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DUKE
UNIVERSITY I
LIBRARY I
treasure 'Room
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By the Council of the Royal Society of London for Improving of Natural Knowledge.
Ordered, That the Book.^ritten hy Robert Hooke, M. A. Fellow of this Society ^Entitled^ Micrographia, or fome Phyfiological Defcriptions of Minute Bodies, made by Magnifying GlalTes, with Obfervations and Inquiries thereupon, Be Frintedby John Martyn ^and Janies Alleftry, Printers to the faid Society^
Novem, 23, 1664*
Brolincker. P. R. S,
MICROGRAPHIA
e
e
O R S O M E
Phyfiologkd Defcriptions
MINUTE BODIES
made by
MAGNIFYING GLASSES
WITH
Observations and I n oja i r i e s thereupon*
By R. HO 0 KEj Fellow of the R o y a l Society.
lS!onpojJts ocnlo quantum contendere Linceus^
Non tamen idcirco contemn as Lippus inungi. Horat. Ep. Lib. i.
LONDON^ Printed for James Allejiry^ Printer to the Royal Society, and are to be fold at his Shop, at the Rofe and Crown in Duck: Lane. M DG LX V 1 1,
'1
a
Di^rtifed by the Internet Archive in 2016
https://archive.org/details/micrographiaorso1670hook
TO THE
SIB,
Do here moft: humbly lay this fmall Prefent at Tour Majejiies Royal feet. And though it comes accompa- -ny’d with two difadvantages, the meamefs of the Author, and of the Subjedi; yet in both I am incouraged by the greatnefs of your Mercy and your Knowledge. By the one\ am taught , that you can
A forgive
The Epistle
forgive the prefumpnom Ofeniors: And by the other^ chat you will not e- jleem the leaftwork of Nature^ or Art-, unworthy yom Oh fervation.Psxm^{k. the many felicities that have accompani’d your Majejlies happy Reftauration and Government-, it is none of the leaft confi- derable, that Philofofhy and Experimental Learning have projpefd u nder your Royal Patronage. And as the calm profpericy of your Reign has given ms xhe kifure to follow thefe Studies of quiet rc' tirement-, fo it is juft, that the Fruits of them ihould , by way of acknowledge' ^ be ^'return’d to your Maj^y. There are, ""Sir, fevcral other of your Subjeds, of your Royal Sockty-,^:mm bufie about Nobler matters : The J«- 'provemenl of ManufaBwes and- Agficul- Pure-, Intreafe oi Commerce -, theTt/- ioMdge sA Navigation: In alb which they dfe afsiJledhY your Majejlies Incou'
Lagphehi and Example, ” Amidft all thofe
■ greater
Dedicatory.
greater Defigns,! here prefume to bring in that which is more proportionable to the fmalnefs of my Abilities , and to offer fome of the leajl of all vifihk things^to that Mighty King^ that has efla- Uijhtan Empire over the heft of zlllnr vifihle things of this World, Minds of Men.
Tour Majejlies mo fl humble
' -r-'-
' , and mojl obedient SubjeB andServant'i
^ T/-
*
-f.j \u
OBERT ' H ooiCe.
£tlj» 'V' *’5'* '^fo
Oj*,> <{jK>
TO THE
ROYAL SOCIETY.
ter my Addrejl to our Great Founder and ?a- tron^ I could not but think my felf oblig'd ^ in confideration of' thofe many Ingagements you have laid upon me , to offer thefe my poor Labours to this MOST 1 L L LI- STRIOIIS ASSEMBLY. YOU have been pleas’d formerly to accept of thefe rude Draughts, I have fince added to them fome Defcriptions-, and fome Conjebiures of' my own. And therefore, together with YOUR Acceptance^ I mu\\: alfo beg YOUR pardon.The Rules YOU haveprefcrib d YOUR felves in YOUR Philofophical Progrefs do feem the beft that have ever yet been praftis’d. And particularly that of avoiding Dogmatizing , and the efpoufal of any Hypothefis not fufhciently grounded and confirm’d by Experiments. This way feems the moft excellent , and may preferve both Philofophy and Natural Hiftory fromits former Corruptions In faying which, I may feem to condemn my own Courfe in this Treatife ; in which there may perhaps be fome Expreffions^ which may feem morepofitive then YOUR Preferiptions will permit: And though I defire to have them underftood only as CorijePiures and Quaeries (which YOUR Method does not altogether difallow)yet if even in thofe I have exceeded, ’fir. fit that I fbould declare, that it was not done by YOUR Direftions. For it is moft unreafonable, that YOU fbould nn&cvgo l\it imputation the faults of my Con^ jefiures^ feeing YOU can receive fo [mail advantage of reputa- tion by the fleight Ohfervations of
TOVR moft humble and moft faithful Servant
ROBERT HOOKE.
1 7* k the great prerogative of Mankind above other Creatures^ that we are not only able to behold the works of Nature^ or barely our lives by them^ but we havealfo thefower of Gonfidering^ _ comparing, altering, affifting, arid improving
them to varioH6 ufes.And o5 this Is the peculiar priviledge of humane Nature in general^ fo Is it capable ofbeingfofdr advanced by the helps of Art^ and Experience, as to make fome Men excel others in their Obfervations, and I>eduhiions,almofl as much as they doBeafis. By the addition of fuch artificial I nftruments andmtt\\ods,there may be,in fome manner, a reparation made for the mifchiefs, and imperfeSiion, mankind has dr awn upon it felf by negligence,and intemperance, and a wilful and fuperjlitiotis deferting the P refer ipts and Rules of Nature, whereby every man,' both from a deriv'd corruption, innate and born with him, and from his breeding and converfe with men,is very fubjeH to flip into all forts of errors.
The only way which now remains for us to recover fome degree of thofe former perfebf ions, feems to be,by reVtifying the operations of the ■ Scnik,the Memory, and Re?i{6n,fince upon the evidence,the Rrength, the integrity, and the right correfpondence 0/ all thefe,all the light, by which our aVuons are to be guided, is to be renewed, and all our com- mand over things is to be eftablijht.
It is therefore moft worthy of our confideration, to recolleU their fe- fever al defeEis, that fo we may the better under fland how to fupply them, and by what affi fames we may inlarge their power, and fecure them in performing their particular duties.
As for the afiions of .Senfes, we cannot but obferve them to be in
a many
The Preface.
mart] particulars much outdone hy thofeof other Creatures^ and when at bejlpbe far Jhortof the perfection they feem capable of: And thefe infirmities of the Senfes arife from a double caufe^ either from theAxf- proporcion of the Objed to the Orgznyvhereby aninfinite number of things can never enter into them^or elfe from error in the Perception, that many things^ which come within their reach^ are not received in a right manner.
The Uh frailties are to be found in the Memory ; we often let many things flip away from us^ which deferve to be retain d ; and of thofe ' which we treafure up^ a great part k either frivolous or falle ; and if good^ and fuhfiantial^ either in trad of time obliterated, or at befi fo overwhelmed and buried under more frothy notions^ that when there k need of them^ they are in vain fought for.
The two main foundations being fo decehable^ it k no wonder^ that all the fucceedingworks which we build upon them^of arguing^ conclu- dingPefinirigfyudging^ and all the other degrees of Reafon^ are lyable to the fame imperfedion.) beings at befl^ either vain^ or uncertain : So that the errors of the underftanding are anfwerable to the two other ^ being defedive both in the quantity andgoodnefs of its kpowledge ; for the lU mits^ to which our tlmghts are confi ndr^ are fmall in refped of the vafi extent of Nature it felf ; fomepartsofit are too bicge to be comprehen- ded^ and fome too little to beperceived. And from thence it mufifoU lowy:hat not having a full fenfation of the Objed^ we mufl be very lame and imperfed in our conceptions about it , and in all thepropofitions which we build upon it ; hence, we often take the fhadow of things for the fubftance,y?w<j// appearances yor ^op^ limilitudcs, fimilicudes • for definitions; and even many cf thofe^ which we think, to be the moji folid definitions^ are rather exprejfions of our own mifguided apprehen- fions then of the true nature of the things thernfelves.
The ejfeds cf thefe imperfedions are mardfefiedin diferent ways^ac- cording to the temper anddijpofition of the fever al minds cfmen^ fome they incline togrols ignorance and fiupidity^ and others to a pre- fumptuous impofing on other mens Opinions^ and a confident dog- matizing on matter Sj whereof there k no ajfurance to be given.
The Preface.
Thm dll the uncertamtjy and miftak§s of humane aEtiom^ proceed either from the. narrownefiand mndring of our Senfes, from the flipper rinefi or delufim of our Memory, from the confinement or rajhnefi of o«rUnclerftanding,/o^/;^^ tk no wonder^ that our power over natu~. ral caufes and efeEis k fo flowlj improv dy feeing we are not only ^ to.. corAtnd with the obfcurity and ditficulEy of the things we work,
andthinkyhut even the forces of our own m\nd$ conlj^ire to betray ttSi 7hefe heir^ the dangers in the procefi of humane Reafony the remedies of them all can mly proceed from the real, the meehanical, the. c%r.. pcrimehtal Philofophyywhkh has thk advantage overthePhilofophy of difcourfe and diCpiwmonyhat whereas that chiefly aims at the fubtilty of its VeduEUons and Conclufions , without much regard to the firfl ground-work.y which ought to be well laid on the Senfe and Memory ; fo thk intends the right ordering of them alfand the making them fer^ viceable to each other,
Thefirft thing to be undertaken in thk weighty worky k a watcfir ftilnefs over the failings and an inlargement of the dominion, of the Senfes.
