ ket, as equail’d the Weight of one of the leaden Bullets, then the Bucket defcended one Space, and one Bullet was lifted up ^ when twice as much, two Bullets , and when three times as much, three Bullets were lifted up , and fo for¬ ward, till all the Bullets were lifted up, and the Bucket' had defcended to its Place of Emptinefs ; whereupon the Chain of Bullets prefently defcend- ed, and lifted up the Bucket into its empty Place.
fDr. Hoo k V Vejfel to empty itfelf. 4 7
But becaufe this Motion proceeded by Jumps, and was not equable, therefore a fecond Contri¬ vance was alfo fhewn, which was this,
The Counterpoife to the Bucket, when empty, was a Cylinder immerfed into Water, Mercury , or any other Fluid. Which Cylindrical Counter¬ poife, according as the Bucket receiv’d more and Anore Water, was continually lifted higher and higher out of the Water, by Spaces always pro¬ portioned to the Quantity of Water that was contained in the Bucket. And when the Bucket was fill’d to its defigned Fulnefs, it immediately emptied itfelf of the Water, and the Cylinder plung’d itfelf into the Water, and raifed the Bucket to the Place where it was, again to begin its Befcent.
This Contrivance, here made ufe of, was declar’d to be very ufeful for making a new andufeful
I Beam, for examining the Weight of Bodies, with out any Trouble of adjufting, the Rifmg of the Cylinder immediately ihewing the determinate Weight of any Body, put into the Scale, without any farther Trouble.
Mr.
( 4« )
Mr. ToinardV Obfervation of the "Diffe¬ rence of Longitude between Paris and Breft, with Observations of Jupiter \r Sa¬ tellite Eclipfesfm 1679.
H. ' "
10 Bee. 79. A Paris a 12 50 08 A Breft a 12 22 37
Breft felon le grande Carte de France de Samfon del5 an 1650 eft plus oc- cidentale que Paris de degr. - 08 10 00
Qui valent le temps de - - 00 32- 40
Mais Fobfervation faite 10 Bee. donnede
difference - - 00 27 31
Par confequence la Carte qui eloigne
Paris de Breft de - - 00 32 40
Bont il faut oter la veritable difference 00 27 31 Sc trompe de - 00 04 22
Qui valent plus d5un degre & un cart.
3 Dec. 79. A Paris Fimmerfion du Grand 19 Satellite a - 10 53 23
A Paris Fimmerfion du Pre¬ mier a - - 09 16 03
Son gros camarade environ demie heure & demie call apres.
Mom
Of Hail-ftones that fell in London* 49
Monfeur ToinardV Obfervations of the Eclipfes of Jupiter V fir ft Satellite in 1680.
Satellites Jovis primi leu proximi immer-* fiones in umbram Jovis Parifiis, i68o„ Stilo novo.
Sept.
Q5toh»
|
D. |
H. |
M. , |
D. |
H. M. |
|
12 |
16 |
20 |
051 oh. 16 |
7 3o |
|
14 |
10 |
So |
21 |
14 55 |
|
21 |
12 |
45 |
23 |
9 25 |
|
23 |
7 |
I5 |
28 |
16 50 |
|
28 |
14 |
4° |
3° |
11 20 |
|
5 |
16 |
35 ! |
Nov. 4 |
00 w |
|
7 |
ii |
5 |
6 |
13 1S |
|
9 |
5 |
35 |
8 |
7 4° |
|
12 |
18 |
30 |
13 |
15 1° |
|
14 |
13 |
0 |
15 |
9 4° vel 3 S |
- — - . - . . -
2)r. H o o k's Account of the great Hail- ftones that fell in London, on May ig. 1680.
A t about 10 J Hour in the Morning, in Gre-* ‘ /ham College , I obferved the falling of a great Shower of Hail , concerning which, I obferved thefe Particulars.
The Day before, it rain'd almoft, all the Day,
I a gentle Rain, and, by turns, the fore-part of the Night. At about three or four o' the Clock in the Morning, was very much Thunder and Light- j ning, with an exceeding violent Shower of Rain 9 i whether any Hail then fell, 1 know not, being in Vol, L E Bed ;
jo Of Hat If ones that fell in London.
Bed ; but, by fome Circumftances, I believe there did, for there were found, in the Mornings feveral great Spots of Wet, which, 5tis probable, proceeded from Hail-ftones that fell down the Chimney. It continued to rain,, and now and then to thunder much, till about Nine ; then it clear’d tip, and the Sun fhone very clear, and
Of Hail- ft ones that fell in London, fx
theie was Icarce a Cloud to be leen ; about ten it began to thicken, and I heard the Thunder to the South Eaft ^ at about half an Hour after ten ! it grew very dark, and thunder’d very near; and 1 *oon after there began to fall a good Quantity of Hail-hones, fome of the Bignefs of Piftol Bullets i others as big as Pullets Egs, and fome above 2 j In¬ ches, and near three Inches over the broad Way ;
I the fmaller were pretty round, and white, like Chalk, or Sugar Plums ; the other of other Shapes: Some of the moil remarkable were thefe.
yx Of Hail-flones that fell in London*
Breaking many of them, I found them to be made up of Orbs of Ice, one encompaflmg ano¬ ther j feme of them tranfparent, and fome white, and opaque ; fome of thefe were to the Bignefs of near an Inch in Diameter, and were orbicular eve¬ ry Way. Some of them had the white Spot in the Middle, as A 3 others towards one Side, as B 5 and the Variety of white and tranfparent Spots ve¬ ry differing $ thofe, which exceeded thefe in Big¬ nefs, were made by an additional Accretion of tranfparent Icicles, radiating every Way from the Surface of the White Ball, like the Shooting of Niter, or toothed Sparre. Thefe in fome flood, as it were, feparate in diftindt Icicles, which were very clear and tranfparent, and had no Blebs or Whitenefs in them. Others of them were all concreted into a folid Lump, and the Interfli- ces filled up with Ice, which was not fo clear as the but whiter 3 and thereby one Side,
which, I fuppofe, was the undermofl, was flat, almoft like a Turnep ; and the Radiations appear¬ ed to proceed from the Ball in the Middle, more towards the upper Si^e, and mofl toward the Sides 5 the Edges and Top were more rough, and the Ends of the Stiria appeared prominent 5 which the Figures will better exprefs.
The Extent of this Shower I cannot yet cer¬ tainly learn, but have, by the Information of fe- veral, underflood it was feen above ten Miles off. I was alfotoldby feveral Perfons, that, a little before the Hail fell, there were was heard a great Noife out of the Sky, like the Shooting, or Emptying, of a Cart-load of Pebbles, as if they had fallen one upon another in the Air.
From the Manner of their Figure, I conceive, their Accretion was made by a Congelation of the Water, as they fell , that the final! white Globule in the Middle, about the Bignefs of a Pea, was
the
Of Hail ft ones that fell in London. 5-3
the firft Drop that concreted into Hail ; this, in falling through the Clouds beneath, congealed the Water thereof into feveral Coats or Orbs, till fome of them came to the Bignefs of Pigeons Eggss f°me white, fome traniparent, according to the feveral Degrees of Coldnefs it paired
I through, whilft they congealed ; that the laft Ac¬ cretion was made by a more violent and fudden Cold, in the lower Part of the Cloud, where they pahed through almoft a continued Body of Wa¬ ter. Other Varieties of their Forms, which were very many, I conceive, mutt: be made by their meeting with one another in their Pattage.
Notwithstanding Mr. Waller hath publijhed the Subfiance of this Paper , in Dr. Hook’s Life, p. 22. yet the Original may not be ttnaccep- table to the Reader , by reafon of the Figures Which the Doffor hath given of thofe monftrotis Hail-ftones ; which I, my [elf, faw falling, in °reat Numbers, in Great Lincoln’s-Inn-Fields, and no- '■ic'd to have fallen on May 19. 1680. one of which % Servant brought me in his Hand, as large as a Vurnep, and of the fame Shape, which I inftantly neafured with a String, and found the Compafs of he wideft Part to be above thirteen Inches j which r confefs, feems fomewb at incredible ■, but 1 1 think did it with great Care, and was not ifiifi ak.cn.
W. Desham.
E
3
The Reverend Air, Pasch all'; Letter to Dr. Hook, of an Earthquake in Somerfetfhire, dated Jan. 4. 1680. from Chedfey in that County.
Worthy Siry
Yesterday about feven in the Morning, X, being about to rife, took Notice of what feemed a fmart Guft of Wind, which was follow¬ ed with a Jog of our Koufe, and that immediate¬ ly with a very fenfible Shaking of the Houfe, and particularly the Bed in which 1 lay. I doubted the Fall of fome large Fiece of Timber, or Stone- Work, and caufed the Servants to make diligent Search all about for the Caufe of it j though not without Sufpicion that it might be an Earthquake. Before Night I became fully fatisfied that it was fo, for my Neighbours, many, obferved the like in their Houfes, though no Hurt was done. This Day, X hear, that it was in other Parifhes, one with¬ in a Mile of me, lying in the fame Level ; ano¬ ther above four Miles from me, lying on the fur¬ ther Side of an Hill, and which is a firm Rock. This Afternoon comes a Letter from an Acquain¬ tance of mine in Bridgwater , (two Miles from me, and on the other Side of their navigable Ri¬ ver) which fays thus, u I fuppofe you heard of" u the Earthquake, which happened with us this u Morning about feven a Clock : It fhook our ftrong Stone-Houfe fo, that 1 began to look u whether the Walls were fcattered or crafed, with a Noife, as if fome very great Thing had fallen u upon the Ground. One or two in Baft over (a.
Part of that Town on our Side of the River Ji * c were ready to leap out of Bed upon it, £s>c/a The Air was very calm, as being a frofty Morn¬ ing, upon the Snow lying, which fell the Day
2 before,
Smallnefs of the T articles of Water , yy
before. It lafted but a very fhort Time. I do not remember, for tkefe eighteen Years of my Abode here, to have known any fuch thing $ but I call to mind the Obfervation of Acofia , and others, that they do moll commonly happen in Places near the Sea, and fuch is our Country ; of which I meet many Arguments which perfuade, that it was, in thefe Parts of it, formerly gained from the Sea. If you fee my Lord of S — -, I prefume, it would not be unacceptable to his Lord flip, to have an Account hereof, feeing, ?tis likely, it will be a Matter of publick Difcourfe.
An Extract of Mr. LeuwenhoekT Letter from Deif, Jan , 6. 1680. Concerning the Minutenefs of fome Animalcules in the Waters.
•CinceI perceive you are pleafed with Cy fome of my Speculations, I have, here-
\ withall, tranfmitted alfo a Copy of that hafty Calculation, which, at the Defire of the Honou¬ rable Chnftantine Hygens van Zntichem , I drew up for him in Writing , which was this which follows.
SIR,
IT have been often confidering of the exceeding J Smallnefs of thofe Yeflels, of which the Si¬ news and Mufcles of thefe fmall Creatures mult be furnifhed with : That which put me upon this Speculation was, the Query put to me. Whether 1 could, by my Microfcope, difcern the Particles of which Water doth confift ? To which I fre- 1. quently gave this for an Anfwer, That there are in I the Water living Creatures, many Millions of
E 4 Times
§6 Smallnefs of the T articles of W ater.
Times fmaller in Bulk than a fmall vifible Sand, Further, That each of thefe Creatures, though I have not, as yet, been able to difcover their Paws, Finns, or the like Inftruments, by which they move, muft, neverthelefs, be furnifhed with feme Kind or other of Organs, fit to produce that Mo¬ tion. And that thefe Organs muft be made up of Veins, Arteries, or Veflels, to convey Nourifh- ment to them, and in Sinews or Strings, to ftir and move by, (3 c. If fo, then by thefe Veflels the Water muft find its Paflage, and confequent- ly the Particles of Water muft be confiderably fmaller than thefe Veflels, other wife it could not freely pafs therp , now the whole Animal itfelf, be¬ ing but fearcely vifible, we muft conclude, thefe their Veflels muft be wholly invifible, and how much more invifible muft be the Parts of Water that move in them , infomuch that I am very con¬ fident, that no Man will ever be able to attain, by the Help of Microfcopes, to difcover and diftin- guifh the Particles of which Water doth confift.
Now that there are fuch Creatures, that are fo many Times fmaller in Bulk, than a fmall vifible Sand, I prove by thefe following Obfervations and Calculations. 1 do generally fuppofe (becaufe, as far as my Sight was able to help me, in taking the proportionate Bignefs, I fo judged it) that about 3 or 400 of the fmalleft of thefe Creatures, laid one by another in a Line, may make the Length of the Diameter of a middle-fiz5d Grain of Sand. I here fhall make ufe only of the lefler Number, viz. 300 $ which multiplying cubically, I find the Produd to be 27000000 » whence it: follows that there will go the Quantity of 27 Mil¬ lions of thefe Animals, to make the Bulk of one: fmall Grain, (sic. If we then fuppofe that eighty of thefe Sands, laid one by another, will make
Smallnefs of the*P articles of Water. 57
but one Inch in Length, then there will lie in the
Space of a Cubical Inch no lefs than 512000 of thefe Sands, each of which being fuppofed to be as big as 27000000 of thefe Creatures, the Inch
_ * e • ®
Cubical will contain no lefs than 1 3 824000000000* almoft fourteen Millions of Millions.