7o which end it k requifitCy firfty That there fimld be a fcrupu- lous choictyand a ftrifl examination, (fi the reality y conftancyy and certainty of the Particulars that we admit, 'Thk k the firfi rife where- m truth k to begWy and here the mofi fever Cy andmofi impartial dili- gencty mufi beimphyed ; the ftoring up of ally without any regard t6 eiddeuce or ufiy will only tend to darknefs and corfufton. We mufi not therefore efieem the riches of ourPhilofophicaltreafure by the num- ber mlyybut chiefly by the weight rnoft vulgar Inflanas are not to hneglePiedfiut above ally the m<fi inftruQive are to he entertain d% thefootfteps of Nature me to hetracdymt only in her ordinary courfc, hut when fibe fiems to be put to her filuftsyto make rmny doublings and tumkigs, and to ufe fame kind of art in indeavoufmg to avoid pur difcovery.
The neoct care to he takeny m refi^eht of the Sonfes^ k 4 fupplying.gf their infirmities with Inftruments, andy Os k werOy fhc adding ficial Organs to the natural ; thk in one of them has been op late years
dccom-
The Preface.
accompli fht with prodigious benefit to all forts of ufeful kpowledge , by the invention of Optical Glaffes. By the means of Telefcopes, there is nothing fo far diftant hut may he reprefentedto our view ; and- by the help o/Microfcopes, there is nothing fo fmall, cui to efcape our inqui- ry ; hence there is a new vifible World difcovered to the underftanding. By this means the Heavens are open and a vaft number of new Stars^ and new Motions^ and new ProduHtons appear in them^ to which all the antient Afironomerswere utterly Strangers. By this the Earth it felfi which lyes fo neer us^ under our feet^fibews quite a new thing to us^ and in every little particle of its matter we now behold almoft as great a variety of Creatures^ as we were able before to reckon up in the whole Univerfe it felf.
It feerns not irnprobahle , but that by thefe helps the fubtilty of the compofition of Bodies., the firuHure of their parts., the various texture of their matter., the infiruments and manner of their inward motions., and all the other poffible appearances of things., may come to be more fully difcovered ; all which the antient Peripateticks were content to comprehend in two general and Q unlefi further explain'd') vfelejl words of and Bovm. From whence there may arife many admi-
rable advantagespwards the increafe of the Operative, and the Me- chanick Knowledge, to which this Age feerns fo much inclined, becaufe we may perhaps be inabled to difcern all the fecret workings of Nature, almoft in the fame manner as we do thofe that are the produlcions of Art, and are managd by Wheels, and Engines, and Springs, that were devifed by humane Wit.
In this kind I here prefent to the World my imperfeHIndeavours ; which though they fh all prove no other way confiderable,yet, I hope, they may be in fome meafure ufeful to the main Befign of a reformation inPhilofophy,if it be only by fhewing, that there is not fo much requif d towards it,any ftrength qflrmgmmon,or exaHnefs ofUethod,or depth cf Conzevcvf[2it\on(though the addition of thefe,where they can be had, muft needs produce a much moreperfeU compofure)as a fincere Hand, and a faithful Eye, to examine, and to record, the things themfelves as they appear.
And
The P R E t A C E.
And I heg my Reader^ to let me take the holdnefi to affiire him^ that in thisprefent condition cf kriowledge^ a man fo qualified y 06.1 have indeavoured to he^ only with rejolutiori^ and integrity^ and plain intentions of imploying hvs Senfes arightymay venture to compare the re- alky and the ufefulnejl of his ferviceSy towards the true FUlofophy^ with thofe of other men^ that are of much JirongeCyand more acute fpecula- nonSythat fhall not make ufe cf the fame method by the Senfes.
The truth the Science of Nature has been already too long made only a work of the Brain and the Fancy ; It is now high time that it Jhould return to the plainnefi and (oundnefi of Obfervations on ma- terial and obvious things. It is faid of great Empires^ That the beft way to preferve them from decay^ is Co bring them back to the firft Principles, and Arts, on which they did begin. The fame is undoubtedly true in Fhilofophyythat by wandring far away into \nwi- Iihlt^oiionsfios almofi quite deftroy d it felfand it can never be re- cover ed^ or continuedy but by returning into the fame fenfible paths, in which it did at firfl proceed.
If therefore the Reader expeHs from me any infallible DeduHions^ or certainty of Axioms, / am to' fay for my felf that thofe Jironger W&rhof Wit and Imagination are above my weak Abilities \ or if they had not been foj I would not have made ufe of them in this pre^ fent SubjeH before me : Whereever he finds that I have ventur'd at any fmallConjeliureSy at the caufes of the things that I have obfervedy Ibefeech him to look upon them only as doubtful Problems,<i;2^ uncer- tain ghefe, and not as unquefiionable Conclufionsy or matters of un- corf utable Science ^ Ihave produced nothing her e^ with intent to bind his underftanding to an implicit confent ; I am fo far from that^ that I defirehimy not abfolutely to rely upon thefe Obfervations of my eyeSi if he finds them contradiHed by the future Ocular Experiments cf fi- ber and impartial Difcoverers.
As for my party Ihave obtained my endy if thefe my fmall Labours fhall he thought fit to take up fime place in the large flock of natural Obfervations, which fo many hands are bufie in providing. If Ihave contributed the meaneft foundations whereon others may raife nobler
b Super-
The Preface.
Superftrudlures, lam abundantly fati^fied ; and all my ambition that I may ferve to the great Philojophers cf thk Age , 06 the and the grinders of my Glaffes did tome ; that I may prepare and fur^ niji) them with fome Materials, which they may afterwards order and manage with better skill-, and to far greater advantage.
The next remedies in thk univerfal cure of the Mind are to be ap- plyedto the Memory, and they are to confifi of fuchDirehiions as may inform m., what things are bejl to be ftor’d up for our purpofe., and which is the beft way cf fo difpofing them.^ that they may not only be kept in Mciy.^but ready and convenient .yo be at any time iproduc'd for ufe., 06 occafion Jhall require. But I will not here prevent my felf in what I may fay in another Bifcourfe , wherein I Jhall make an aU tempt to propofe fome Confederations cf the manner of compiling a Na^ tural and Artificial Hiftory., and of fo ranging and regiftring its Particulars into Philofophical Tables., as may make them rnofi ufful for the raifeng cf Axioms and Theories.
The laft indeed is the mofe hazardous Enterprize., and yet the mojl ncceflary ; and that is., to tak^ ftuch care that the J udgmenc and the Reafon of Man J which is the third Faculty to be repairdand im^ prcrud ) Jhould receive fuch affejlance., as to avoid the dangers to which it is by nature mofe feubjehU, The ImperfebUons, which I have al- ready mention'd., to which it is lyable., do either belongto the extent, or the goodnefs of its knowledge ; and here the difficulty is thegrea^ ter., leaf that which may be thought a remedy for the one Jhould prove deftrudive to the other., leaft by feekjng to inlarge our Enow- ledge., we Jhould render it weak, and uncertain ; and leaft by being too fcrupulous and exaSi about every Circumftance of tty we Jhould confine and ftreighten it too much.
In boththefe the middle wayes are to be takeny nothing is to be omitted, and yet every thing to paft a mature deliberation ; No Intelligence from Men cf all ProfejfeonSy and quarters cf the Worlds to be flighted, all to be fo feverely examin’d, there remain no room for doubt or inftability ; much rigour in admittingy much ftridncfs in comparingyand above ally much flownefs in debatingy and
fhynels
The Preface.
fhynefs i;z determinings kto be gra^ifed. The Underftanding ^ order all the inferiour fervices of the loprer Faculties; hut yet it kto do thk only as a lawful Mafter, and not as a Tyrant. Itmuji not in- croach upon their Ofices^ nor take upon it [elf the employments which belong to either of them. It muftw?x.di the irregularities of the Sen-- fess but it mufi not go before them^ or prevent their information. It mufi examine, range, and difpofe of the bank, which k laid up in the Memory ; but it mufi be fure to makedii^tin^ion between the fobcr and well colledled heap , and the extravagant Idea’s, and miftaken Images , which there it may fometimes light upon. So many are the WnkssUpon which the true P hilofophy depends, of whichsf anyone be loofe,^ or weak , the whole chain k in danger of being diffolvd ; it k to be- gin with the Hands and Eyes, and to proceed on through the Memory ^ to be continued by the Reafon ; nor k it to fiop there^ but to come about to the Hands and Eyes agahs and fo, by a continual palTage round from one F acuity to another ^ it kto be maintained in life and firengthy as much as the body of man kby t/je circulation of the blood through the fever alparts of the body^ the Arms^ the Fat, the Lungs^ the Hearts (^tid the Head.
If once thk method were followed with diligence and attentions there k nothing that lyes within the power of human Wit (or which k far more efeHual ) of human Indufiry , which we might not compafi ; we might not only hope for Inventions to equalize thofe of Copernicus, Galileo, Gilbert Har vy, and of otherSs whofe Names are almofi tofis that were the Inventors ^Gun-powder, Seamans Compafs, Printing, Etching, Graving, Microfeopes, &c. but wMltitudes that may far exceed them : for even thofe difeoveries feem to have been the products of fome fuch me- ihodsthough butimperfeU ; What may not be therefore expeHed from it if thoroughly profecuted? Talking contention of Atgxivotnx.2, would foon beturridinto labours ; all the fine&rt^ms of OpinionSs and um- verfal metaphyfical natures, which the luxury of fiubtil Brains has de- vis dy would quickly vanifljs and giveplace to folid Hiftories, Experi- ments and Nocks. And as at firfis mankind Ml grafting of the forbidden Tree of KnowledgCsfo w, their Pofieritys may be inpart reftor*d
by
The Preface.
by the fame rvay^ not only by beholding and contemplating, but by ta- iling too thofe fruits of Natural knowledge^ that were never yet forbidden^
From hence the World may be ajftfled with variety of Inventions^ new matter for Sciences may be colleded, the old improv’d, and their rufi: rubb'd away ; and as it k by the benefit of Senfes that we receive all our Skill in the works of Nature fio they alfo may be wonderfully benefited by tty and may he guided to an eafter and more exabi performance of their Offices ; 'tk not unlikely-i but that we may find out wherein our Senjes are deficierrt^ and as eafily find wayes of repairing them.