I have confidered alfo of the fmall Veflels, that ferve to compofe the Parts of our Bodies* and conceive them to be Pipes a thoufand Times fmaller than an Hair of a Man’s Head ; and by a Brafs-Rule, curioufly divided into Inches, and each Inch into thirty Parts, endeavouring to find* how many of thefe Hairs Breadths would make an Inch, I found that twenty Hairs would lie one by another in the thirtieth Part of an Inch, and therefore 600 in an Inch 5 and meafuring my Body, I found that one Part, with another* equaled a Cylinder of eight Inches Diameter ; fo that thefe Proportions confider’d, I find, that
one of thefe VeflTeis muff be 360000000 fmaller than a Pipe of an Inch Diameter, and, confequently one Part of the Body being equal to a Cylinder of eight Inches Diameter, which is 64 Times as big as one of an Inch, the Cylinder of the Body is bigger than the Cylinder, of one of thefe Veilels,
^ e •
no lefs than 23040000000. Now if the Veflels of the Bodies of thefe fmall Creatures, in Pepper Wa¬ ter, ihould hold the fame Proportion to their Bo¬ dies, how can we conceive the Parts of the Wa¬ ter Ihould be difcovered, that ihould move in thofe Yeifels,
i * f
Reifilius
( 58 )
Reifeiius his Letter to Dr. Grew, concern¬ ing a Man's periodical Lofs of his Sfeech} from Stutgard, March 6. 1680.
At enim, ne fine fymbolo coram altar! veftro fandtilTimo appaream, appono hie Cafum quendam mere naturalem quidem, ut mihi vide- tur, propter multos fimiles affedtus periodicos Cephaleos pidtum, Convulfiones, Colicas, ut de Febribus nihil dicam, fed rarum tamen, ob tarn conftantem tamqj multis annis durantem perio- dum, uti obfervatus fuit a Collega meo exami- nante in prefentia Principis noftri aliorumque magnatum Novembri menfe prasteriti anni. Cujus caufam, cum neque mihi neque aliis detur aflequi, ab Societatis .Regime Judicio difeere gaudeo & rogare audeo. Quomodo a fermentatione qua- dam ut in Febribus aliifqj morbis deducenda lit hate affedtio, haereo. An a coeli meridiano vi« gore trahendum malum feu bonutn, dubito, cum olim aliis horis & inordinate notata fit haec af« fediio. Symptomata tamen, quae quondam ante- grefta, morbofum quid innuunt. Hie talis eft. Georgius Algaier , Georgii Algaieri Cauponis Jefin~ gee prope Kircfemium in Ducatu IV irtenbergicoy filius temperament! Cholerici, annorum 25, jam ante annos quindecim fefto S. Stephani ftatim poft ccenam, adeo male toto in corpore fe habuit, ut nul- libi fe continere potuerit. Anxietas cordis erat tan- ta, ut, nifi per Vomitum ingentem levatus fuiflet, fuffocari fibi videretur. Hora poft vomitum uni- ca pratterlapfa melius agebat, at per totum trium menfium decurfum valde triftis & melancholicus, interdum etiam quafi terrore percuflus evadebat. Elapfo hoc tempore, primo faltim per unum fere momentum vocem & loqudam, quam prius accu¬ rate
Of a Man's lojtng his Speech , 8cc. yp
rate callebat, amifit, ut ne verbulum quidem? neque ullam vocem emittere poftet. Quotiefcunqs vero loquela amittebatur, toties turn, (quod tamen ultra dimidium annum non duravit) e ventriculo? aliquid furfum, fauces verfus reperi fentiebat. Atq; uti primum vocis & linguae fuppreffio faltem momentanea, lie eadem poft indies indiefq; crefeere incipiebat, ita ut a momento ad femihorium to- turn, duas, tres, & ultimo ad 23 Floras, inordinate tamen, duraverit. Tandem typum adeo conftan- tem habebat locutionis reftauratio, ut jam per 14 annos,non nifi fmgulis diebus abhora 12 meridians, per horse integrsefpatium, ad primum fcil.Pomeridi- ; anse punftum ufque loqui poffit. Nee falli poteft ( hominis Horologicus fenfus h ora rum tranfpofiti- j one, cum vel nullis campanis fonantibus terminum l horse duodecimse ufque ad primam femper& quam : accuratiffime obfervet. Notandum etiam quod dum loqui poteft patiens, aliquantifper balbutiat, quin & turn extra turn intra locutionis tempus lin- guam ipfam non fatis volubi liter queat movere, Prseter amillionem vocis & loquelse nulla de acti- one queritur, fenfus turn interni turn extern! funt integri. Accuratiffime femper audit, unde vel geftibus vel literis (feribere enim feit fatis intelli- genter, ut ipfum hoc imitatione expreffum propria manuferiptum teftatur nomen Georg Ulgryer Jefingus') ad interrogata cuivis quantum poffibile eft refpondet. Vixit alias hactenus omnimodd fanus, nec ullum morbum, excepta Febri, qua ante tres menfes vexabatur, quotidiana ; cujus pa- roxyfmum inordinate jam mane, vefperi, jam eti¬ am noeftu fuftinuit, paftus eft ; neque typus amiffe loquelse ex Febri minimum mutatus. Vivit etiam- num poft febrem fanus omnino & incolumis. Huc- ufq, Cafus Muti periodic e loquentis.
Mr.
( 6o)
Mr. P i g o t in his Letter to Dr. Hoo from Oxford, Nov . 26 . 1681. faith ,
Mr. Cafwel, /« his travels with Mr. Adamss obferved Lidford-Bridge, or ££00; Dart- more in Devonfhire, whofe Plane is level with the Ground , yet 59 Feet above the Water 3 that runs fwiftly under it.
At Droit wych in Worcefterfhire, he vifited the SaluSprings 5 which he founds upon t %fie3 to be far falter than the Sea. they have three in the town 5 clofe by afrejh River Side3 and could have fnore3 but that the Merchants will not permit any more ? to keep up the trade . He tells me3 the poor dirty Women3 that work at the Salt-Houfes3 are ne** ver troubled with Lice 3 Fleas 3 or Flies,
Mr.
( <51 )
■t
||
I
;!
II
m
Mr. LeewenhoeckV Letter in Nov* i68r, of the Structure of Hair ; of the Excre¬ ments , &c.
/ R,
Th a v e (hewed that the Cortex of the Hair of an Elard Hart, was compos'd of Globules.
I found the fame of my own Hair. I have fince found it like the Bark of a Tree of Globules, but irregular from the fqueezing of the Hair. The Subftance of the Hair is made of Threads , fome judge the Hair hollow, others to have Marrow ; but viewing a Hog's Hair, 1 found the Hollownefs of thofe Hairs from Cleft. Hair grows by Pro** trufion, not as Plants, being thruft continually forward, from within the Skin outward j what was within moift, expos'd to the Air, dries and fhrinks, and the outwardSkin hardening,the inwardT hreads, upon Ihrinking, cleave into one or more Clefts, which feems like Marrow. In a Piece of Hog's Hair the Threads appear plain, even in a common Microfcope, but bigger in Proportion to the Cir¬ cumference for Eafe , the Threads were but few, from the Roughnefs of the Razor. By thefe may appear their Miftake, who aflert Hairs round , 'tis rather true, they have all differing Figures. A Friend vifiting me after a Fit of Sicknefs, where¬ by he had loft all his Hair, complain'd of a great Itching all over his Skin, yet his Stomach was good, which the Docftor attributed to a Sharpnefs of Blood 5 which I rather afcribed to the filling of the Body, and from the new growing of the Hair in the Pores, whence it had fallen by his Difeafe, the Pores of which being clofed, the new Hairs, thrufting againft the Cuticula , caufed the Itching. I my fe if have been fo troubled in the Spring,
which.
6% Of the Structure of Hair , &c.
which, I conceive, to proceed from the fame Caufe, being my feif hairy, and fhedding them yearly, as, I conceive, moft Men do ; this I ob~ ferved in two Parts of my Body, alfo in three Places of my Hand, where I have fhorn off the Hair, and found, that fome Hairs grew, others not ^ fome fell out, and I could pull them out without Pain j alfo, that thefe, which fall out, have thin (harp Roots , thofe which ftay, thick ; alfo fuch, as have no Hairs on their Body, have Pores, and an Hiding Matter, not fo fit for Hair. This ap«* pears like black Specks, and are fuppofed Worms , and fome Doctors of Aken0 did prefcribe this Man to ftand with his Back to a Fire made of Oak, and anoint his Body with Honey, that by Means of the Sweetnefs and Warmth, the Worms may come out, and fo be cut off with a F.azor, as the Gentleman Patient himfelf told me ; hereupon I try'd to prefs, both out of my own, and out of another Man's Nofe, thefe fuppofed Worms, which feem'd, from their Shape, much to favour the Opinion, feeming to have a Head which pro¬ ceeded from that Part of the Hair, which was next the Air, it being browner than that within the Skin, but no two like one another. I obferv'd all its Parts, but found nothing like an Animal $ but in feveral I found fmall Pieces of Flair, fome 25, others 100 Times thinner than a common Hair. Plence 1 concluded, the fuppofed Animals are only the places of thofe Hairs fill'd with the ufual Food of Flairs , my Opinion is confirm'd by new-born Children , over-grown with Hairs, which, I fuppofe, from too much Nourifhment, grow hairy, but when they want that Supply, the Hairs fall out, and grow not again.
In aLoofenefs I view'd my own Excrements, and took notice of what I eat and drank, it confided of
clear, yellow, roundifh, irregular particles, alfo of vaft
Quantities
Of the Structure of Hair , cxc. 63
Quantities of Globules, like thofe of Blood, fix together equal to j of the whole 5 others but 7! of a Blood Globule : Thefe I found in a tranfparent Liquor, in which were many Animals, as big as a Globule of Blood, their Bodies oblong and flat, with many Feet underneath, with which they moved quick; like aPifs-a-bed agairift a Wall, tbo* they moved their Paws quick, yet they went but flow. Once I found but one in the Bignefs of a Sand, at other Times, 4, 5, 6, 7, or 8. I have feen other fhap’d Animals, (but of the fame Big¬ nefs) like River Eels ; thefe were very numerous, and fo fmall, that 5 or 6oo, extended in Length, would not reach the Length of a River Eel ; thefe Wriggled like a Snake, very quick, like a Pike {hoot¬ ing through the Water. At another Time, I faw Multitudes, 200 Times lefs than a Blood Glo¬ bule, the Axes being about one to fix, and I am confident, I have feen above 1000 living Animals, in the Bignefs of a Sand, fwiftly moving, and of three or four feveral Sorts. Some have thought, thefe Animals might pafs into the Blood ; but, I conceive, the PafTages of the Blood are fo fmall, that though the Animals were 1000 Times left, they could not pafs. My ordinary Excrements, mixed with a clear Liquor, had no Animals; but when thinner than ordinary, it had. I found al- fo Parts of the Food I had eaten, undigefted, as the Pipes of Afparagus, the fofter Parts being di- gefted.
This Summer, in our Meadows, I have of¬ fer ved the Dung of Cows, Horfes, c Sc. frefh, but found no Animals. It confifted of Multitudes of Globules, fome others 77 of a Blood Globule, in a clear Liquor. In May laft, riding my Mare ,i hard, I obferved the laft thick Part of her Urine, and found, the thick Aih Colour of it was caufed by a great Variety of differing Globules, fome as
bis
1
6 4 Dr. Ho orV Enquiries for Jamaica.
big as thofe of Blood, and thefe compofed of fix* The firft of thefe were like a clofe-grown Bunch of Grapes, and though not perFedt round, yet I call them Globules.
Dr. Hoo kV Letter to Dr. Trapham, of Enquiries for Jamaica^ Feb . x8. 168*.
S I R, .