The Indeavours of Skilful men have been mofl converfant about the affiftance cf the Eye^ and many noble VroduFiions have followed upon it ; and from hence we may conclude^ that there k a way open'd for advancing the operations^ not only of all the other Senfes fiut even of the Eye it felfiyhat which has been already done ought not to content usfiut rather to incourage m to proceed further^ and to attempt greater things in the fame and diffe^ rent wayes.
‘Tk not unlikely^ but that there may be yet invented feveral other helps for the eye^as much exceeding thofe already found^as thofe do the bare eyefuch as by which we may perhaps be able to difcover living Creatures in the Moon^ or other Planets^ the figures of the compounding Particles (f matter^ and the particular Schcmatifms andFtxtwvts of Bodies.
And as GlaflTes have highly promoted our feeing, yo "tk notimproba^ blefiutthat there may be found 7/zdfwji Mechanical Inventions to improve our other Senfes^ cf hearing, fmelling, tailing, touching. 'Tknot impojfible to hear a wKifyer a furlongs diftance^ it having been already done ; and perhaps the nature of the thing would not make it moreim-> poffible., though that furlong jhould be ten times multiply d. And though fome famous Authors have affirm'd it impojfible to hear through the x\\m~ nell plate of Mulcovy-glafs ; yet Ikjiow a wayfby which tkeafie enough to hear one fpeak. through a wall a yard thick. It has not been yet thoroughly examindfiow far Otocoullicons may be improv'd.^ nor what other wayes then may be of quickning our hearing., or conveying found through ocher bodies then the A\r: for that that k not the only medium,
I can affure the Reader .,that I havefiy the, help of a diftended mvcrpropa-
The Preface.
gated the found to a very confiderabte difiance in an inftant, or with as feeminglj quick, u motion as that of lights at kafi^ incomparably fwifter thenthat^ which at the fame time was propagated through the Air ; and this not only in a firaight line ^ or direbr^ hut in one bended in many angles.
Nor are the other three foperfehl^ but that diligence, atcention, and many mechanical contrivances, may alfa highly improve them. For fince the fenfe of fmelling feems to be made by the fwife paflage of the Air ( impregnated with the fieams and effluvia of feveral odorous Bodies') through the grifiy mt^Lnders of the Nofe whofe furfaces are cover’d with a very fenfible nerve , and moiftned by a tranfuda- tion from the proceflus mamillares of the Brain , and fome ad- joyning glandules, and by the moifi fteam of the Lungs, with a Liquor convenient for the reception of thofe effluvia and by the adhefion and mixing (f thofe fieams with that liquor ^and thereby afebiing the nerve,, or perhaps by infmuating themfelves into the juices of the brain,, after the fame manner,, as I have in the following Obfervations intimated,, the parts of Salt topafi through the skins of Efs,, and Frogs, SincCi I fay,, fmelling feems to be made by fome fuch way,, 'tis not improbable,, but that fome con- trivance,, for making a great quantity of Airpafi quicKthroughthe Nofe, might O'i much promote the fenfe of fmelling,, as the any wayeshindringthat pajfage does dull and defiroyit. Several try ah I have made,, both cf hindring and promoting this fenfe^and have fucceeded in fome accordingto expebiation ; and indeed to me it feems capable of being improv'd,, for th6 judging cf the confiitutions of many Bodies, Perhaps we may thereby alfo ’-judge {as other Creatures feem to do) what is wholfomeyvhat poyfon ; and in a word, what are the ffecifick. properties cf Bodies,
There may be alfo fome other mechanical wayes found out , of fenfibly perceiving the effluvia of Bodies ; feveral Infiances of which,, were it here proper, I could give of Mineral fieams and exhalations ; and it feems not impoffible, but that by fome fuch wayes improved, maybe difeovered, what Minerals lyeburied under the Earth, without the troubk 'to dig for them ; fome things to confirm this Conjebiure may be found in Agricola, and other Writers of Minerals, fteakjngcf the Vegetables that a re apt to thrive, or pine, in thofe fieams, f Whether
. The P R E F A C E.
Whether alfothofe fleams^ which feem ta ijfue out of the Earthy and mix with the Air ( and fo to precipitate fome aqueous Exhalations^where- with *tk impregnated ) may not be by fome way detebded before they produce the efe^^feems hard to determine ; yet fomething of thk kind I am able to difcoverdy an Injlrument I contriv'd to fbew all the minute variations in the pr e/fur e of the Air ; by which Iconfiantly find^that before , and during the time of rainy weather^ theprefure of the Air is lefi^ and in dry wea- ther , but efpecially when an Eaftern Wind ( which having pafl over vaft trails of Land k heavy with Earthy Particles ) blows^ it k much more^ though thefe changes are varied according to veiy odd Laws,
The Infirument is this. I prepare a pretty capaceous Eolt-head A B, with a fmall ftcm about two foot and a half long D C 5 upon the end of this D I put on a Ifnall bended GlalsjOr brazen Syphon D E F ( open at D, E and F, but to be doled with cement at F and E, as occalion ferves) whole ftemF fhould be about fix or eight inches long, but the bore of it not above half an inch diameterjand very even 5 thefe I fix very ftrongly together by the help of very hard Cement , and then fit the whole Glafs A B C D E F into a long Board,or Frame, in fuch manner,that almoft half the head A B may lye buri- ed in a concave Hemifphere cut into the Board R S ^ then I place it lb on the Board RS, as is expreft in the firfi: Figure of thefirft Scheme ^ and fix it very firm and fteady in that pofture, fo as that the weight of the Mercury that is afterwards to be put into it,may not in the leaf!: fhake or ftir it ^ then drawing a line X Y on the Frame R T, fo that it may divide the ball into two equal parts, or that it may pafs, as ’twere, through the center of the ball. 1 begin from that, and divide all the reft of the Board towards LIT into inches, and the inches between the 2 5 and the end E (which need not be above two or three and thirty inches diftant from the line X Y) I fubdivide into Decimals 5 then flopping the end F with loft Cement,orlbft Wax, I in- vert the Frame, placing the head downwards, and the Orifice E upwards ^ and by it, with a fmall Funnel, I fillthewholeGlalswith Qiiickfilver, then by flopping the fmall Orifice E with my finger, I oftentimes cred: and invert the whole Glafs and Frame,and thereby free the Quickfilver and Glals from all the bubbles or parcels of lurking Air ^ then inverting it as before,! fill it top full with clear and wellftraind Quickfilver, and having made ready a fmall ball of pretty hard Cement, by heat made very foft, I prels it into the hole E, and thereby flop it very faff 5 and to fecure this Cement from flying out afterward,! bind over it a piece of Leather, that is Ipread over in the in- fide with Cement, and wound about it whilft: the Cement is hot : Having thus faftned it, 1 gently ereft again the Glals after this manner : ! firft: let the Frame down edge-wayes, till the edge R V touch the Floor, or ly horizon- tal 3 and then in that edging pofture raife the end R S 3 this ! do ,. that if there chance to be any Air hidden in the final! Pipe E, it may alcend into the Pipe F, and not into the Pipe D C : Having thus ereded it, and hung it by the hole Q, or fixt it perpendicularly by any other means, I open the end F,
and
The Preface.
and by z{m2i\\Syfhen I draw out the Mercury fo longjtill I find the furfaee of it AB in the head to touch exactly the line X at which time I immedi- ateiy take away the Syphon , and if by chance it be run fomewhat below the line X Y, by pburing in gently a little Mercury at F, I raife it again to its defired height , by this contrivance I make all the fenlible rifing and fal- ling of the Mercury to be vifible in the furfaee of the Mercury in the Pipe and Icarceany in the head A B. But becaufe there really is feme (mall change of the upper forface allb, I find by fevei al Oblervationshow much it rifes in the Ball, and falls in the Pipe F, to make the dift ance between the awo lurfaces an inch greater then it was before ^ and the meafure that it falls in the Pipe is the length of the inch by which I am to mark the parts of the Tube F, or the Board on which it lyes, into inches and Decimals : Ha- ving thus jufined and divided it, I have a large Wheel M N O P, whole outmolHimb is divided into two hundred.equal parts , this by certain fmall Pillars is fixt on the Frame RT, in the manner exprell: in the Figure. In the middle of this, on the back fide, in a convenient frame, is placed a fmall Cylinder, whofe circumference is equal to twice the length of one of thole divilionsj which I find anfwertoan inch of alcent, or defeent, of Mercury : This Cylinder I, is movable on a very fmall Needle , on the end of which is fixt a very light Index K L, all which are fo pois’d on the Axis, or Needle, that no part is heavier then another : Then about this Cylinder is wound a fmall Clew of Silk, with two Imallfteel Bullets at each end of it G H^ one of thefe, which is fomev/hat the heavier, ought to be fo big, as freely to move to and fro in the Pipe F ^ by means of which contrivance , every the lead: variation of the height of the Mercury will be made exceeding vifible by the motion to and fro of the fmall Index K L.
But thk pihutone way of difeovering the effluvia of the ' Earth mixt with the Air ; there may be perhaps many othersyvitnejl the Hygrofeope^ an Inftrument whereby the watery fleams volatile in the Air are difeerned^ which the Nofe it felf vs not able to find, 7hvs I have deferib'd in the following Trahi in the Befeription of the Beard of a wild Oat. Others there are^ay be difeovered both by the Nofe , and by other wayes alfo. 7hu6 thefmo?k of burning Wood k fmelt, feen, and fuffickntly felt by the eyes: 7he fumes of burning Brimffone are fmelt and difeovered dfo by the deflroying the Colours of Bodies , as by the whitening of a red Rofe ; And who knows^ but that the Induflry of man^ following thk me- thodynay find out wayes of improving thk fenfe to as great a degree of per ^ fedfton as it k in any Animaf and perhaps yet higher.
'7k not improbable alfofiut that our rafte may be very much improv'd., either by preparing our tafl for the Body., as., after eating bitter things., Wme.,or other Vinous liquors, are more fenfibly tafled ; or elfeby pre- paring
The Preface,
paring Bodies for our taft ; as the dijfolving of Metals with acid Liquors^ make them taftable^ which were bfore altogether infifid ; thu6 Lead be- comes fweetcr then Sugar ^ and'SWNtr more bitter then Gall^ Copper andiron ofmofl loathfome tofts. And indeed the buftneft of this fenfe being to difcover the prefence of diffolved Bodies in Liquors put on the Tongue^or in general to difcover that a fluid body has fome folid body diffolvd in iL and what they are ; whatever contrivance makes this difcovery improves this fenfe. In this kqnd the mixtures of Chymical Liquors af- ford many Inftances ; as the fweet Vinegar that is impregnated with Lead may be difcovered to he fo by the affufion of a little of an Alcalizate folution ; 7he bitter liquor 0/ Aqua fbrtis and Silver rnay be difcover d to be chargd with that Metals by laying in it fome plates of Copper : ^Tts not improbable alfoJ)ut there maybe multitudes of other wayes of difco- vering the parts diffolvd^ or difjoluble in liquors ; and what is this difco- very but a kind of lecundary tafting.
’7m not improbable alfof)ut that the fenfe of feeling may be highly im- provd^ for that being a fenfe that judges of the more grofs and robuft motions of the Particles of Bodies, feems capable of being improvd and ajfijied very many wayes. Thus for the diftinguifhing o/Heat and Cold^he Weather-glafs Thermometer, which Ihavedefcrib din this follow- ing Treatife., do exceedingly perfeSi it ; by each of which the leaft varia- tions of heat or cold., which the moft Acute fenfe is not able to diftinguifh.,are manifefted This is oftentimes further promoted alfo by the help of Burn- !ng-glaiIes,^J«J the lik^.,which colleH and unite the radiating heat. Thus the roughnefs and fmoothnefs of a Body Is made much more fenfible by the help of a Microfcope, thenby the moft tender and delicate Hand. Perhaps., a Phyfitian might., by fever al other tz.r\g\h\Q proprieties, difcover the conftitution of a Body as well as by the Pulfe. I do but inftancein thefey.0 fbew whatpojfibility there may be of many others., and what proba- bility and hopes there were of finding them^f this method were followed ; for the Offices of the five Senfes being to deteH either the fubtil and curi- ous Motionspropagated through all pellucid or perfectly homogeneous Bodies; Or the more grok vibrative Pulfe communicated through the Air and all other convenient mediums, fluid or folid : Or the
effluvia
The Preface.
effluvia of Bodm diffblv’d in the Air ; Or the particles of ho£es diP folv’d or diflbluble in Liquors, or the more quick and violent king motion 0/ heat in all or cf ihefe: whatfoever does ar^mjesfro^ mote artj of tbefe kinds of criteria, does afford a of improving fomi onefenfe. And what a multitude cf thefe would a diligent Man meet within his inquiries ? Andthk for the helping and promoting the fenii* tive faculty on^»
Next^as for the Memory, or retentive faculty, we maybe fufficienty' inflrubied from the written Hiffories of civil adHons, what great afft-^ fiance may be afforded the Memory^ in the committing to writing things ob- fervable in natural operations. If a Fhyfitian be therefore accounted the more able in his Faculty^ becaufe he has had long experience and praHice, the remembrance of which^ though perhaps very imperfeU^ does regulate alt his after aHions : What ought to be thought of that man^ that has not only a perfect regifter of his own experience j)ut is grown old with the experience cf many hundreds of years^ and many thoufands of meri.
And though of late , men^ beginning to be fenfible of this convetitence^ haue here and there reglfired and printed fome few Centuries, yet for the mofipart they are fet down very lamely and imperfebUy^ and^ I fear ^ many times not fo truly ^ they feeming^ fever al of them^ to be defigridmore for Oftentation publique ufe .* Forgiot toinfiancepthat they do for the mofipartpornitthofe Experiences they have made ^ wherein their Patients have mifearriedft is very eafie to beperceiv d^hat they do all along hyper- bolically ektol their own Preferiptions^ and vilifie thofe of others. Not-
withfianding all which ^ thefe kinds of Hifiortes are generally efieem'd ufe- ful^ even to the ablefi Fhyfitian,
What may not be expelled from the rational or dedudf i\^c Faculty that is furnfht with fuchM^tetidls^ and thofe fo readily ndzpted^ and rangd for ufepthat in a moment^ ^ ^twere^ thoufands of Jnfiances^ ferving for the illufrration,determination, or invention, of almofi any inquiry^ reprefented even to the fight ? Howneer the nature of Axioms mufi all thofe Propoff cions which are examindb fore fo many nefles ? And how difficult will it be for any^ though never fo fiubtil an er- ror in Philofophy^ to feape from being difeovefd^ after it has indufdthe touchy and fo many other d - What
The Preface.
What kind of mechanic alwaj^ andphjfical invention alfo m there re- quird^that might not thi^ way be found out ? The Invention of a way to find the Longitude of places k eafily perform'd^ and that to 06 great per- fection 06 16 defifd^ or to 06 great an acciiratenefs 06 the Latitude cf places can be found at Sea ; and perhaps yet alfo to a greater certainty then that has been hitherto founds as I flj all very Jfeedily freely manifefi to the world. The way 0/ dying in the Air feems principally unprabUcable^ by reafon of the want of ftrength in humane mufcles ; if therefore that could be fuppli dfit werej think.-) eafie to make twenty contrivancesto perform the office of 'N mgs : What Attempts alfo I have made for the [applying that Defeoi^ and my fucceffes therein^ which^ Ithink.^ are wholly new ^and not inconfiderable^ I Jh all in another place relate.
^Ti6 not unlikely alfo., but that Chymifts, iffthey followed thus method., might find out their fo much fought for Alkaheft. What an univerfal • Menftruum , which diffolves all forts of Sulphureous Bodies, lhave difcover'd ( which has not been before taken notice of as juch ) lhave Jhewn in the ftxteenth Obfervation.
What a prodigiou6 variety of Inventions in Anatomy has this latter Age afforded., even in our own Bodies fn the very Heart, by which we live, andtheBvdmyvhich is the feat of our knowledge of other things ? witnejl allthe excellent Works of Pecquet, Bartholinus, Billius, and many others ; and at home,ofDobiorU2irvy,Do5ior Rnt,Dobfor Wi\l\s,DoSior Gliflbn. //^Celeftial Obfervations we have far exceeded all the An- tients,even the Chaldeans and Egyptians thernfelves, whofe vail: Plains, high Towers,^^W clear Air, did not give them fo great advantages over us, as we have over them by our Glades. By the help of which, they have been very much outdone by the famous Galileo, Hevelius, Zulichem ; and our own Countrymen, Mr. Rook, Boldor Wren, and the great Orna- ment of our Church and Naticn,the Lord Eilhop of Exeter. And to fay no more in Aerial Difeoveries, there has been a wonderful progref made by the Noble Engine of the moft Illuftrious Mr. Boy\t,whom it becomes me to mention with all honour:^ not only as my particular Fatron,but as the Patron of Philofophy it felf ; which he every day increafes by his La- bours, and adorns by his Example.
The
The P P. E F A C E.
The good fuecejl of all thefe great Men^and many others^ and thi feemingly great obvioufneis of mofi of their and divert other Inventions^ which from the beginning of the world have been^ as \were^ trodon^ and yet not minded till thefe lafi mquifidve Ages ( an Argument that there may be yet'behind multitudes of the like ') puts me in mind to recommend fuch Studies^and the profecution of them by fuch methods^ to the Gentlemen of our Nationyrhofe \d\{\xrc makes them fit to undertake, and the plenty of their fortunes to accomplilh, extraordinary things in this way. And I do not onlypropofe this kind of Experimental Philofophy as a matter of high rapture and delight of the mind^ but even as a material and fenfi- ble Pleafure. So vaji is the variety of Objefls which will come under their InfpeViions., fo many different wayes there are of kindling them., fo great is the fatisfaflion-o/ finding out new things, that I dare compare the contentment which they will injoy.,notonlytothatcf contemplation, but even to that which mofi men prefer of the very Senfes themfelves.
And if they will pleafe to tak^ any incoUragement from fo mean and fo imperfect endeavours as mine., upon my own experience., I can afure them.,without arrogance., That there has not been any inquiry or Pro- blem in Mechanicks, that I have hitherto propounded to my felf but by a certain method ( wPich I may on fome other opportunity explain ) I have been able prefently to examine the poffibility of it ; and if fo, as eafily to ex- cogitate divers wayes of performing it : And indeed it ispoffible to do as much by this method in Mechanicks, as by Algebra can be perform'd in Geometry. Nor can I at all doubt, but that the fame method is as ap- plicable to Phyfical Enquiries , and as likely to find and reap thence as plentiful a crop of Inventions ; and indeed there feems to be no fubjeH fo barrenfiut may with this good husbandry be highly improvd.
Toward the profecution of this method Phyfical Inquiries, / have here and there gleaned up an handful cf Obfervations, in the colleHion of mofi of which I made ufe o/Microfcopes, and fome other Glades and In- ftruments that improve the fenfe ; which way I have herein taken , not that there are not multitudes of ufeful and pleafant Obfervables,yet uncol- ldied,obvious enough without the helps of Art , hut only to promote the ufe of Mechanical helps for the Senfes, bath in the furveying the already vifible
World,
The P E F A C E.