I t will be a great Obligation to the Royal Soci~ ety , if Dr. Frapham^ or any other ingenious and knowing Perfon in 'Jamaica , will pleafe to communicate any curious Obfervations they fhali make, concerning any Part of Nature , as con¬ cerning the Temperature and Qualities of the Air, the Seafons, Winds, Storms, Hurricanes, Rains, Hails, Dews, Mills, Fogs, Be. the Heats, Colds, Be. of the Seafons j the Qualities of Springs, Rivers, Lakes, Be. the Defcription of any of the Animals, Birds, Bealls, Fifties, Ser¬ pents, InfecSs, or of any of their Qualities or Ufes, for Food, Phyfick, Pleafure, Be. The Defcription of their Vegetables j as of their Herbs and Shrubs, whether of the Land or Sea , of the Trees , their Ufe in Food, Phyfick, Building, Dying, Perfuming, Firing, Joinery, Turning, Bows, Be. The Defcription of any of their peculiar Stones, Minerals, Ores, Metals, Clays, Earths, Sands, Be. of what Nature, what Ufe made of them, Be. Alfo to inform them con¬ cerning any accurate Obfervations, that have been made of any Eclipfes of the Moon, and particu¬ larly that of the nth of this Inllant February ; of the Variation of the magnetick Needle, from the Meridian, or North Point ; of the Times of the Tides, both Spring and Neap, and of the
Height
Of the Fibres of the Mufcles , Sec, 6f
Height it rifes ; of the Currents, what, when, which Way 3 of the Depths and Soundings of the Seas thereabouts, and whatever of this Kind fhall be communicated ; or if any curious Jewels, Shells, Seeds, &c. fhall be fent, the Society will not only pay the Charge of Freight, but any o- ther way gratefully acknowledge the Favour that the Communicator fhall defire, either by record¬ ing it in their Regillers, or publifhing it in their Hiftories.
Mr. Lewenhoek'j* Letter to Mr. Oldenburg, receiv'd from Dr. Crowe, Aug. 14. 1682. Of the Fibres of the Mulcles, Dura Mater, Brain, and Moxa.
Excellentijfime ac Eruditiffime Fir .
C^ratissimas, praeterit^ menfis decima 1" prima ad me datas, literas accepi, In quibus humanitatem Nobilitatis Vefte, dominorumque philofophorum vifam, grato animo agnofeo.
I n literis 22da Februarii feriptis, nobilitas veftra inquit, amicorum quofdam optare, ut fumma cum exadtitudine obfervarem fibras muf- culorum carneas, ut & corticem, medullamque cerebri.
In literis meis. Anno 1674, prima Junii da- tis, dixi : Fibras mufculorum carneas ex valde parvis confiftere globulis : Sed quo nobilitati veftrse reliquifq^ amicis magis fatisfaciam, omnes prsece- dentes meas obfervationes rejeci, firmiterque pro- pofui, de novo, dare ac perfpicue eas, oculis me¬ is mi hi perfpiciendas, fumere.
F
Inter
66 Of the Fibres of the Mufcles , 8cc.
Inter alias, carnem vdccinam accepi, quain, acutiffimo cultello, in frufta concifam, per mi¬ cro! cop ium a membranulis fuis feparavi, quo per- radio, turn primum mihi nude ac dilucide apparu- it, tenuifiima ilia membranula, cui fibrae carnese quad involute, aut intextse jacent, cujus etiam Anno 1674. pri m&Junii in literis meis memini, dicens : Membranulas illas ex tot ftriis ac fibris confiftere, quad nudo oculo omentum alicujus beftias afpiceremus. Eafdem membranulas jam propius obfervans, totas illas folummodo con¬ fiftere ex fibris tranfverfim inter fe mixtis, compe- ri, quarum qusedam, in oculo meo, decies, vicies, & tenuiffimae quinquagies tenuiores pilo. Cogi- tabam, num quaedam crafiioris generis, quae in ramos fe difpergebant, non eftent vafa lympha- tica.
Sublatis, a praedidlis fibris carneis, praeno- minatis membranulis, eas nude ac perfpicue vidi, quae in hac carne erant ad craflitiem communis ca« pilli. Ubi fpiflae ac denfae, rubicundae erant j ubi tenues ac difperfe jacebant, magis apparebant pellucidae.
V a r 1 a obfervandi methodo ufus fum, parti- eulas carnearum harum fibrarum videndi, perpe- tuoqj inveni, eas ex talibus compofitas partibus, quibus aliam quam globulorum figuram appropri¬ ate nequeo. Imo & minima fibrarum carnearum fruftula, grano arenae aliquoties minora, coram vi- fu meo in plurimas divifi partes. Praeterea etiam obfervavi, carne adhuc recenti & humida, quod, turn comprefiis vel fricatis carnis globulis, illi glo- buli refolvantur & conjungantur, quafi oleagino- fam, vel ali.quo mode concretam, videremus, ma- teriam aquofam.
H 1 globuli, ex quibus fibras carneas confiftere dixi, adeo exigui funt, ut (juxta ocuiiim, meurnq; vifum, judicium ferens) dicam 1000000 non con-
fedturos
Of the Fibres of the MufcleSj &c. 67
fe&uros unici arense grani, aliquo modo grandio- ris, quantitatem.
E t quamvis in mentem veniat, me antea Mo bilitati Veftrae fcripfiffe, particulas, ex quibus ca~ ro, adeps, ofla, capilli, &c. coniiftunt (quae a me globuli vocantur) non effe veros & proprie fic dit¬ tos globulos, fed figura globulis proximos, eadem tamen hie repetam: Ex. gr. Imaginetur quis fibi, fe magnam veficarum ovinarum, vel aliarum, aqua repletarum habere quantitatem : Else veficae quam- diu, ab omni parte, ab aere circumdantur, rotun¬ ds? erunt : Sed imaginemur nobis, eas promifeue & indiferiminatim in vas aliquod injici : Quo fadto, veficae, globofam, quam in aere habuerant, ro~ tunditatem, non fervabunt, fed a fe invicem coni- preffae, nullum vacuum ( fic loquendo ) locu relinquent: Et fic quaevis vefka aliam, ob Hex!-' bilem fuam mollitiem, accipiet figuram. Sed quae in vafe fupremse jacebunt, in quantum ab aere ampledbuntur, globofam retinebunt rotundi- tatem : Idem de globulis carnis, propter eoruni * mollitiem, fit judicium.
Piam Matrem obfervavi, comperique membra- nam hanc, variis fanguinis vafibus intertextam, prseter ea quae nudo oculo, cerebro injacere, cer- nere pofluimis, (prsecipue feparatione Piae Matris & cerebri fadfca,) & inter ea venae admirandse Sc incredi bills tenuitatis : Et quantum dijudicare poffum, membrana ilia ex admodum exilibus con- fiftit fibris. Elterius vidi, praedidbas multiplices I venas, per membranam hanc difperfas, ramos fuos per cerebri fubftantiam quoque difpergere : Eo : modo, ac fi nobis imaginaremur diverfas & fuper- , ficiei terrae palmitibus fuis injacentes vites (quas tvenis Piae Matris comparo) eafque ubique ex pal- mitibus fuis radices, in plurimos difperfas ramos, site in terra egiffe. Terrain hie mihi imaginor fub-
F 2 ftantiam
I
i
68 Of the Fibres of the Mujctes , See.
ftantiam cerebri, & radices, venas per cerebri fub- ftantiam difperfas.
Accedens jam ad partes ipfius cerebri, ad- hue affirmarem, id, praecipue ubi paululum com- preffum ac compadtum, non nifi ex globulis, & non ex aliis confiftere partibus : Sed ubi ra- rum ac tenue, cultro concifum aut feparatum, fefe oftendebat dilucidiflima materia, quafl ole¬ um fuiffet, qtiam videns imaginabar mihi cultro id caufatum, globulofq; cerebri difruptos aut fradtos. Verum enimvero perfeverans in obfer- vando, non tantum beftiarum, fed & pifeium, & prsecipue quidem Afelli majoris cerebrum, clare perfpexi materiam illam oleaginofam, non fuiffe cultro ex difruptione globulorum caufatam, fed revera efle materiam feparatam, cui praedidti cere¬ bri globuli quafi injacebant. Ulterius vidi, fed clariflime in cerebro Afelli majoris, prsedidtam olea¬ ginofam fubftantiam, reapfe etiam ex globulis, fed multo minoribus, quam ipfius cerebri, con¬ fiftere.
Primo nominati globuli cerebri, meo judicio, circumcirca, globulis fanguini ruborem afferenti- bus (ex quibus fanguinem confiftere dixi) magni- tudine aequales funt. Hi majores globuli, ex maxi¬ ma parte cerebrum conftituentes, refpedtu globulo¬ rum fanguinis, valde irregulares vel inequales exif- tunt. Hujus rationem exiftimo vel globulorum fir- mam inter fe, aut cum vafibus conjundtionem, vel eorum mollitiem, adeo ut fe feparari non finant, quin (fic loquendo) a fe invicem difeerpantur, ubi e contra globuli fanguinis in fluidiori materia mo- ventur, & propterea etiam, globofam fuam ro¬ tund itatem, quando in latiori fpatio exiftunt, re- tinent.
I n animum fubit, me antea temporis obfervafle cerebrum Anatis , & turn judicaffe, cerebrum ex parte confiftere ex filis, aut admodum exilibus
vafibuS'
Of the Fibres of the Mufcles , &c. 6$
vafibus. His filis vel vafibus poftea mihi fiepius oc- currentibus, turn temporis & idem judicabam, ea Jtantum produci per firmiftimam globulorum (ex quibus cerebrum folumtnodo confiftere putabam) inter fe unionem, & qui minima extenfione fic in fila mutarentur. Sed obfervationes meas per in¬ tegrum menfem continuans, clare admodum vidi, multiplices valde, & fupra modum exiguas venas (de quibus antea certus efle non poteram) eas in beftiarum cerebro exiftere, & revera venas efle, licet cognitu admodum difficiles. Verum obfer- vante, exadtiufque infpiciente me Afelli majoris ce¬ rebrum, multiplicia ijla minima vafa, aut venulas, quae fupra modum pellucidae, clare mihi oftendi : & multas, licet in ramos difperfas,& quindecies vel vigefies filo bombycis exiliores, tamen cognofcere potui : Horum cjidtorum vaforum vel venarum maximam mukitudinem, in quantitate cerebri ad magnitudinem arenae, vidi : Praeterea Sc vafa fan- guine repleta,vel quaembicunda apparebant,ut eti- am vafa ad craffitiem unici fili bombycis, Sc infuper pellucida vidi.
Has c e meas obfervationes circa beftiarum ce¬ rebrum perfequens, vafa ante nominata, admodum perfpicue quoque oftendere potui, eaque fumma cum admiratione vidi, partim ob ingentem multi- tudinem, partim ob fupra modum fummam eorum exilitatem. Si enim juxta oculum meum judicium feram, dicere teneor, quod, fi globulus, fanguini ruborem afferens, in odto eftet divifus partes, Sc u- naquaeque ocftava pars eftet firma Sc folida, ne una quidem harum partium haec vafa tranfire poftet. Et quamvis diverfts vicibus prsedidfca cere¬ bri vafcula mihi perfpicue ob oculos pofueram, in obfervationibus meis circa ilia tamen continuavi, & quo penitius ac faepius obfervarem, eo exacftius admodum multiplicia ilia vafcula, cum ipforum ramis (qui adeo infirmi ac debijes, ut minima con- tmftatione difrumperentur) dignofcere potui.
F 3 I h x E k
y o Of the Fibres of the Mufcles , 5c c.
Inter di&os globules, ex quibus cerebrum ex parte confiftit, globulos fanguinis jacentes vidi, qui, ob perfectam rotunditatem, clare a globulis ce¬ rebri diftingui ac dignofci poterant : hos fanguinis globulos opinabar e fanguinis vafibus per cerebrum difperfis, & cultro concifis, effiuxiffe.
Inter corticem & medullam cerebri, aut par-? vam, aut nullam fere, differentiam5obfervarequeo : praefertim cum paululum rariorem, & tenuiorem, earn mihi videndam fumo : tantum dicam, venas, aut vafa corticem cerebri permeantia, aliquo modo fubfufci vel fubnigri ede colons, ubi e contra vafa medulla? cerebri erant dilucida ac pellucidiora.
I n cerebro, fed plerumque incortice,tam exiles ac rubicundas, ex majoribus procedentes, venulas vidi,utcapere nequeam, quomodo globuli fanguinis eas permeare podint : & ultra, quo padto globuli paulo rariores, & feparatim obfervati, fermenullius faltern admodum modici eilent coloris, ubi e con¬ tra fanguis in hifce vafibus ruberet. Imo & per ipfas venas, in fubftantiam cerebri proximate color ille rubicundus penetrarat, eamque infecerat. Sed ammo revolvens, me in obfervandis Fediculis fepe vidifle, quando Pediculum efurire feceram, ipfique prope fame confebto, jam fanguinem fugendum darem, ipfum non potuide confumere fanguinem, aut etiam ejicere ; quo evenit, ut globuli fanguinis rubicund! liquefierent, & in materiam fluidiorem refolverentur, & fic per totum Pediculi corpus, imo per ipfas ungulas & cornua difpergerentur,omnibuf- que partibus ruborem afferrent. Caufam non con- fumpti fanguinis opinabar, intefrini aut parvarum in Pediculo venarum exficcationem, defedtu aliment! caufatam: quo debitus ac ordinarius fanguinis mo- tus fuit impeditus, nec jufto modo per totum cor¬ pus vehi potuit. Sed memini,hanc fanguinis mu- tationem, in fanguine, in vitro per aliquod tern- pus, fervato, aliquando etiam a me obfervatam, 1 “ Et
Of the Fibres of the Mufcles , &c. 71
Et idem in parvis cerebri venis accidere poffe opi« nor ( quamvis adeo exiguse ffnt, ut globulus, ro- tunditatem fervans, penetrare nequeat) ut refolu- tis globulis, & venae rubrse appareant, & cerebrum adjacens rubore tingatur.
Medullam fpinalem Vituli, Ovis, Gallinae, ac Afelli majoris etiam obfervavi, quam ex iifdem cum cerebro partibus confiftere comperi, cum hac folummodo differentia, quod prater globules,
| quos cum cerebro fpina medulla communes ha- 1 bet, in hac ingens globulorum oleaginoforum & pellucidorum numerus, ac diverfe magnitudinis i jaceret. Quidam enim quinquagies majores reli- quis, ac prseterea admodum molles, ac fiuidi. Ca>
I terum medullse fpinales multis ac fupra modum 1 tenuibus inftrudH erant venis aut vafibus. Prsete- 1 rea hie per medullam fpinalem difperfe erant fi- i bras col oris fubfufei, & ad craffitiem capiili, quae- i dam vero tenuiores : quibus vilis imaginabar mihi 1 in initio, num qusevis fibra forfan non effet t vena : fed fumma cum exadtitudine penitius in- : fpiciens atque obfervans, comperi, quamvis fibram non efle vas, fed fmgulas earum confiftere ex aliis valde exiguis fibris aut vafibus fibi invicem adja- centibus, inter quas fibras pellucidiflima videre e- rant vafa ad craffitiem fili bombycis. Hie turn : opinabar, an haec vafa non eflent ea, quae fpiriti- 1 bus animalibus per medullam fpinalem vehendis inferviunt.
Hie funt,clariffime ac nobiliffime vir,quse poft I ultimos, indefeftos, & exadtiffimos labores, hue- . dum in cerebro, &c. detegere valui.
U t 1 dixi antea, quo pacto multae venas fibi in¬ vicem adjacent conjunct quaff una tantum eflent ‘ vena, ffc illud mihi non tantum occurrit in medul¬ la fpinali, & interdim quoque in cortice cerebri :
! Verum etiam in frudtibus, & feminibus, praefertim in Gaftanearum venis. Ut & in cortice & puta-
F 4 mine
Of the Fibres of the Mufcles , &c.
t amine Amygdali: in fecundanigri piperis mein-8 brana 5 In putamine Avellanae nucis duro5 & mem- brana qux intus inconcavoei adhseret, &in molU eortice cui nucleus injacet involutus : ubi quidem 15 aut 20 tenuiffima vafafibi invicemadjacentia vidi. Btiam in membrana nucleum Juglandis immediate ampledtens. Omnia hsec vafa ex continuata tor- tuofitate compofita funt5 eo modo ac fi nobis i ma¬ gi naremur tenuiffimumaliquod filum sereum aut ferreum craffiori preffim circumvolutum (in for- mam qua fuftis vel baculus fifths iterum fune col- ligatur) poftea extradto craffiori filo, tenuiffi- mum illud quod ei circumvolutum fuerap, omnes gyros ac circumvolutiones retinebat. Eodem modo (ut dixi) tenuiffima in prsenominatis feminlbus & frudtibus vafacontortavidi. Prseterea inMalo & Pi- ro tenuiffima fibi invicemadjacentia vafa obfervavi. Annus jam prseteriit5 cum in sedibus fuis, no- bilis dominus Conftantinus Hugenius a Zuli- chem, mihi monftraret Moxam , addens, quo pacSo inuftione iftius herbae podagra fanaretur: Aliquan- tulum hujus ilc dicflce herbae Moxse mecum domum retuli, carpoque manus impofitum juxta praefcrip- tum urendi modum, combuffi ( ex curiofitate ni- mia, nam podagra non divexor) quo extraordina- riam hujus combuftionis effedlum detegerem, ob¬ fervavi autem cuti3 in loco uftionis, injacere mate- riam flavam ac oleaginofam, quam principio judi- cabampec combuftionem cutis caufatam. Verum hanc cutis inuftionem intermittere coadlus fui, non ob dolorem, fed fanationis difficultatem : fi enim tam facile fanare poffiem5 ac vulnus ex incifione cultri, (quod colligatum ac confutum fanatum aeftimo) fepius hanc inuftionem iterarem. Per mi- crofcopium Moxam examinavi, firmiterque fentio Moxam non efte herbam ex optima teme pharmacis artificiofe paratam, ut autumat dominus BiitT- choff in tradiatude Moxa p. 52fedfolummodo va*
porem
Of the Fibres of the Mufcles , Sec. 7 3
porem aliquem ejedtitium alicujus frudtus, ficuti in malis Perficis, Cydoniis £jjc, lanofam videmus fubftantiam cortici adhaerentem. Cogitaram etiam me de frudtibus quibufdam colledturum herba$ moxae quodai* modo fimiles, fed hucufque efficere 1 non potui.
Moxa, quoad figuram, goflypio refpondet : licu- j ti enim inter pilos, capillofve, & lanam, nulla, niil \ quoad craflitiem & longitudinem, differentia, ut- pote ex globulis confiftentes,& ad rotunditatem in- clinantes: aeque parva inter moxam & goflypium dif¬ ferentia, & ilia & hoc enim duobus planis gaudent lateribus. Eandem figuram, lanofum illud quod interne rubri corticis caftanea? convexo adglutina- tum, oftendit : in hoc tantum differens, quod moxa multo fubtilior fit goflypio, hoc caftanes? lanofi- tate. Moxam, cum inuftio manus non placeret, juxta & goflypium, forfice parumper difledium, quo facilius ignem perciperet, chartse anguftse im~ pofui, & haeemoxae & goflypii combuftio fibi invi- cem exadie refpondebant, adeo ut mecum ftatuam, fl inuftio quendam, circa fanationem podagra?, producat effedlum, illud non evenire per aliquam mox^e propriam qualitatem, fed tantum per inu- ftionem ipfam, & fl golfypio inuftionem faceremus, nos tantum effedturos quantum moxa.
Ulterius mox^j goflypii & lanofitatis caf- tanese sequalem fumfi quantitatem, quam juxta fe invicem pofita combufli, comperique quodvis ho- rum trium poftfe reliquifle materiam aliquam olea- ginofam, fed moxa plurimam ; caufam imaginabar, quod, quamvis quantitas moxx quoad oculmn non major, revera plus materiae eflet in moxa, utpote qua? fubtilior molliorque, goflypio ardtius con- jundtas habere t partes, & propterea majorem olei quantitatem poll combufli on em reliquerat. Adeo ut credam dominum BiflchofF a Chinenfibus moxa? qualitates, praeparationemque extollentibus, efle fedudium ac deceptum. E t i a m
74 Of the Fibres of the Mufcles , &c.
Etiam animo recolens commune chirurgorum di&um,gofiypium (ut Holl. dicitur) efifeignitum, hoc eft, inflammationem caufare, & noxam afferre vulneribus, quando iis colligandis applicator. Ma- lignitatem, goffypio adfcriptam, in hoc confiftere judico, vi%. quod, ut antea didlum, duo plana, & per confequens qusevis particula, duo acuta habeat latera. Hasc acuta latera tenuiora, fubtiliora & duriora globulis fibrarumcarnis, propterea ( cum gofifypium vulneribus applicatur) non tantum caro adhuc fana, fed materia incarnationi novse infer- viens, & molliores came fana globulos habens, vulneratur ac lasditur imo condditur & refolvi- tur. Sed contrarimn cum linteo evenit, utpote cu» jus partes rotundas & ardte fibi invicem jundlas, majus corpus efficiunt, ideoque globulos carnis & materise incarnationi infervientis tam facile non, aut in totum non laedunt.
H je c font, nobilis vir, quas excellent!® veftras dominifque philofophis hac vice per 11- teras nunciare voiui : Submifle & fubnixe rogans, nobilitas veftra velit dominis philofophis mult am meo dicere nomine falutem, dataque occafione, refcripto, has bene perlatas, & quo padlo has me® obfervationes aut conveniant cum antecedent tibus, aut in quantum (fi) ab illis difcrepent, fig- nificare. Nunquam occafioni deero, qua demon- ftrare potero
ExcellentiJjime ClariJJime Vh\
Quod Sim Nobilitatis Vefirre Addict ijjimus Cult or ^
Subfignaverat
Anthonius Lewenhoeck.
( 75 )
Dr. John Cartel Letter to Dr. Hook, Worms like Millepedes, in the Stomach &c.
SIR ,
send you the following Cafe, which, in fome of its Circumftances, is not very common : A Girl about eight Years old, who has never been very healthful, but of late hath looked more pale than ordinary, and troubled with Pain at her Sto¬ mach, yefterday, upon taking a purging Powder, vomited a Sort of Infedts, to the Number of a- bout a Hundred, very much refembling little Mil¬ lepedes , I faw fome of them, and three, that were ! living, I put in a Box, and a little Duft to them,
, but they followed the Fate of the reft, and died i prefently j I have fent you fix of them. The Child had taken Worm-Seed over Night, but had a very troublefome Night, could fcarce be held a Bed, complaining both of the Pain and Sorenefs I: of her Belly, fancying the Worms had eaten it thin in one Place, and would eat a Hole in it. The Length of one of the biggeft, (though there was but little Difference) was * of an Inch : I view'd them through a fmall Microfcope, which did not reprefent them fo clearly, as to diftinguifh them from the common Wood-Lice, only their Bellies were more tranfparent, and their Heads of a more confufed Figure, which laft 1 thought afterwards might be caufed by the rowing up of the Ante mice or Horns, which I obferved fome of the common Millepedes to do, when they die. That among them which was black, was acciden¬ tally fo, by dropping a little Ink upon it.
The Child, after her vomiting, had a Stool, in which were feveral very fmall white Worms, about an Inch long, which are not uncommon, but
fhews
J
j6 Worms like Millepedes in the Stomach, 8cc.
fhews that the prim# <z abounded with fuch putrid Humours, as are ufually productive of a verminous Brood : She is now very hearty, and eats her Meat well, and free from all the former Symptoms.
I h a v e heard fome Stories of the like Nature, but am not forwards to relate them, becaufe they totally depend on the Credit of others : One Man I know, who, many Years ago, was reduced to a thin confumptive Habit, and, upon taking Mer- curius Dulcis , voided by Stool an incredible Num¬ ber, or rather Quantity, of fmall Animals, which (according to the Defcription I had of them) were iefs than thefe, and of a rounder Figure.
If thefe were bred in a Folli cuius of their own, that Part muft apoftemate, and fo a purulent Mat¬ ter be evacuated with them ; but 1 rather think, they muft be generated in the common Paffage, and I remember I have often feen Abundance of Animals bred in humane Excrements, but was not fo curious to obferve their Figure.
I t is hard to imagine, how Worms fhould live in the Stomach, amidft that acid Humour, which, whether it be the Caufe or Effect of Di- geftion, has the Force of a Menftriuim ; but it muft be fuppofed, that in fuch Bodies, the Fer¬ ment is alter’d, if not deftroy’d : You obferve lately, that Birds are very induftrious to kill In¬ fects before they eat them ; I am apt to think, if they pafs’d immediately into the Gizard, there was no Need of killing them firft • but the In - gluvies fupplying the Want of Teeth, and only macerating what other Creatures chew, has no A- cidity that would offend them.
S I R,
A Letter from Mr. j. Yonge, Sec. 77
Sir, I write this Account haftily, hecaufe I would have you fee them as foon as might be.
j
Manchefter3 I am^
Augufi 2 s, SIR,
1682.
Tour humble Servant ,
J. Cart e,
N. B. The Child had not taken any Millepedes, nor ufes to eat Earth or Dirt , which I have known fome difiemperd Children do .
: A Letter from Mr. J. Y o n g e, to cDi\ Hoo k, of divers curious Matters ob~ ferv’d by him.
Woman, about 36 Years old, had from her Childhood been fickly, more efpecially tor¬ mented in her Belly with a Pain, accompanied at firft, every three Months, and afterward every three Weeks, with a round Swelling like her Fifi, in her left Hypocondria , fenfibiy moving to and fro5, and plainly to be felt : Horrid Pain would then deprive her of Senfes, twelve or twenty-four Hours j and then fie would recover again, be without Pain, and the Tumour vanifh, without being followed by any Evacuation, of either Wind, Water, Excrement, &c.