Worlds and forthedifcoveryofman^ others hitherto unknown^ and to mak^ usyvith the great Conqueror yto be afehtedthat we have notyet overcome one World when there are fo many others to be difcovend^ every confiderable improvement Gf'Xc\cico'^c?> or Microfcopes producing new Worlds and Tcrra-Incognitasto our view.
The Glaffes lufed were cf our Engllfh mahejjut though very good of the kjnd^ yet far Jhort of what might be expe^ed^ could we once find a way of mahqng Glaffes Elliptical., or of fome more true fib ape ; for though both Microfcopes, and T elcfcopcs, as they now are., will magnifie an Objed about a thoufand thoufand times bigger then it appears to the naked eye ; yet the Apertures of the Objebii-glalfes are fo very final f that very few Rays are admitted, and even of thofe few there are fo manyfalfe, that the ObjeU appears dark ^;z^indiftind : And indeed thefe inconveniences are fuch,06 feern infeparable from Spherical Glaffes, even when mofi exaSily madefiut thtway we have hitherto made ufe of for thatpurpofe k fo imperfehl,that?^there may be perhaps ten wrought before one be made tolerably good, and mofi of thofe ten perhaps every one differing in goodnefi one from another, which k an Argument,thatthe way hitherto ufed k,at leafi,very uncertain. So that thefe Glaffes have a double dfeRi'ghe one,that very few of them are exactly true wrought ; the other, that even cf thofe that are befi among them, none will admit a fufficient number of Rayes to magnifie the Objehi beyond a determinate bignefi. Againfi which Inconveniences the only Remedies I have hitherto met with are thefe.
Firft, for Mkroficpes ( where the Objcdt we view is near and within our power)the bell: way of making it appear bright in the Glalsjis to call: a great quantity of light on it by means convex gUfies.gox therebyjthough the aper- ture be very fmalkyet there will throng in through it luch multitudesjthat an Objedc will by this means indure to be magnifi’d as much again as it would be without it. The way for doing which is this. I make choice of Ibme Room that has only one window open to the South , and at about three or four foot diftance from this Window jOn a Table, I place my Microfcope, and then fo place either a round Globe of Water, or a very deep clear piano con- vex Glals ( whofe convex fide is turn'd towards the Window ) that there is a great quantity of Rayes colleded and thrown upon the Objedt ; Or if the Sun fhine, I place a (mail piece of oyly Paper very near the Object, be- tween that and the light , then with a good large Burning-Glafs I lb colled and throw the Rayes on the Paper,that there may be a very great quantity of light pafs through it to the Objed 5 yet I lb proportion that light, that it
’ may
The Preface.
may not fingc or burn the Paper. Inftead of wbieh Paper there may be made ufe of a fraall piece of Looking-glafs plate , one of whole fides is made rough by being rubb’don aflat Tool with very fine land, this will, if the heat be leifurely call: on it, indure a much greater degree of heat, and con- fequently very much augment a convenient light. By all which means the light of the Sun, or of a Window, may be fo caft on an Objeft, as to make it twice as light as it would otherwife be without it, and that without any in- convenience of glaring, which the immediate light of the Sun is very apt to create in moft Objeds, for by this means the light isfo equally diffuled, that all parts are alike inlightned 5 but when the immediate Tight of the Sun falls on it, the reflexions from fome few parts are fo vivid, that they drown the appearance of all the other, and are themfelves alfo, by reafon of the in- equality of light, indiftind, and appear only radiant Ipots.
But becaule the light of the Sun, and alfo that of a Window, is in a conti- ’ nual variation, and fo many Objeds cannot be view’d long enough by them to be throughly examin’d 3 befides that , oftentimes the Weather is io dark and cloudy, that for many dayes together nothing can be view’d : And be- caufe alfo there are many Objeds to be met with in the night, which cannot (b conveniently be kept perhaps till the day, therefore to procure and caft a fufficient quantity of light on an Objed in the night, I thought of, and often ufed this. Expedient.
I procur’d me a fmall Pedeftal , foch as is deforib’d in the fifth Figure of the Scheme on the {mall Pillar A B, of which were two . movable Armes CD, which by means of the Screws EF, I could fix in any part of the Pillar 3 on the undermoft of thde I plac’d a pretty large Globe of Glais G, fill’d with exceeding clear Brine, ftopt, inverted, and fixi in the m^mner vifible in the Figure 3 out of the fide of which Arm proceeded another • Arm H, with many joynts 3 to the end of which was faftned a deep plain Convex glafs I, which by means of this Arm could be moved to and fro, and fixt in any pofture. On the upper Arm was placed a fmall Lamp K, which could be fo mov’d upon the end of the Arm , as to be fet in a fit pofture to give light through the Ball : By means of this Inftrument duly plac’d , as is exprefi: in the Figure, with the (mall flame of a Lamp may be caft as great and convenient a light on the Object as it will well indure5and being always conftant, and to be had at any time, I found moft proper for drawing the reprelentations of thofe fmall Objects I had occafion to obierve.
None of all which ways (though much beyond any other hitherto made ufe of by any I know ) do afford a fufficient help, but after a certain degree of magnifying,they leave us again in the lurch. Hence it were very defirable, that fome way were thought of for making the Objed-glaft of fuch a Figure as would conveniently bear a large Aperture,
As for Telefcopes, the only improvement they feem capable of is the increafmg of their length ; for the Objebi being remote^ there U no thought of giving it a greater light thin it has ; and therefore to augment the Aperture^ the Glajl mujl be ground of a very large ^here ; for ^by that . e meanSy
The P R E F A C E.
means^the longer ihe Gkjl be^ the bigger aperture mil it bear^if the Glafes be of an equal goodnefi in their kind, .Ther^ore a fix will indure a much larger Aperture then a three foot Glafi ; and a fiyty foot Glafl will proportionably bear a greater Aperture then a thirty ^and will as much ex- cel it alfo 06 a fix foot does a three foot,, as I have experimentally obfervd in one of that length made by Mr, Richard Reives here at London, which will bear an Aperture above three inches over , and yet mak^ the Objehi proportionably big and difinhi ; whereas there are very few thirty foot Glajfesthat will indure an Aperture of more then two in- ches over. So that for Telcfcopcs , fuppofing we had a very ready way of making, their Objehi Glafes of exahily ffherical Surfaces^ we might,, by increafwg the length of the Glafi,, magnifie the Objehi to any afignable big- nefl. And for performing both thefe,, I cannot imagine any way more ea^
fie,,and more exaht,, then by thus following Engine fy means of which,, any Glafes,,of what length foever^may be fpeedily made, It feems the moji eafie,, hecaufe with one and the fame Tool may be with care ground an Objeli Glajl,, of any length or breadth requifite , and that with very little or no trouble in fitting the Engine , and without much skill in the Grinder. It feems to be the moft exalt , for to the very loft firofie the Glafi does regulate and reHifie the Tool toitsexaH Figure ; and the longer or more ' the Tool and Glajl are wrought together,, the more exaH will both of them be of the defird Figure, Further,, the motions of the Glafi and Tool do fo crofi each other , that there is not one point of either s Surface fiut has thoufands of crofi motions thwarting it ,, fo that there can be no kind of Kings or Gutters made either in the Tool or Glafi,
The contrivance of the Engine is, only to make the ends of two large Mandrils fb to move , that the Centers of them may be at any convenient diftance afunder , and that the Axis of the Mandrils lying both in the fame plain produc’d, may meet each other in any aflignable Angle 5 both which reqiiifites may be very well perform’d by the Engine deferib’d in the third Figure of the Scheme : where A B fignifies the Beam of a Lath fixt per- pendicularly or Horizontally, C D the two Poppet heads, fixt at about two foot diftance, E F an Iron Mandril^whoik tapering neck F runs in an adapt- ed tapering brafs Collar 5 the other end E runs on the point of a Screw G ^ in a convenient place of this is faftned H a pully Wheel, and into the end of itjthat comes through the Poppet head C, is ferewed a Ring of a hollow Cj/linderK, or fome other conveniently fliap’d Tool, of what wideneis fliall
be
The Preface.
be thought moft proper for the cize of Glafles , about which it is to be ini° ploy’d: As, for Objeft glaffes, between twelve foot and an hundred foot long 3 the Ring may be about fix inches over , or indeed fomewhat more for thofe longer Glaifes. It would be convenient alfo, and not very chargeable 3 to have four or five feveral Tools, as one for all Glafles between an inch and a foot , one for all Glafles between a foot and ten foot long, another for all between ten and an hundrcdja fourth for all between a; hundred and a thoufand foot long; and if Curiofity lhall ever proceed fo far, one for all lengths between a thoufand and ten thouland foot long for indeed the principle is fuch,that fuppofing the. well madCjandof a
good length, and fuppofing great care be uled in working and polifliing them,I fee no reafon,but that a Glals of a thoufand,nay of ten thoufand foot long, may be as well made as one of ten ; for the reafon is the lame,fuppofing the Mandrils and Tools be made fufficiently ftrong, fo that they cannot bend ; and fuppofing the Glafs, out of which they are wrought, be capable of fo gi=eat a regularity in its parts as to reffadion ; this hollow Cylinder K is to contain the Sand, and by being drove round very quick to and fro by means of a fmall Wheel,which may be mov'd with ones foot, ferves to grind the Glafs : The other Mandril is fhap’d like this, but it has an even neck in- flead of a taper one, and runs in a Collar, that by the help of a Screw, and a joynt made like M in the Figure, it can be ftill adjuftned to the wearing or wafting neck : into the end of this Mandril is ferewed a Chock N, on which, with Cement or Glew is faftned the piece of Glafs Q_ that is to be form’d ; the middle of which Glafs is to be plac’d juft on the edge of the Ring, and the Lath OP is to be fet and fixt ( by means of certain pieces and ferews, the manner whereof will be fufficiently evidenc’d by the Figure) in fuch an Angle as is requifite to the forming of flich a Sphere as the Glals is dc- fign’d to be of ; the geometrical ground of which being fufficiently plain, though not heeded before, I fhall,. for brevities fake, pals over. Thislaft Mandrills to be made ( by means of the former, or Ibme other Wheel ) to run round very fwift alfo , by which two crols motions the Glals cannot chufe ( if care be us’d ) but be wrought into a moft exadly fpherical Surface.