Those Paroxyfms, for many Years, kept a due Courfe of three Weeks j {he was generally coftive, found that Milk irritated her Pain, that Flefh and all fait Meats difagreed with her.
N o T
f
78 ^ Letter from Mr . j; Y o n g e,
Notwithstanding this, fhe married about twelve Years fince, and had one Child. During her Breeding, her Pains obferv’d the Courfe, and abated nothing of theirVehemence, which equalled, if not exceeded that of Child-birth.
Under this Plague fhe liv'd, till about Fe¬ bruary , 1680, the Pain feem’d fix’d on the left Side, on the Region of the Spleen, and feem’d as if proceeded from the Lodging of fome heavy Thing, and begot fuch Pain, as fhe could not lie down in her Bed. Thus fhe continued in a miferable Con¬ dition, ufing Purges, Clyfters, &c. which were ad- vifed by charitable People, fhe being very poor.. The 15th of November , 1681, fhe became quit of all the Pain in her Side, and then felt fomewhat to burthen, and, as it were, flop the Intefiinum ReFkum , caufmg frequent Motions to Stool, but no Evacuation, but a little Slime like a Tetiefmus. The Suppreflion of her Evacuations that Way, for fix Days, fo prefs’d on fome of the urinary Chan¬ nels, that her Urine alfo flopp’d. In this doleful Condition, fhe fent for me, when, giving me the abovefaid Hiflory, I guefs’d fomewhat extraordi¬ nary muft be in the Reffum. Accordingly, exa¬ mining by a Probe, I felt a hard Subftance like a Stone, which, with a flrong pair of Forceps , I extracted, and then cleanfed out the Bowels with a Clyfter ^ fhe remained void of any Pain, and is fo to this Day.
The Thing extracted, was of a round Figure, fomewhat oblong, with fome Depreflions, fuch as a Man’s Fingers make on Pitch, Plaiiler, or Wax. In Weight, was one Ounce and a Quarter ; was five Inches round, fwram on W ater, though feem’d a Stone. Its Outfide was black as Jet, fmooth as V arnifh, but no thicker than a Man’s Skin j next to it, it was flony, or gritty, like Brick, the Thick- nefs of half a Crown. After fome Months, I
cut
to cDr. Hook, 8cc. yp
icut it in two with a Hatchet, and found that next
the gritty Shell, it was full of a woolly, hard I Subftance, like rotten Rags , or Sponge or : chew’d brown Paper, within which, lay a Lump of the Bignefs and Form of a fmall Prune. Cutting that in two alfo, 1 found it a Prune, or Plum in¬ deed, the Pulp of which was dry, and hard as Pafte-
board, as was the Kernel in the Shell, that lav in the Middle of it. 5 7 m
WhENCE it s manifeft, that all thefo Accidents that had fo long molefted this poor Woman, pro¬ ceeded from this Plum, or Prune, fwallowed above thirty Years before ; which, probably, ftuck in feme folding of a Gut, or a Cavern, or Cell of the Co¬ lon , increafing its Dimenfions by the Adhefion of new Matter, till (no one knoweth how) it tumbled down to the Refium , and 1 drew it forth. But how the Surface became petrify’d, and fo uneven, and
varnilh d over with a black fmooth Matter is to me a Wonder. 5 J
Before I broke it, I thought it might fo- a Gall-Stone, (tho’ foe never had the Jaundice) having lately feen a Gentlewoman, almoft dead in that Difeafe relieved by the Evacuation of one almoft as big as a Pullet’s Egg, and another from a Man, as big as a Nutmeg. Both followed Abo’ rollive before) with a Lask, difeharging prodigious Quantities of Choler. The Authors are innume¬ rable, that mention this latter Sort, though I meet none fo great, Vide La. Riverius Obf. at Henrico Ritffeo com. obf. 4. Tho. Bartholin Acta Med. A. 7 j *72. obf. 100. f . Fe melius lib. 6. de part. Mcrb & Sympt. J, Skenckms , Obf. Med. Sennertus , Sc But few fpeak of any, that appear generated in’ the Guts? Vide MijceL Curio fa voi 6. obf 20.
T II £ K £
8o to 'Dr. Hook, &c.
There lately died, in Cornwall , a Woman 6t" about 154 Years of Age 3 1 have employ’d a Friend to give me a particular Account of her Manner of living, &c. which 1 will not fail to tranfmit to your Hands.
Here was lately, alfo, ah Ewe kill'd, that had a full grown Lamb lapp’d up in the Omentum , a- mong the Guts, without the Womb j queftionlefs it was a Conception in tuba Fallopiana , which, when growing big, broke forth into the Bowels. But that the Pe dun cuius fhould hold, and where the Placenta was fattened, is ftrange : In the fun¬ dus uteri , it cou’d not be, and if any where elfe, how was the nutritious Juices, conveyed to it. It was feparated from the Uterus , and the Bowels thrown away before I knew it, fo that I could not make that Examination : This Accident is not fo new, but that Inftances of the like are given by Monf. Bayle , Mr. Blegny , de Graeff. \ Elfchotius , Riolanus , Rheynhufe , &c.
AChild was lately heard, by feveral People, to cry in its Mother’s Womb, fome Days before the Birth ; do not Children then breathe by the Lungs, before they are born?
I find fiuch another Relation ( if not the fame J of a Lamb in the Omentum, told by Mr. Younge, in the Phil. Tranf. Numb. 323.
Will I AM DERHAMj
0 bfervata qutfdam Anatomic a in Vefper- tilione diffefyto 22 die Sept. 1682. ‘Per T* Molyneux, M. 2). Dublinij.
EXternam hujus animalis hguram verbis defcribere, fupervacaneum fore exiflimavi, Utpote cum in hifce noftris regionibus adeo fre- quens occurrat Vefpertiiio, ut cuique volenti, eum vivum intueri, faciliime obtigit • vel faltem omni¬ bus conceditur, ut illius vjvam afpiciant delinea- tionem, cum apud tot varios autores de ani- malibus fcribentes, hoc accurate depidfum inve¬ nire liceat. lis igitur omnibus dmiffis, quss alii de Quadrupede hoc volanti jamdudum tradiderunt, folummodo hie notabimus qusedam hadlenus neg- iedta & inobfervata quse in illius diffedtione nobis videre contigit.
Et primo Penis in confpe&um venit, infignis quidem magnitudinis, habito refpe&ui ad exiguum animalis corpufculum ; in eo Oiliculum hujus figure (I.) acmulum delituit, oiliculum in Mu- rino pene contentum longitudine duplo fuperans.
f feftictilos habuit fatis amplos, extra abdominis ^cavitatem prominentes.
Veficulft Semin ales , ex utroque latere Veficae Uri~» \nari<& fitae, femine mirum in modum turgidse con- fpiciuntur, Ehafeoli magnitudinem sequantes.
Longitudo omnium Inteftinorum , fcilicet i a Pyloro ufque ad anum vixdum 6. pollices sequa- ibat ^ at in Mure diile&o (cujus fimilitudinem ex I omni animalium genere maxime prae fe fert.) Inte~ ^ftinorum circuitus 21 pollices fuperavit, nulla lhabita ratione illius appendicis inteftinum Ccecum ;ididtse5 quo omnino caret Vefpertilio ; cujus In- Itellinorum brevitatem, notabilem levitatis gratia^ a Natura conftitutam eile opinor, quae ab hoc Quadrupede, per aerem volitare deftinato, quic- uid eilet oneri provide defumpfit.
§2 Obfervata quadam Anatomic a
Ventri cuius , Lien & Renes iifdem partibus in Mure omnino perfimiles funt j at Hepar & Pul- mones in duos duntaxat lotos dividuntur.
Penitus mortuo animale Cor motum fuum, viz. Syftolen & Diaftolen., amplius horae fpatio peragebat.
Genii infigni convexitate donantur - eos autem in hunc finem ita fabricatos fufpicor, fei licet ut in tenebris videant • quippe per foiam nodlem & opa- ca crepufcula praedam fuam (Mufcas fcil) animal hoc infe&atur, quas inter volandum Hirundinis ad inftar captat.
Blafius in fua Anatome diverforum animalium, ubi de Vefpertilione loquitur, hanc controverfiam inter quofdam Medicos natam, meminit • fcil. an Caudam habeat ; fed de re ipfis fenfibus adeo evi- denti ortam die contentionem magnopere admiror, quippe seque bene difputaftent, an Mus Caudam habeat, cum in eo non magis manifeftam ojjis Coc~ cygis pfodufiionem (quae in omni animale Cauda nominatur) quam in Vefpertilione afpicere liceat.
Animal eft Viviparum , & nihil commune ullae Volucrum fpeciei poffidet, exceptis alts & robore Mufculorum pefftoralium alas moventium 5 quippe nec Bipes eft, nec Pennatum, nec Roftra« turn, &c. ficut omnia volantium genera : quamo- brem a ClariJJhno IVillughheo , in fuo pereleganti librode Avibus, inter Aves nequaquam numeratur, licet alii fcriptores Vefpertilionem inter eos collo- care haud dubitaverint.
D u m in vivis diet animal, in Pixide lignea in- carceratum per fpatium quatuordecem dierum af- fervabam,quo tempore Mufcos ex omni genere & Araneas avide comedebat : * Corporis autem Si-
, tus
*=**=»— wnMTmwaiinwi 11 fc 1 jega*^jggae^.oiaaaBeiff' i * i—n -rfaw — * t* —
* I have fee n him in this Pofhtre afleep, above forty fever d Times.
In Vefpcrtilione dijfecto. 0 ?
tus (quem Temper eligebat quoties fomnum cape- ret) fingulare quid & infolitum videtur • quippe fpreto molli gramine in fundo fuse Cave® Tub- ftrato, pixidis lateri adhsereret, & pofterioribus fuis partibus direcfte elevatis, anterioribus autem & Capite perpendiculariter deorfum pofitis, fuf- penfus Temper quiefceret: in hac autem infolita poiitura corpus Tuum fuftentaret pofierionim pedum :beneficio, quorum uterque quinque digitis, acu- tiffimis unguibus armatis, inftrucftus eft, & ab his lignese pixidis lateri infixis, pondus totius Corporis tuto dependebat 5 anteriores autem pedes, unicd tantum digito inftrudi, ad illius fuftentationem in hoc litu nequaquam contulerunt.
S i quis hujus animalis Oftiologiam cupiat, con- fulat Cap, 26. Partis Secundse Anatomise Blafianse variorum Animalium, & Tabulam 41. ubi Vef- pertilionis Sceleton & Effigiem videre licet.
,
■4
( h )
The Rule of Falfe Fojition , in Dec. 1682.
Ultiply the Pofition by the alternate Errors, and if the Errors be of the fame Kind, divide the Difference of the Produds, by the Difference of the Er¬ rors 5 but if they be of divers Kinds, the Sum, by the Sum: And the Quotient, fhall give the Number fought.
For Demonftration, what Number is that, whichbe- ing multiply’d by B 3 will produce the Plane B A 30.
Portions. Portions.
Let it be A — C — 6 Let it be A— D— 8
into B ~ B A — B C <— 18 into B=BA — B D := 24
A = 10.
B = 3.
C r=: 4.
D — 2.
BA — 30.
The Errors there ore are.
Firft Error. B A plane — B A *4* B C = 12.
Second Error. BA plane — BA -f B D = 6.
The Lefs fubftraded out of the Greater, there remains,
B C — B D zz: 6 the Difference of the Errors.
Which being multiply’d into their altern Errors, the Pro-
duds will be as follows.
BC Defed BD Defed
A — D A ■ _ C
gC'A-BCD' 96 BDA — BCD— ^
And Subftradion a- 7 _ BCA — BDA _ 60 __
gain being made J A ^TC^BD*^ ~~ 6 ~~1Q
c B
Again. Data < r> A . «
i Hil nuatntur A.
Sit A— C Sit A — D
in B = B A — B c. in B = B A — BD
B A pi. B A H- B q minus. BA pi. — BA + BD
Ergo Errores -f B C „ _|_ B D
A-D A—
BCA— BCD min. BDA+BDC
V*
B C A — B D A
Pof.
\
BC-BD
Of Falfe Toft ion.
Pof. A 4- B Pof. A + C > I) Errors E
B . C : % D . E .
CDz:BC.
ad + cd-aeh-be
AD — AE ^AD-AE _A D — A E_ .
D — E
As the Difference of the Errors to the firft Er¬ ror, fo is the Difference of the Portions to a Num¬ ber, which, contrary to the Sign of the firft Error, being added or fubftradted to or from the firft Pq«
Ilfition, gives the true Pofition.
When the Errors have different Signs, their Sum is their Difference,
The Reafon of the Proportion betwixt the two
I Errors of Pofition, is, becaufe the Numbers added or fubftradted, and apply Jd to the one Term of Proportion are proportionate to the Numbers added or fubftrafted; and apply'd to the other Term, becaufe two Numbers, apply'd or divided by the fame Number, continue the fame Propor¬ tion. Likewife, if you add orfubftradf like propor¬ tional Parts5 the Sums or Differences will be in fthe fame Proportion.
A s the Error of the firft Pofition to the Error the fecond Pofition, fo is the Error of the firft
I Operation, to the Error of the fecond Operation. But the Retftangle of the Means, is equal to :he Redfangle of the Extreams. Subftradt the Dne, from a Number containing the other, and j^ou leave the true ; only in greater Products con*« rain'd fo many Times, as the Difference of the lefler Error of Operation is to the greater Error of O- aeration, becaufe the lefter Error could not take
G 3 ^ay
8 6 Of Falfe CP of it ion.
way fo many Truths as the greater Error had made in the greater Product.
From B 4 From B A
Take BA— BC Take BA-BD_
Remains BA- BA + BC Remains BA— B AA B IF
The Difference B C D_B
~~qT ’
A— D BC
B C A— BCD Sub draft EDA — BCD Remains the Diff B C A — B D A Divide it by — .. . „ BC — BD
A BD
B DA— BCD
Is the true Pofition ( fought J
Dr*
\
cDr. Hook of Earths , Salts, &c.
M a r c h, 14, i 68}.
H E Nature of Clays, Stones, Limes, Sc.
A being difcourfed, 1 mention’d the Sorts of Stone which were here call’d Freefbone, viz. fuch as could be faw’d with a tooth’d Saw, fuch as Cone, Rigate , Burford , Ketten , Sc. That Stones were of two Natures, one bituminous, or ful- phureous, the other faline and watery ; the ful- phureous would calcine into Lime, the faline make Glafs, vitrify or diffolve, and moulder with the Rain, Air, and Froft. That both thefe Sorts are often found in the fame Portland-Stone one Part whereof will moulder, the other harden with the Air. That Loam is a Mixture of various Sorts of Clays and Sands, and may be feparated by waffl¬ ing. That fuch a Material is ufually chofen for Brick-Earth, as being moil eafily foftened and tam¬ per’d for moulding, and moil eafily and fpeedily dry’d for burning, and moll eafily burnt ; to make it yet more eafy for burning, tis ufually dry, and ex- pofedto the Winter Rains and Frofts, for mellow¬ ing againft the Spring. That the finefl Clay would make the bell Bricks, were it not for the more than ordinary Labour and Charge in wafh- ing, working, moulding, drying, baking, as is evident in Pottery, and Tiles, and efpecially in the Roman Bricks, which are fome of them of fo fine an Earth, fo well moulded, and fo tho¬ roughly burnt, as to lall even to this Day, as in¬ tire and perfedl as when firll made, in all proba- lility. That hungry Clay was hardeil and bell to endure the Fire without melting, but faline, and fine Clays,were molt apt to vitrify : And thence the throwing in of three or four Shovels of Salt into
Q 4 &
88 Of Earthy Salts , 5cc*
a Fot Furnace when hot, made all the Pots in the- Furnace to be glaz'd. That China was fueh ar| Earth, as was very difficult to be vitrify'd.
Concerning Salts, and other volatile and fix’d Bodies, I mention'd, that there were two Sorts, one that was homogenous to the Air, and v ould be diftolved into it. T his was call'd V olatile 5 the other heterogeneous, and would not at all be fo difTblved and mixed with it; and thefe were call'd Fixed. Of the Volatile, there are various Sorts, which will be difTolv’d into the Air, by dif¬ fering Degrees of Heat. Spirit of Wine, orfuch other fermented Spirits, Camphire, the odorous Gums of Flowers, and Herbs, will be difTolv'd into the Air with a fmall Degree of Heat; other Bodies more difficultly, and require a ftronger and ftronger Heat, as they are more and more fixed ; fo fome Salts and Gums, &c. will not rife at all : And thefe are call'd fixed Bodies, or Alcaly Salts. Of thefe which are difTolv'd into the Air, fome are. tailed as it were, by the Nofe, others not in the fame Manner as in Tindtures made in Waters ; fome, whereof the Tongue does tafle, others not.
Concerning the Oxford Trial by blue Starch, which they affirm'd would turn red, with Acids, I faid 'twas impoffible, Smalt being Glafs, but it mufl be Litmus , or Indico : But moil like¬ ly L itnius ; being a clear, blueTindlure ; but /;/« dico^ a thick Frecipitation.
T h e Experiment was very confiderable, though plain, giving a further Explanation of Gravity, by making a large Glafs vibrate, with a Viol Bow : By whichVibration, a certain Undulation is plainly feen to dart out from all fuch Places where the Glafs vibrates. And it was very plainly vifible, that the Water, and Bodies in it, did move towards every Inch vibrating Part, and from every other Part that was at reft.
Dr,
( §9 )
2)r. Hoc kAt Experiments of the floating of Eea^ &c. July 4, 1683.*
Wednesday, June 27, 16833 1 fhew’d two Experiments to the Society, which fuo ceeded, of which I gave an Account., Wednefday , July 43 16833 as follows.
Of the floating of unmelted Metaf upon the fame melted , with the Caufe.
I. There was melted, in a Crucible, about a j Pound and half of Sheet Lead, and whilft it re- J main’d melted, feveral fmall Pieces of the fame Lead were gently one by one, by the Help of a Forceps , laid upon the clear and bright Surface thereof (the Scum and Litharge being firft re¬ moved) and it was found that they all fwam upon it, and did not fink to the Bottom j but if they were all cover’d or plung’d under the Surface, they would not rife again, but fink to the Bottom, and foon be melted.
The Occafion of the Experiment, was a Sug- geftion, that Lead, when it concreted, did (as Wa¬ ter when it congeals to Ice.) fettle itfelf into a more rarify’d Texture, than when fluid j by which Means, it became lighter than the melted Lead, and fo fwam at the Top of it. But though the Effedt : 3 were anfwerable to the Aflertion, yet the Caufe, !ja% n’d, was falfe , for it was very evident, that :ithe Reafon of its fwimming, was much the fame with that of the fwimming of a Needle, or of Water-Spiders, and many other Infedts upon the 1 Surface of the Water j namely, a Coherence of the 1 Air to the Surface of the fwimming Body j which l Coherence of the Air does deprefs and remove a ; greater Part of the Fluid, Lead, or Water, than
the
90 Of the Floating of Lead, , &c.
the mecr Bulk of the Body itfelf would do ; which, in both thefe Cafes, is very evident • and was, in thefe T rials, very remarkable j for the Surface of the Lead did plainly bend and fink below its Le¬ vel, with a Roundnefs where the Piece of Lead lay $ which bending of the Surface, was made the greater by a thin Plate, or Skin of Li¬ tharge . which the Air does prefently make upon melted Lead, fo foon as ever a former is remov’d or fcummed off!
Of the Con den fat ion of Air by Water .
II. T here was Buck into the Side of a Piece of wooden Pipe, for conveying Water, a fmall cylindrical Pipe of Glafs, about a Foot long, and fomewhat better than half an Inch in Diameter , one End of which Pipe was hermetically feal’d, but the other End was opeiy and communicated with the Cavity of the wooden Pipe, by means of a fmall Hole bor’d in the Side of that wooden Pipe^ into which the open End of the Glafs Pipe wa:S thruft hard, having a little Linnen Rag wrapped about it, as is ufual for Taps put into the End of a Barrel, or other Veffel. Then ( there being about a Foot of Air left in the Glafs PipeJ Water was forc’d into the wooden Pipe by a fmall Force- Pump j and it was plainly to be feen, that as the Water was more and more ftrongly forc’d into the wooden Pipe, the Air left in the Glafs Pipe, by the Water that enter’d into it by the aforefaid Hole, was condenfed into aleffer and Idler Room , fo that hereby, the true Degree of the PrefTure of the Water could be eafily found and meafured* which was conceiv’d to be an Experiment, or !n- ftrument of great L ie for W ater- Works, becaufejby means hereof, the Force of Water, in any Pipe, might prefently be known ^ namely, both from
what
Two Experiments , /hewing. , &c# 91
what Height it defcended, and to what Height it would there again rife. The Rule of doing which, was the next Day, to be brought in.
2>. Ho 01 two Experiments , jhewing the Treffure of Water in Eipes , and how to Me afire it. Alfo the Exp anfi 'on of melted Metals , made before the Royal Society, July 4, 1683.
f It ' | -
'' r . ' ■ • -
JUl y the 4th, 1683. I read the Accounts of the two Experiments made June 27 , and likewife further explain'd the Ufes of them, by Difcourfes in other Particulars, namely, that the fecond Experiment was of great Ufe for the trying the Strength of Pipes, for Conveyance of Water. By which Means, I have examined feveral Sorts of earthen and other Pipes and Gements, and have found that earthen Pipes, made of a Material only, as hard as Houfe-Tiles, would endure the Preffureof 100 Foot of Water ; that the Ufe of the other Experiment, was chiefly luciferous, namely, to fhew the Nature of Fluids and Con- gruity, of which I fhould fhortly have Occafion to difcourfe more at large.
Then I produced and read the Pode, accord¬ ing to which the Prefliire of the W ater, in any Pipe, might, by means of a Trial with the former Inftrument, be calculated and reduced to certain Meafure in Feet and Inches. The Means of per¬ forming,! fhew5d, were principally two, firft Arith¬ metically, and fecondly, Mechanically,
The Arithmetical Rule was this ; that the Length of the Cylinder of the Air in the Pipe, be¬ fore it was prefs’d upon by the Water in the Pipe, Ihould be compared to the Length of the Cylinder 1 of
T wo Experiments Jhewing
of the fame Air, when comprefsM by the Water of the Pipe, and the Difference noted 5 namely, the Length of the Cylinder of Water thruft into the Pipe, by the Prefliire. Then to refolve this Proportion. As the Length of the Cylinder of W ater thus comprefs'd, is to the Length of the Cylinder of Water fo thruft in, fo the Height of the Standard of Water, at the Time of Trial, to the Height of the Cylinder of Water prefling in the Pipe, which is equal to the Height to which the Water of that Pipe, fo prefs’d, will afcend above the Surface of the Water in the fmall Pipe.
The Height of the Standard of Water, at the Time of Trial, is eafily known by the Height of the Mercurial Standard at that Time j which, be¬ ing now grown very common and ufeful, is almoft every where to be met with, and may otherwife be eafily fupply’d ; for as the Weight of Water, to the Weight of Quickfilver, fo the Mercurial Standard, to the Height of the Water Standard.
The Weight of Water, to that of Mercury , is by many Trials found to be near as 1000 to 13593? or as 1 to 15, according to his Account following Numb. - - - -
The
the Trejfure of Water .
T h e Geometrical or Mechanical Way3 was this. Upon a Table3 or Plane
is draw a Line3 as BAG j then crofs it at I i Right Angles^ with another Right Line, as D A E5 then divide A B3 into thirty-fix PartSj and continue the fame Divifion5 from A towards C, fo far as you have Occafion of i Foot Heights of Preflure ; as fuppofe to ioo 5
then
94 Two Experiments Jhewing
then fubdivide one of thefe Parts, lying next to A into twelve equal Parts. Then knowing the prefent Water Standard, count, from A towards B, fo many Parts and Duodecimals, as it is then Feet and Inches : Crofs the Line, at that Point at Right Angles, with another Line, as G H, and from G, fet off the Length of the Cylinder of Air in your Glafs, before Compreilion , then fet off the Length of the additional Cylinder of Water, from A to¬ wards D, as fuppofe to £, and laying a Rule o« ver the Points H and F, fee where it crofieth the Line A C, as at I, then count the Parts and Duo¬ decimals from A, and that fhall give the Preffure or additional Fleight of the Water, above the Le¬ vel of the Water in your Water Poifer in Feet and Inches : The Reafon of all which depends upon the reciprocal Proportion of the Strengths of Air to the Extenfions thereof.
The fecond Experiment, was made, to fhew a Way, how to find the true and comparative Expan¬ fion of any Metal, when melted, and fo to com¬ pare it both with the Expanfion of the fame Metal, when folid, and likewife with the Expanfion of any other, either fluid or folid Body. An accu¬ rate Account of which is necellary, to compleat a Hiftory of Expanfion or Gravitation. The Me¬ thod of trying it was, by having a Veffel full of melted Lead, and alfo a folid Body of Iron to be funk into it * this folid Piece of Iron was about i I Inch Cubical, and into it, was faflened a very {mail Wire of Iron, big enough to thruft it under the Surface of the melted Lead, and make it fink therein, (for, of it fe If, it fwaiii upon the Lead, as Wood upon Water). This W ire wasfaftened per¬ pendicularly, under a Scale, and fo much Weight put into the Scale as ferved to make it fink under the Surface of the Lead , then taking it out of the Lead, and feeing by the additional Weights, put
in
TheTrejJure of Water, 95*
into the other Scale, to counterpoife it, firft in the Air, then in Water, or any other Liquor, the comparative Weight of each of them was eafily dif- coverable.