But becaufe we are certain^ from the Laws of refraction ( which 1 I havee^erimentally founJtobe fofy an Infirument I p.mll prefently de^ feribe ) that the lines of the angles- of Incidence are proportio- nate to the lines of the angles of RefraClion, thereforeif Glapes could he made of thofe kind of Figures^ or fome other ^ fuch the moft incompa-
rable Les Cartes het^ invented^ and demonftrated in hks Philofophicaland Mathematical U^orks-tWe might hope for a much greater perfehiion of Optick^ then can be rationally expelled from fpherical ones\ for thoughyzxtcns^z- ribus, wefind^ that the larger the Telefcope OhjePi Glajfes are^ and the Jhorter thofe of the Microfco^e^ the better they magnifies yet both of thew.^
The Preface.
befiJi fuch determinate Jimenfions , are by certain inconveniences rendred unufeful; for it willhe exceeding difficult to make and manage aTube above an hundred foot long, and it will be as difficult to inlightcn an Objebi lejl then an hundted part of an inch dijlant from the Obje^i GlaJ^, I have not as yet made any attempts of that kind^ though I know two. or three w^es^ whicb^ as far asl have yet confidered^ feem very prohable^and may invite me to mak§ a try at as foon as I have an opportunity^ of which I may hereafter perhaps acquaint the world. In the Interim ^ I pjalldefcribe the Inftrument I even now mention'd^ by which the refrz^’ion of all kinds of Liquors may be mofl exaHly meafurd^ thereby to give the curious an opportunity cf making what further try ah (f that kind they ffall think requifite to any of their intended try ah ; and to let them fee that the laws of RefraHion are not only notional.
The Infti'umcnt confifted of five Rulers , or long pieces placed together, after the manner cxpreft in the fecond Figure of the firft Scheme y where A B denotes a ftraight piece of wood about fix foot and two inches long, about three inches over, and an inch and half thick , on the back fide of which was hung afmall plummet by a line ftrctcht from top to bottom, by which this piece was fet exactly upright,and fo very firmly fixt 5 in the mid- die of this was made a hole or center, into which one end of a hollow cy- lindrical brafsBox CC, fafhion'd asifihallby and by defaibe, v/as plac’d, and could very eafily and truly be mov’d to and fro ^ the other end of this Box being put into, and moving in, a hole made in afmall arm DDi into this box was faftned the long Ruler E F, about three foot and three or four inches long, and at three foot from the above mention'd Centers P P was a hole E, cut through, and crols’d with two fmall threads, and at the end of it was fixt a Imall fight G, and on the back fide of it was fixt a fmall Arm H, with a Screw to fix it in any place on the Ruler L M ^ this Ruler L M was mov’d on the Center B ( which was exactly three foot diftance from the middle Center P ) and a line drawn through the middle of it LM, was divided by a Line of cords into Ibme fixty degrees,and each degree was fub- divided into minutes , fo that putting the crofs of the threads in E upon any part of this divided line , I prelently knew what Angle the two Rules A B and E F made with each other^ and by turning the Screw in H, I could fix them in anypofition. The other Ruler allb RS was made- much aftet; the lame manner, only it was not fixt to the hollow cy lindrical Box, but,by means of two fmall brais Armes or Ears, it mov’d on the Centers of it 5 thisalfo, by means of the crofs threads in the hole S, and by a Screw in K, could be faftned on any divifion of another line of cords of the fame radius drawn on N O. And fo by that means, the Angle made by the two Rulers, A B and R S, was allb known. The Brafs box CC in the middle was lhap’d very much like the Figure X, that is, it was a cylindrical Box ftopp’d clofe at ei- ther end, off of which a part both of thefides and bottomeswascutout, lb
that
The Preface.
that the Box, \^hen the Pipe and that was joyne d to it;, would contain the Water when fill’d half full, and would likewife, without running over^ in- dure to be inclin’d to an Angle j equal to that of the gteatefi: refraiSion of Watetj and no morejWithout running over. The Ruler E F wasfixt very fall to the Pipe Vj fo that the Pipe V dirededthe length of the RulerE Fjand the Box and Ruler were mov’d on the Pin TT, (b astomakeahydefi- rable Angle with the Ruler AB. The bottom of this PipeV wasftop’d with a fmall piece of exactly plain Glafs j which was plac’d exaftly per- pendicular to the Line of diredtion^ or of the Ruler E F. The Pins alfo T T were drilfd with fmall holes through the Axis^^nd through thofe holes was firetcht and faftned a fmall Wire. There was likewife a fmall Pipe of Tin loofiy put on upon the end of V, and reaching down to the fight G 5 the ufeof which was only to keep any falle Raves of light from palling through the bottom of V;) and only admitting llich to pals as pier- ced through the fight G; All things being placed together in the manner deferib’d in the Figure 5 that is, the Ruler A B being fixt perpendicular, I fill’d the Box C C with Water, or any other Liquor, whofe refradlion I in- tended to try 3 till the Wire pafling through the middle of it v/ere juft co- vered : then I moved and fixt the Ruler F E at any aflignablc Angle, and placed the flame of a Candle juft againft the fight G x and looking through the fight I, I moved the Ruler R S to and fro, till I perceived the light paF fing through G to be covered, as ’twere, or divided by the dark Wire paF fingthrough PP: then turning the Screw i.iK, I fixt it in that pofture: And through the hole S, lobferved what degree and part of it was cut by the crofs threads in S. And this gave -me the Angle of Inclination, APS anftveringto the Angle of Refraftion BPE : for the furfaceof the Liquor in the Box will be alwayes horizontal , and confequently A B will be a perpendicular to it 5 the Angle therefore APS will mcafure, or be the Angle of Inclination in the Liquor 5 next EPB muftbe the Angle of Re- fradion,for the Ray that paftes through the fight G, paftes alfo perpendicu- larly through the Glafs Diaflragme at F, and confequently alfo perpendi- cularly through the louder furface of the Liquor contiguous to the Glafs, and therefore fuffers no refraaion till it meet with the horizontal furfaceof the Liquor in C C, which is determined by the two Angles.
By means of this Injlrument lean with\\xx\.t trouble, and a very fmall quantity of any Liquor, examine^ rnoft accurately^ the refradion of it , not only for one inclination^ but for all ; and thereby am inabled to make very accurate Tables ; fever al of which I have alfo experimentally made^and find^ that Oylof Turpentine has a much greater RefraHion then Spirit of Wine , though it be lighter ; and that Spirit of Wine has a greater BefralHon then Water, though it be lighter alfo ; hut that lalt Water alfo has a greater RefraHion then frefh, though it be heavier : but Allum water has a lef tefraHlon then common Water, though hea-^ vier alfo. So that it feems^as to the refradion made in a Liquor f he ipeci-
The Preface.
fick gravity li of no efficacy, By thhihave alfofound4hatlook.what^vo^ portion the Sine of the Angle of Inclination ho6to the Sineo^' Angle of Refradion, correffondent toit^ the fame proportion have all the Sines (f other Inclinations to the Sines of their appropriate Refr anions,
My way for meafuring how much a Glafs magnifies an Objefl:, plac’d at a convenient diftance from my eye^is this. Having reftifi’d the Microfiope^ to fee the defir’d Objeft through it very diftinftly, at the fame time that I look upon the Objeft through the Glafs with one eye, I look upon other Objeds at the fame diftance with my other bare eye 3 by which means I am able, by the help of a divided into inches and fmall parts, and laid on the Pedefial of the Mkrofcope^to caftjas it were, the magnifi’d appearance of the Objed upon the Ruler, and thereby exadly to meafure the Diameter it ap- pears of through the Glafs, which being compar’d with the Diameter it ap- pears of to the naked eye , will eafily afford the quantity of its magnify- ing.
The Microfcope^ which for the moft part I made ufe of, was fhap’d much like that in the fixth Figure of the firft Scheme^ the Tube being for the mofi: part not above fix or feven inches long, though, byreafon it had four Draw- ers, it could very much be lengthened, as occafion required 5 this was con- triv’d with three Glafles^a fmall Objed Glafs at A, a thinner Eye Glafs about B, and a very deep one about C : this I made ufe of only when I had oc- cafion to fee much of an Objed at once 5 the middle Glafs conveying a very great company of radiating Pencils, which would go another way, and throwing them upon the deep Eye Glafs. Rut when ever I had occafion to examine the fmall parts of a Body more accurately , I took out the middle Glafs,and only made ufe of one Eye Glafs with the Objed Glafs, for always the fewer the Refradions are, the more bright and clear the Objed appears. And therefore ’tis not to be doubted , but could we make a Microfeope to have one only refradion, it would, ceteris paribus^ far excel any other that had a greater number. And hence it is, that if you rake a very clear piece of a broken Few/Ve Glafs, and in a Lamp draw it out into very fmall hairs or threads, then holding the ends of thefe threads in the flame, till they melt and run into a fmall round Globul, or drop, which will hang at the end of the thread ^ and if further you flick feveral of thefe upon the end of a flick with a little fealingWax,fo as that the threads frand upwards, and then on aWhetflonefirflgrind off a good part of them, and afterward on a fmooth Metal plate, with a little Tripoly, rub them till they come to be very fmocth, if one of thefe befixt with a little foft Wax againfl a fmall needle hole,prick’d through a thin Plate of Brafs, Lead, Pewter, or any other Me- tal, and an Objed, plac’d very near, be look’d at through it, it will both magnifie and make feme Objefts more diflind then any of the great fcopes. But becaufe thefe, though exceeding eafily made, are yet very trou- blefometo be us’d,becaufe of their fmalnefs,and the nearnefsof the Objed 3 therefore to prevent both thefe, and yet ha ve only two Refradions, I pro- vided me a Tube of Brafs, fhap’d much like that in the fourth Figure of the firfl Scheme 5 into the fmaller end of this I fixt with Wax a good piano con- vex
The Preface.