The Reafon of the making of which Experi¬ ment was, to hint the Necefiity there is, in all Experiments fit to be made Ufe of for any Philofo- phical Theories, of reducing them to a Certainty of Quantity 3 without which, no certain and un- i queftionable Conclufion can be made. Now tho* a certain Standard of Weight, Meafure, Expan- fion, Power, Motion, &c. be not made Ufe of ; yet if fome one determinate Meafure for each of them be pitched upon, ’twill be enough to make the comparative Trials ufeful; though it were to -be wifh’d, that fome univerfal, natural Standard of Meafure for all Things were found out, thofe that have hitherto been thought of, having been C doubted of, as to their Universality and Certainty, at all Places and in all Times.
Not knowing when the following Experiments j were made , I infert them after the foregoing , by i reafon of fome Congruity between them .
W, Derh am>
( )
An Account of fotne Trials for the finding out the Trejfure of the Tarts of Water one upon another ; and the elafiical Tower of the Air .
FO R the making thefe Experiments, there was prepar’d a long Tube of Glafs, feal’d at one End, and being eredted perpendicu¬ larly, with the feafd End downwards, it was fill’d with Water, and fo faftened againlt the Side of a Wall 3 then there was taken another fmall Tube of Glafs, very even drawn, and fmall enough to be let down within the former Tube j this Tube was 12 Inches long, and was feal’d at one End, and divided into In¬ ches, Halfs, and Quarters 5 then, to the open End of this Tube, was hung a fmall, long Plummet of Lead, which would eafily flip down to the Bottom of the longer Tube, and draw down the fmall Pipe with it ^ both which were gently fo let down by a fmall Thread, as the Experiment requir’d, which afforded thefe Ob- fervations. The Pipe, when the lower and open End firft touch’d the Water, being full with Air, not heated by the touching the Pipe with a warm Hand, or otherwife, was ob- ferv’d by Degrees, as it defcended, to be in part fill’d with Water, and fo much the more by how much the deeper it defcended. And ob- ferving the Degrees of Condenfation of Air in the Pipe produced at feveral Depths, we found them to be thefe. At Grejham College, the 24 half Inches of Air loft one half Inch of its Extenfion
at
Experiments Jbe&ing, See. -97'
It 2 Half's at 3 Half's at 4 Haifs
at which is therefore d 5th Part of a Cy¬
linder of Water able to counter-balance the Pref- fure of the Air. The whole therefore may hypo¬ thetically be judg’d to be -
1 did, fince that, ereeft a Tube fome 1 3 Foot high 5 and fitting all Things as in the former Ex¬ periment, I collected this Table A, whofe firft Row ofNlimbersfliewstheequal Spaces into which the Air was extended , and the laft Ihews the Height of the Water above A the under Surface of the Air. Since that, in the fame Tube Handing ill the fame Place, I reiterated the Experi-
48
47
46
45
44
43
00 0 Si-
17
27
36;
45"
|
24 |
06 |
42 |
5 8; |
|
23 |
IT |
41 |
68* |
|
22 |
31 |
40 |
SO |
|
21 |
52 |
39 |
9 if |
|
20 |
76t |
38 |
I05;- |
|
19 |
IOlT |
37 |
1 17 |
|
l8 *7* |
142 |
36 |
*3°! |
ment, and collected this following Table B.
All which three Tables, being fo diffe¬ rent one from another, may feem to overthrow each other, and the Cer¬ tainty of this Kind of Experiment in general.
But as I cannot vindi¬ cate the Trials from fome Errors (it being almoft impoffible to make thefe Kind of Trials fo accurate, there fhall be no Miftake committed ) fo neither do I believe, that thefe feeming Contrarieties do wholly proceed from the Unaccuratenefs in the Procefs. For fince the Air is fometimes under a greater, and fometimes a lefs Preffure, the Degree’s of Force, requifite to promote the Condenfation further, muft necefiarily be differing.
And hence by the firft Table, I judge the Height of a Cylinder of Water, able to' balance the Pfeffufe Of the Air, when that Experiment was
H
that
98 Experiments Jhewing
made to be by the Second Experiment
I judge the counter-balancing Pillar, then to be between 390 and 400 Inches, or near about 33 Foot ; by the third, I guefs it to be about 382 Inches, or near about 32 Foot. This Experi¬ ment therefore, if accurately made, at feveral Sea- fons and Times of the Year, may afford us a very eafy Way of knowing the Preflure of the Air at that Time, and this more accurately and nicely, than can be perform’d with Mercury the ordinary Way. For whereas the Shortening and In- creafe of the Mercurial Cylinder, is at mod not above 2 or 3 Inches, in this Experiment, the aque¬ ous Cylinder will change fourteen times as much.
Next, this Experiment may help us to guefs at the Preflure of the Sea Water againft >he Air, let down to the Bottom of it in a diving Engine, by knowing the Proportion between the Gravity of fait and frefh Water. But it were very de¬ finable thatfuch,as have the Opportunity of making Trials at Sea, would be diligent in it. For though there feems to be no Doubt, but that Water pro- portionably preffeth according to its perpendicular Fleight j yet it is not eafy to predidf, how much it may vary from that Hypothefis j which Devi¬ ation may be caufed, either from the extreme Cold at the Bottom of the Sea, which may weaken the Spring of the Air, or from the differing Gra¬ vity of the upper and lower Parts of fait Water j or fromfomewhat elfe, whereof we may be yet ig¬ norant. Now for the more accurate making of thefe Trials, I think it were very requifite to have fome fuch Engine as this.
Take a good ftrong Glafs Bottle, that will hold about a Gallon ; and let there be fitted to it a handfome Screw Cover of Brafs, and fhap’dl ike thofe Covers that are ufually put upon Chirurgeons Bottles, that are made of Pewter. Let the Cover
be
The Treffure of Water. 99
fee very well cemented on, and the Screw be made j to go veryclofe through the Top of this Cover j ! let there be made feveral very fmall Holes with a i Needle Drill, then hang a good Weight under the I Bottle, and let it down with this Cover up- 1 moft, for by this Means, by drawing it up from • ! feveral Depths, and weighing the Quantities of 1 Water it brings up, it will be eafy to know the 1 Weight of the incumbent Column of Water.
There might be fnany other 1 Ways, but this, I take to be the : moft cheap, eafy, and certain of 1 any ; not is there any Danger of breaking the Bottle, , either inward : or outward , for as the Bottle de- ; fcends, the Water rufhes in, and as it is drawn up, the Air goes out.
The following Experiments are here inferred^ fry i reafon of their Qongruity with the foregoing.
Whuam Durham*
- • ■■ - 5
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• ~ I , ? ^ . | , t j / 1 ' • *■ • Jf ■
H % Mon
( ICO )
More Experiments of Trejfure ,
THere was taken a Glafs Tube A B C, {Fig. I.)
about 23 Inches long, and near \ of an Inch over $ this was clofe feal’d up at one End A, and the other End B was drawn into a very fmall Pipe C, and bended according to the Shape in the Fi-
x 2
gure. This Pipe was found to weigh f 4gr*
or 874 Grains, being fill’d with fait Water, and the Outfide wiped dry (which was conftantly done in all the fubfequent Trials) it weighed
4^1 -J- io}r* or 2140 Grains, whence if wededudt
the Weight of the Pipe 8 74, we have 1266 Grains for the W eight of the W ater that fill’d the Pipe. T his Glafs Tube being faften’d to a Line, to the End of which was hang’d a Plummet of Lead, to make it fink j ’twas fitted fo as to be let down perpen¬ dicularly into the Water with the feal’d End A foremoil:, by which Means the fmall Hole of the Pipe C was open downwards (that Hole being made purpofely fmall, that the Air could not get out at it whilft the Water got in, nor the Water get in whilft the Air was palling out.) Then the Glafs was, for aihort Time, fo held in the Water, that all of it, except the fmall bended Pipe, was cover’d and inclos’d with the Water (which wasa
ob—
Experiments jhewing. , &c. roi
obferv’d in every Trial, to the End that the Ain within the Pipe, might be well cooled) and be¬ ing let down to the Bottom, and there fuffer’d to ftay for a fhort Space. Afterwards being drawn up3 loofened - from the Line, dried, and exadlly
weighed ; its Weight was found 3-— ? -f S Grains
or 1833 Grains j whence, deducing the Weight of the Tube 874, we have 959 Grains for the 'Weight of the Water it brought up. The Place iwas in the Channel to the North of Q uinborough , ithe Depth of the Water 16 Fathom and a Foot, or 97 Foot, where we made the fubfequent Tri¬ als which are rang’d in this Table.
I
1 Top full At 97 Foot deep * — 2 At 97 Ft. deep — 2 At 8 Ft. 3 In. — 2 Ft. At 16 Ft. 6 In. — 2 Ft. At 33 Ft. — 2 Ft.
At 66 Ft.
At 66 1
At 33 C From the Mouth At i6*f of the Tube
At 8* )
2140 — 874= 1266 1833 — 874 = 959. 307 1832 — 874 = 958. 308
1060 - *874 — 186. 1080
1257 — 874= 383. 883 1500 — 874= 626 . 64O 1737 ““874 — 863. 403
l734—874 “860. 406 1530 - 874—656. 6lO
1296—874—422. 844
1131 — 874 =257. 1009
I A B u n d l e of Corks being knit up in a Hand¬ kerchief, and fatten’d to the Line at 33 Foot from ihe fmall End of the Glafs, the Tube was again 1 et down to the fame Depth, and the Corks, float¬ ing upon the Water, fufpended it at that Depth t 'or, a good, while afterwards. Then drawing up the fcylinder,by meafuring, the Cylinder was found to nave taken in juft as much Water, as it had in the jaft Trial, but the Weight of the Glafs was not i examin’d. Other Trials were made the next Day J with the fame Glafs Cylinder, viz,
H 3
i-oz, Experiments Jbewing
At 81 Foot from the Top 1172 — 8 74“ 298. Juft at high Water, the Water being at a ftancl At 84 Foot 1131—874=257 At i6|Foot 1300 — 874 = 426 At 33 Foot 1510 — 874 = 636 At 49I Foot 1635 —874 — 761 At 66 Foot 1712 — 874=838
The Trials did agree, by Meafure, with fome I had made in the Morning.
ANOTHERTrial was made of the laft Experi¬ ment, becaufe it was done when the Water had fome Current, and the String feem’d to ftream a good Way from the Perpendicular ; to prevent which Inconvenience, the Boat was fuffer’d to drive with the Current, by which Means, the Line feem’d to go down perpendicularly into the W a- ter. So the Cane being pull’d up, after it had ftaid fome time at the Depth of 66 Foot, it weigh’d 1719 — 874 = 845. At 82^ Foot, and left to drive perpendicularly 1883 — 874== 1009,
Wedncfday, March the wth, in the After¬ noon, near the fame ^Place , where the former Trials were made , there were made thefe following Experiments of Compref fiotL
UN to the Neck, or Mouth, of a common Quart Glafs Bottle, was fitted a Valve, that opened inwards, and fhut outwards ; this Bottle: Was fo let down into the Water, that the Mouthi went foremoft, by which Means, the Water had,, as the Bottle was finking, a free Paflage into the
Bodj
The *P re (pure of Water. 103
Body of it, tocomprefs the Air j but by the fhutting of the Valve, when the Bottle was again drawn up, it was hinder’d from getting out. This Bottle, when empty, weigh’d 37 l Ounces, and 24 Grains, or 1 8204 Grains, fill’d with fait Water, it weigh’d 7 8-J Ounces and 3 Grains, or 37563 Grains , whence, taking the Weight of the Bottle 18204, we have 19359 Grains, for the Weight of the Water, that fill’d the Bottle. This Bottle being let down 13-r Fathoms by the Ship’s Plumb Line, or 81 Foot, r the Valve was fo hard fhut, when it was taken up
I again, that it was difficult to be thruft open. Though when the fmall End, or Mouth, of the Bottle, was fet upward, the Valve being made of 1 Brafs, without Leather, was found to leak a little, by the hiffing Noife the Air made at it. And when by a Knock, the Valve was beaten down, the Air j made a Noife in rufhing out like that of a Bottle of j Ale when it flies, the Bottle, and the Water it i brought up, weigh’d 65^ Ounces, or 31656 i Grains j whence, deducing the Weight of the j Bottle 18204, we have 13452 Grains for the Weight of the Water. This Bottle was again let down to the Depth of 14 Fathom, or 84 Foot » and, being drawn up, was found to weigh, whilft the comprefs’d Air remain’d in it, 65^ Ounces, and 19 Grains, or 31279 Grains j when the Air was let out, it loft 21 Grains of its former Weight, counter¬ poising only 31258 Grains, which was fuppos’d to proceed partly from the freeing of the comprefs’d Air, and partly from the Lofs of a little Water, that the violent Eruption of the Air had blown a- way j from which laft Sum, by deducting the Weight of the Bottle 18204, we have 13054 for the Weight of the Water.