Objed GlafsjWith the convex fide towards the Objed'j and into the bigger end I fixt alfo with wax a pretty large piano Convex Glafs, with the convex - fide towards my eye , then by means of the fmall hole by the fide , I fill’d the intermediate fpace between thefe two Glaflfes with very clear Water, and with a Screw flopp’d if in 5 then putti&g on a Cell for the Eye, I could perceive an Ob jed more bright then I could when the intermediate fpace was only. fiird with Air_,but this, for other in- conveniences, I made but little ufe of. '
My way for fixing both the Glafs and Objefb to the Pcdeftal moft conve- niently was thus : Upon one fide of a round Pcdeftal A B, in the fixth Fi- gure of the firft Scheme fixt a Imall Pillar C C, on this was fitted a Imall Iron Arm D, which could be mov’d up and down, and fixt in any part of the PiUarjby means of a fmall Screw E 5 on the end of this Arm was a fmall Ball fitted into a kind of focket F,made in the fide of the Brals Ring G, throng ' which the fmall end of the Tube wasfcrew’d^ by means of which contri- vance I could place and fix the Tube in what pofture I defir’d ( which for many Obfervations was exceeding neceflary ) and ad juften it moft exactly toanyObjeft.
For placing the Objed,! made this contrivance 5 upon the end of a fmall brals Link or Staple H H, I fb faftned a round Plate 1 1, that it might be turn’d round upon its Center K , and going pretty ftiff , would ftand fixt in any pofture it was fet 5 on the fide of this was fixt a fmall Pillar P, about three quarters of an inch high, and through the top of this was thruft. a fmall Iron pin M, whofe top juft flood over the Center of the Plate 5 on this top I fixt a fmall Gbjed, and by means oi thefc contrivances I was able to turn it into all kind of pofitions, both to my Eye and the Light 5 for by moving round the fmall Plate on its center, I could move it one way, and by turning the Pin M, I could move it another way , and this without ftirring the Glafs at all , or at leaft but very little : the Plate likewife I could move to and fro to any part of the Pedeftal ( which in many cafes was very con- venient) and fix it alfo in any Pofition, by means of a Nut N, which was ferew’d on upon the lower part of the Pillar C C. All the other Con- trivances are obvious enough from the draught, and will need no defeription
Now though thk vpcre the Inftrument I made moft ufe oft yet I have made fever al other Try ah with other kinds of which both
for and forvciwere very dijferent from common ft^herical Glaffes, lhave made a Microfeope with one piece of Glaft^ both whofe furfac-es were plains. I have made another only with a piano concave, without any kind of reflebiion^ divers alfo by means of refledion. I have made
ethers Waters, Gums, Refins, Salts, AiTenick, Oyls, and with divers other mixtures 0/ watery and oy\y Liquors. Andindeedthe fubje5i PS capable of a great variety ; but I find generally none more ufe^ fulthenthat which ia made with two fitch asl have already de^-
What
The Preface.
What the things are I obfervd^ the following defcriptions will manifefi ; in brief they were either exceeding fmall Bodies, or exceeding fmall Pores, or exceeding fmall Motions, fome of each of which the Reader will find in the following Notes^and fuch^ as I prefmnCy ( maj^ of them, atkafl')willbe new, and perhaps not lefi ftrange; Some fpecimeri of each of which Heads the Reader will find in the fubfequent delineations^ and indeed of fome more then I was willing there fljould be-,, which Was occafioned by my firfl Intentions to print a much greater number then I have fence found time to compleat. Of feuch therefore as lhad^l fdefi- edonly fome few of every Head^ which for fome particulars feerndmoflob- fervable^ rejeHing thcrefe as feuperfluous to the prefent Defegn.
What each of the delineated Subjects areqthe following defcriptions an^ next to each will inform^of which I fejallhere^ only once for alf add^ That in divers cf them the Gravers have pretty well follow d my direHions and draughts ; and that in making of them^ I indeavouted Q as far as Iwas able ) firfl to difeover the true appearance , and next to mak^ a plain re- prefentation of it. This I mention the rather , becaufe of thefe kind of ObjeHs there is much more difficulty to difeover the true floape , then cf thofe vifeble to the naked eye^ the fame ObjeM feeming quite differing^ in one pofition to the Light,, from what it really is,, and may he difeover d in another. And therefore I never began to make ary draught before by
many examinations in feveral lights^ and in fever al pofitions to thofe lights,, I had difeover' d the true form. For it is exceeding difficult in fome Objebis , to difeinguifh between a prominency and a depreffion^ between a (hadow black ftain, ora reflexion ^;?^^whitenefs in the colour. Befides,, the tranffarency of mofe ObjeHs renders them yet much more difficult then if they were opacous. Tl)e Eyes of a Fly in one kind of light appear almofi like a Lattice,, drill'd through with abun- dance of fmall holes ; which probably may be the Reafon, why the Ingeni- ous Dr. Power feems to fuppofe them feuch. In the Sunfhine they look, like a Surface cover'd with golden Nails ; in another pofeurejikc a Sur- face cover'd with Pyramids ; in another with Cones ; and in other po- fiuresof quite other flj apes \ but that which exhibits the beft,, is the Light collePled on the Objelt,, by thofe means 1 have already deferib'd, ,
/
The Preface.
And th'ps undertaken in profecution of the ^efign which the ROY- AL SOCIETY ho6 propos'd to it felf For the Members of th'e Affemhly ha- ving before their eys fomany fatal Infiances of the errors and faljhoodsfn which the greatefipart of mankind has fo long wandred^ becaufe they rely d upon the firength oj humane Eeafon alone ^ have begun anew to correH all Hy- porhefes by fenfe^ cus Seamen do their dead Reckonings by Coeleftial Obfervations;^;?^ to thispurpofe it has been their principal indeavour to en- large isf ftrengthen the Senfes by Mcdicine^and by fuch outward Inftru- ments as are proper for their particular works.. By this means they find form reafon to fufiehi^hat thofe efehts ofBodiesyvhich have been commonly attri- buted to Qualities, and thofe confejl’d to be occult, are perform' dby the Machines of Nature.^ which are not to be difeernd without thefe helps^ feeming themeerproduHs ofMotion^Figurc^and Magnitude; and that the Natural Textures, which forne call the Plaftick faculty, may be made in l.oomsyvhich a greater perfehrion of Opticks may make difcernable by thefe Glaffesfo as now they are no more puzgled about themyhen the vulgar are to conceive fiowT2c^t.?iry or fiowred Stuffs are woven. And the ends of all thefe Inquiries they intend to be the Pleafurc of Contemplative minds^ but above all^he eafe and difpatch cf the labours of mens hands. They do indeed neg- leH no opportunity to bring all the rare things of Remote Countries within the compafi of their knowledge and pr alike. But they fiill acknowledg their moft ufeful Informations to arifefrom common things., and from diverfifying thexr mofi ordinary operations upon them. They do not wholly rejeH Experi- ments cf meer light and theory ; but they principally aim at fuch., whofi Applications will improwe. Tend facilitate the prefentway ^Manual Arts. And though fomemen., who are perhaps taken up about lefi honourable Em~ ployments., are pleas'd to cenfure their proceedings., yet they can fhewmore fruits cf their firfi three years., wherein they have, off embled., then ary other Society in Europe can for a much larger /pace cf time.'Tis true., fuch un- dertakings m theirs do commonly meet with fmallincouragement ., becaufe men are generally rather taken with the plaufible and difcurfive, then the real and the folid part of Philofophy ; yet by the good fortune of their inflitu- tionfn an Age of all others the mofi\n(o^\i\I\mc^chey have been afflfied by the contribution and prefence ^ very many of the chiefFloMihcy and Gentry,
g and
The Preface.
and other s^vfho are fome of the moft confiderable in their fever al Profefions. But that that yet farther convinces me cf the Real efteem that the more fe- rious part of men haveof thhSocicty^k^that fever al Merchants, aPx in earneft(whofe Objeld h meum isn\mrc\^that great Rudder (f humane affairs')have adventur'dconfiderahle fums of Money 40 put in prabUcewhat fome of our Members have contrived^ and have continued ftedfaft in their good opinions of fuch Indeavours^ when not one of a hundred of the vulgar have believed their undertakings feafable. And it is alfofit to be addedyhat they have one advantage peculiar to themfelves^hat very many of their num- ber are men of Converfe and Traffick ; which is a good Omen^ that their attempts will bring Philofophy from words to 2.d.\on feeing the men ofBufi- nefi ha ve had fo great a ffaare in their fir ji foundation.