H 4,
March
104 Experiments Jhewittg
March the 13 th, another Experiment was made with another Bottle of the fame Fafhion, which empty, weigh’d 3 7 \\ Ounces and 12 Grains, or 18162 Grains ; fi I’d with fait Water to the Valve, it weigh’d 77 H Ounces and 3 Grains, or 37353 Grains j whence, deducting the Weight of the Bottle 18162, we have 19191 the Weight of the Water that fill’d it ; this Bottle being let down 8 Fathom, or 48 Foot, the Bottle, comprefs’d Air, and Water together, weigh’d 60 \ * Ounces and 12 Grains, or 29142 Grains; the Air being let out foftly, which requir’d a long time, and the Bottle, and Water afterwards weigh’d, was found 24 Grains lighter, viz. 29118 Grains ; whence, deduc¬ ing the Bottle 18162, we have 10956 Grains for the Water. The Experiments are ranged together jn this Table.
The Bottle, with a bended Copper Pipe at the Top, being let down 8* Foot deep, brought up in it 4TI Ounces, and 24 Grains of Water, the Bottle being weigh’d before-hand with a dead Weight, or counterpois’d ;the fame Bottle, kept longer at the fame Depth, brought up Sh Ounces and 25 Grains of Water , tfie fame Bottle, kept yet longer a great deal, brought up 9^ Ounces and 6 Grains ? the Water that fill’d the Bottle, weigh’d 41 H Ounces and 24 Grains , which different Pro¬ portions of Water, taken in, we judg’d to proceed, either from the leaking of the VefTel at the Screw, by which Means, the Water had a Paflage into the Bottle below the Mouth of the bended Pipe, which would therefore ferve for a Vent-hole for the Air to get out at ; or elfe that the Motion of the Top of the Water being a little uneven, the Prefiitre upon the Bottle mull confequently alter, there being fometimes a greater, fometimes a fhorter Pillar of the Water above it , fecondly, the Bottle itfelf was, by the cockling of the Boat,
f o me-
The Trejfure of Water . ioy
Comet imes lifted higher, then deprefs’d lower, which did alfo alter the Height of the prefling Pil- ! lar , whence, as the PrefTure was a little increas’d, the Water got in s and, as it decreas’d, the Air ! got out $ and, being held a long while in that Pofture, many of thofe Changes did very much i augment the Quantity of Water within the Glafs.
Experiments of the Weight of Water,
A white Glafs Viol, made in the Manner defcrib’d in Figure II. with a fmall fhort Neck, was, by Trial, round to weigh, when empty, 1425 '! Grains ; when fill’d exactly full with fait Water, it weigh’d 5247 Grains , whence, deducting the 1 Bottle 1425, we have 3822 Grains, the Weight i of the fait Water. The fame fill’d with frefh i1 Water taken out of the Thames at Greenwich , a- bout low Water, weigh’d 5164; whence, de- [ dueling 1425, we have 3739, the Weight of that : frefh Water. And weighing afterwards the Wa- : ter, wherewith the Strong Ale at Margat is brew’d, i1 we found it exactly the fame with the Water :l taken up at Greenwich ♦ whence we conclude, the I Proportion of thefe frefh Waters, to this fait, to ; be as 3 7 3 9 to 3 822 j that is, near as 45 to 46.
T 'rials of the Heat and Cold of the Water .
A seal’d Thermometer was let down to the [ Bottom of the Water, at 16 Fathom and a Foot, with the great Ball upwards, and the Stem down- 1 ward, to the End that, if the Cold were extreme, it might have fo far condenfed the Spirit of Wine, as to have admitted the Air to have got in out of the Neck. And fo by pulling it to the Top, we might have known the Cold at Bottom ; but i jtjiough the Thermometer was fuffer’d to remain
ic6 Experiments Jhewing,&cc.
a long Time at that Depth, and were fuddenly pull’d up, we could not find that it had any whit more condens’d the Spirit of Wine, than it was by. keeping the fame Thermometer a pretty while juft under the Water, at the Top, when we judg'd the Temperature of this Water, both at the Top, in in the Middle, (for, by other Trials, we found the fame at other Depths) and at the Bottom, to be all the fame.
N. B. Ehe Inftrument defcriPd in the Nuntius ad Abyfliim, much better for the Purpofe than this ;
R. W,
Obfervations of Sound .
Being at a Place of the Eh ante s, about four Miles above Grave fend, there happen’d to be Ihot off feveral final 1 Pieces of Ordnance, by a Ship that was about half a Mile farther up the River j the Multitudes of the Echoes of each of which Shots, made a Noife among the feveral Hills, Woods, and Banks, on both Sides of us, juft like Thunder. And could they have been number’d, they would,queftionlefs,have exceeded an Hundred. And having fince had the Opportunity to obferve the Noife of Thunder, it feem’d to me to be dq^ ducible partly from Echoes 3, which would yetfeem more probable, if we could, by any Experiment, find that the Clouds would rebound or echo a Sound. A Gun being afterwards (hot off by the Veffel we were in, when we were near the Mouth of the Eh antes , and feveral Ships being on this and that Side of us, we could very fenfibly hear fe¬ veral Echoes rebounded from them.
( 10 7 )
\ J)ra Hook *s Contrivance of a very com¬ modious Windmill ; communicated to the Royal Society, July, n, 1683,
JUl y the nth, I read the preceding Difcourfe and Accounts of the two Experiments fhew’d on July the 4th ; and further explain’d each of them by verbal Difcourfes. Then I fhew’d thefe i two Experiments following, which I explain’d by Difcourfes, fpmewhat in the following Manner.
The Firft, was the Module of a Windmill, in which were thofe Particulars following confidera- ble, not to be found in any pther yet made ufe o£
1. That it had no Need of any Houfe, but what might be placed, either immediately upon the Ground, or under the Ground, according to the feveral Ufes to which it might be apply’d. Whence follow’d,
2. That the Houfe need not be any Impedi¬ ment to the Force of the Wind, which it ufually is in all other Windmills.
3. That it doth of itfelf turn to all Winds, and fo needs not the Attendance, Watching, and Labour of Men to fet it, which is neceffary in o~ ther Mills.
4. That the Vanes are contriv’d of the moft perfect Form, to receive the whole Power of the; Wind, for the Cylinder thereof it is expofed to : Which is effected by the particular Slope of the Vanes thereof, whereby the Force of the Wind becomes equal upon every Part of the Vane, from the Center to the Tip, or Extremity thereof An equal Progreflion of Wind caufmg every Point of the whole Vane to make an equal Arch of Rota- I tion, or an equal Angle at the Axis.
5* F or
I
108 Of a Commodious Windmill, Sec.
+e?
5. For that it needeth not fo big an Axis, nor fo ftrong Vanes as other Mills, the greateft Strength of this being in the Way of pulling, the other in the Way of thrufting , and this being capable of being lengthen’d by Ropes, like the Tackling of a Ship.
6. F o r the eafy Way of producing a circular Motion below, without the Help of Trundles or Cog-wheels, which are both a great Impediment to its Motion, and do wear, and often need Repair.
7. For the eafy Way of communicating a re¬ ciprocating perpendicular Motion, which is ufually perform’d by the Help of Wheels.
8. For the Cheapnefs of it, there being fo ma¬ ny Particulars not neceffary to this, omitted, which are ufually done in other Kinds, and not without Neceflity.
All which Particulars confider’d, it makes it to be the moft plain, fimpie, cheap, and eafy to be made and ufed, that has been yet made 3 and yet the moft powerful in its Effedh, and the moft univerfally applicable to all Purpofes ;(as grinding, bruifing, beating, fawing, pumping, placing, twifting, drawing, turning, lifting, that can be made of equal Bignefs.
I have thought worth while , toinfert this Account of the Windmill although fcarcely intelligible without Figures , or a Module , which I never could meet with ) becaufe Jon/ebody , or other , may be fo fortunate to find the Module , or, by the Hints here givetiy contrive a Windmill like this.
W. Der.ha m.
Dr,
( )
2)r. H o o k’j* Contrivance to flop great Weights failings July n, 1683.
.
1
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1
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!
t
\
■
TH E fecond Experiment was a very plain and eafy Way, how to ftay a Weight from falling, when the Rope, or Chain, by which it is drawn up or let down, fhall chance to break. This was effeded by afmall Arm extended out from the Top of the Weight to the Side, with a Hand, or Pipe, at the End thereof, which grafped, or in- clofed, another Rope or Chain, extended from the Top to the Bottom , which Hand, or Pipe, was fo wide, as to flip freely upon the faid Rope, fo long as the Weight was fufpended by its own Rope ^ but fo foon as that any way fail'd, the Hand grafped the Side Rope fall, and hinder’d the Weight from defending to the Bottom. This was one of the plainefl, eafieft, and moft Ample Ways of effeding this End, though the fame may be effeded divers other Ways, as certainly,which 1 have alfo con¬ triv’d. The explicating it, by a Scheme, makes it the more intelligible. I reprefents the Weight, a b the Arm, moving with a Joint at c, upon the o- ther Part of it £, fafl: into the Weight, e/reprefents the Rope, by which the Weight is either drawn up or let down, fatten'd to the Elbow m ^ by which Means the Wrift, and Hand of the Arm, is kept at Right Angles with the Part fall in the Weight, and fo the Hand flips freely upon the greater Rope g hj extended from the Top to the Bottom, to which the Weight can defcend ; d reprefents a Spring, by
which.
\
2io Of Great Weights falling, <5cc«
"which, fo Toon as the Rope of the Weight, which holds by the Elbow c, fails, the Arm is extended Freight 5 by which the Hand £, prefentjy holds faft the Rope, or Chain G h, by being made ob¬ lique to the Perpendicular, and, fo creeking the Rope, and fo hinders it from falling , as, by the Experiment fhewn, plainly appear’d.
The Ufe of which Contrivance, though pof- fibly it might, to fome, feem very trivial and in- fignificant, as feeming to be calculated for keep¬ ing a Clock, or Chime Weight, from falling, is not altogether fo flight and foolifh , for even for that Ufe it may fome time or other poilibly fave 100 Pound Expence, and the Lives of fome Men. But if apply ’d, in general, for the hindering W eights to fall, it may deferve a fomewhat better Value, and be found very considerable, fince it may be very inftrumental to fave many Mens Lives, and much Charge, and great Inconveniences, which do very often now, for the Want thereof, happen. For whereas, in many Mines, the Men themfelves are often drawn up and let down in Buckets , and generally the Ores, Stones, Waters, and divers other Things, belonging to thofe Works neceflary for procuring Ores, or other Mi¬ nerals, are fo conveyed $ and upon the failing of the Rope, Chain, or other Part of the Engine, do often fall from Top to Bottom, and fo afe not only dafhed in Pieces themfelves, but deftroy, and do oftentimes irreparable Injury to Men, or what elfe they meet with in their Fall. By this Means, all fuch Bodies are fecured from the Fall, and kept hanging at the Place where they were when the Rope brake, or other Part of the Engine fail’d* and thereby the Bodies themfelves are preferv’d in¬ tire, and no other Harm done by their Fall. The fame Thing is applicable alfo to Men, afcending, or defcending, by Ropes or Rope-Ladders, and to Stones, l imber, or Materials for a high Building.
Dr v
( III )
*Dr. Hook5/ Way to take the ImpreJJlons of Medals , &c. imparted to the Royal So¬ ciety. Odtob, 31, 1683.
HAving been fhewn, by Mr. Frazier , the Imprellions of feveralofthe King of Frances I Medals, in a certain thin tranfparent Subftance, much like Mufcovy Glafs, but much more tough *
1 on which, on the one Side, appear’d the perfect lmpreflion of the Medal, in Entaglio , or funk in; and, on the oppofite Side, the very Figure of the faid Medal in Baffo Relievo , or fwelling out. And, r, confidering what Way this might be done, having ;j formerly taken off the Figure of certain Carvings, j by Glue, fo as to be able to caft them in Plaifter 1 of Paris , or burnt Alabafter; upon making Trial j with a Glue made of ItthuocoUa , diilblv’d over a a gentle Heat, in courfe Spirit of Wine, by lay- 1, ing it upon a fair ftamp’d Crown Piece, and fuf- i fering it to lie a confiderable Time, till it was tho~
C rough dry, cold, and hard j I found that it af¬ forded me the fame Kind of