And of this kind I ought not to conceal one particularGeneroitty^which more nearly concerns my felfit is the munificence of Sir JohnCutler,?;2 endowing a Lehiurefor the promotion o/Mechanick Arts, to be governed and directed byJhisSociQty .7 bis^ounty I mention for the Honourablenefs of the thing it felfandfor the expehiation which I have of the efficacy of the Example for it cannot now be objected to themy^hat their Defigns will be efieerned frivolous andwTiin.^ when they have fuch a real Teftimonyo/ the Approbation of a Man that is fuch an eminent Ornament (f this renowned City., and one., whofy Variety, and happy Succefs, (f his negotiations.^ has given evident proofs., that he is not eafie to be deceiv'd. This Gentleman has well obfervd., that the Arts of life have been too long imprifon’d in the dark, fibops of Mechanicks themfelvesds there hindred from growth, by ig- noranceyor felfinterefi:and he has bravely freed them from thefe inconveni- cnccsiHehath not only obliged 'Vr2.dt{vc\(st\fiut Tradeit felfiHe has done a work that is worthy of London, and has taught the chief City of Commerce in the world the right way how Commerce istobeimprov d. We have already feen many other great figns of Liberality and a large mind., from the fame hand:For by his diligence about t^eCorporation for the Poor ;^ji his hono- rable Subferiptions/or the rebuilding of St.PzuYsfiy hkchearful Disburf- ment for the replanting o/Ireland,(Z«^/ by many other fuch publick works, he has fhewn by what means he indeavours to eftablifh Afr/Tzo/y ; und now by this laftgift he has done thafgwhkh became one of the wifeft Citizens
of
The Preface.
(four Nation to accomplijh^ feeing one of the wifeft of our Sratefmen,the Lord Verulam, propounded it.
But to return to my Subje^^from a digrejfwn^ which^ Ihope^my Reader mil pardon me^ feeing the Example k fo rare that lean mak^no more fuch digreffions. Ifthefe my firfi Labours fljallbe any wayes ufefulto inquU ring men^ I muft attribute- the ineouragement andpromotion of them to a ve- ry Reverend W Learned vphom thk ought in juf ice to be faid^
That there is fcarce any one Invention, which this Nation has pro- duc’d in our Age, but it has force way or aher been fet forward by his affiftance. My Reader fbelieveyrill quickly ghejl^that it k Dr. Wil- kins that I mean. He k indeed a man horn for the good of rmnVm&.^and for
honour of Country. In the {weetne(s<3/ whofebd-mioweynthe calmnefs -o/ hk mind, in the unbounded goodnefs oj hk heart, we have an evident Inftance., what the true and the primitive unpafoonate Religi- on bfore it was fowred by particular FaSions. h a word.^ hk Zeal has been fi conftant and ededuaJ in advancing all good and profitable Aris^hat as one (f the Antient Romans faid <^Scipio, That he thanked God that he was a Roman ; becaufo whereever Scipio had been l>orn, diere had been the foat of the Empire of the world : So may I than! God.^ that Dr. Wilkins Englifhman, jor whereever he had lived., there hadbeen the chief Seat of generous Knowledge and true Phiioib- phy . To the truth of thkyhire are fs many worthy men living that will fuh- feribe., that I am confident., what 1 have here fauf will not be Ipokid upon., by aipj ingerimtus Reader ^ Panegyrick, but only 06 ^ real tefli-
mony, .c
By the Advice (f thk Escelient man I firji fa upoa thk Enterprife^ya fiill came to it with much Btlv^^ncy fiecaufe I was to follow the footflepsof fo eminertta Perfon as Dr. Wren , who was the firfi that attempted any thing cf thk nature ; whofe original draughts do now mah^ one of the Orna- ments of that great Collection cf Rarities in the Kings Clofct. Thk Ho- nor, which hk firfi beginnings of thk kind have receiv'd., to be admitted in- to the mofi famous place of the world filid not fo much incourage, as the ha- zard of coming after Dr. Wren di// affright me ; for of him Imufi affirm., ^thatffince the time Archimedes, there fcarce ever met in one man., in fo
great
The Preface.
great a, perfeciion^ fuch a Mechanical Hand, anJ fo Philofophical Mind.
But at lajlj)dng affuredboth by Dr. Wilkins, Dr. Wren himfelf\ that he had given over hi^ intentions of profecuting it^ and not finding that there veas any elfe defignd the purfuing of itjfet upon thk undertakings and W06 not a little incouragd to proceed in itsbythe Honour theRoysl Society W06 pleas'd to favour me withsin approving of thofe draughts (which from time to time as I had an opportunity of defcribingf I prefented to them. And particularly by the Incitements of divers of thofe Noble and excellent Per^ fons of its ^ore efpecial Friends^who were not lefi urgent with
me for thepublijfnngs then for the profecution of them.
After I had almofi compleated thefe Piltures and Obfervations ( ha~ ving had divers of them ingraven , and was ready to fend them to the Prefix I was inform'd s that the Ingenious Phyfitian F)r, Henry Povfer had made Microfcopical ObfervationSswhich had I not afterwar ds^ upon our interchangably viewing each others Papers^ found that they were for the moftpart difering from mines either in theSubjeH it felfs or in the particulars tak^n notice of ; and that his defign was only to print Obfer- vations without PiUureSsI had even then fuppreflcd what Ihad fo farpro-^ ceeded in. But being further excited by fever al of my Friendss in compty- ance with their opinionss that it would not be unacceptable to fever al inqui- fitive Mens (tnd hoping alfo , that I Jhould thereby difcover fomething New to the Worlds I have at length cafl in my Mitel into the vaft Treafu- rycf A Philofophical Hiftory. And it k my hope, as well as belief^ thsrt thefe my Labours will be no more comparable to the Produftions of many other Natural Philofophers, who are now every where bufie about greater things ; then my little Obje&s are to be compar'd to the greater and more beautifulN oxVs of Nature, A Fleas ^ Mitts ^ Gnats to anHorfesan Ele- phants or a Lyon* \
SOME
I
*.^xZ V.'Rtr «fll> *ij*> •> CW-
^5.45 143242 C43
T|GrT.fS''5r« ^ ^ ^ '»s«' <^ *-T^ ‘'i** ^ *-3^
*3>»
M I C R O G R- A P H I A,
OR SOME
Phyfiological Defcriptions
M I N U T E B O D I E S
MADE BY
magnifying GLASSES;
. WITH
Observations and I n q_u i R i e s thereupon.
Obferv. I. Of the Point of a Jharp fmallNeedki
S i'n Geometry^ the moft natural way of beginning is Sehem.26 from a Mathematical ^ ib is the fame method in Fig.io Obfervations and Natural hijiory the moft gcnuinCjlim- ple, and inftruftive. We muft firft endevour to make letters^ and draw fugle ftrokes true , before we ven- ture to write whole Sentences , or to draw large Pi- Bures. And in Phj/fcal Enquiries, we muft endevour to follow Nature in the more plain and eafe ways fhe treads in the moft ^mple and uncompounded bodies^ to trace her fteps, and be acquainted with her manner of walking there, before we venture our felves into the multitude of meanders fhe has in bodies of a more complica- r(?<3f nature 5 left, being unable todiftinguilh and judge of our way, we quickly lofe both Nature our Guide,and our felves too.and are left to wan- der in the labyrinth of groundleft opinions 5 wanting both judgment^ that lights and experience^ that c/era?, which fhould diredb our proceedings.
We will begin thefe our Inquiries therefore with the Obfervations of Bodies of the moft fmple nature firft,and fo gradually proceed to thole of a more compounded one.in profecution of which method,we fhall begin with a Thyfcal point-^ of which kind the Point of a Needle is commonly reckon’d for one , and is indeed, for the moft part, made fo lharp, that the naked eye cannot diftinguilli any parts of it : It very eafily piercesj and makes its way through all kind of bodies fofter then it felftBut if view’d with a very good Microfcope^ we may find that the top of a Needle (though as to the
B fenfe
Micrographia.
fenle very J/jarp) appears a Iroadjflnnt^ and very irregular etid j not referh-’ bJing a Cone, as is imagin'd, but onely a piece of a tapering body, with a great part of the top remov’d, or deficient. The Points of Pins are yet more blunt, and the Points of the moft curious Mathematital Inftruments do very feldome arrive at ib great a (harpnefs ^ how much therefore can be built upon demonftraticns made onely by the productions of the Ru- ler and Compafles, he will be better able to confider that fliall but view thofe points and lines with a Microfcope,
Now though this point be commonly accounted the fharpeft (whence when we would exprcfe the fharpnels of a point the moft jitperlatively^ we fay. As (harp as a Needle) yet the Microfcope can afford us hundreds of In- ftances of Points many thoufand times Iharper : fuch as thofe ofthe^^ir/, and brijilesy and claros of multitudes of Infect 5 the thorns , or crooks^ or hairs of leaves^ and other fmall vegetables 3 nay, the ends of the Jiiri(e or finall parallelipipeds of Amiatithns , and alumen plnmojitm 3 of many of which, though the Points are fo (harp as not to be vifible, though view’d with a Microfcope (which magnifies the ObjeCl:, in bulk, above a million of times) yet I doubt not, but were we able praBically to make Microfcopes according to the theory of them, we might find hills, and dales,and pores, and a lufficient bredth, or expanfion, to give all thofe parts elbow-room, even in the blunt top. of the very Point of any of thefe fo very fharp bodies. For certainly the qttantity or extenfion of any body may be Divif ble in in- finitum^ though perhaps not the matter.
But to proceed : The Image we have here exhibited in the firft Figure, was the top of a fmall and very ftiarp Needle, whofe point a a neverthelefs appear’d through the Microfcope above a quarter of an inch broad, not round nor flat , but irregular and un- even 3 fo that it feem’d to have been big enough to have afforded a hundred armed Mites room enough to be rang’d by each other without endangering the breaking one anothers necks, by being thruft off on ei- ther fide. The furface of which, though appearing to the naked eye very fmooth,could not neverthelefs hide a multitude of holes and feratches and ruggedneffes from being difeover’d by the Microfcope to inveft it, feveral of which inequalities (as A,B,C, feem’d holes made by fbme fmall fpecks of Rujl 3 and D fbme adventitious body^ that ftuck very clofe to it) were ca- Jual. All the reft that roughen the furface, were onely fb many marks of the rudenefsand bungling of Art. So unaccurate is it, in ail its producti- ons, even in thofe which feem moft neat, that if examin’d with an organ more acute then that by which they were made, the more we fee of their jhape^ the lefs appearance will there be of their beauty : whereas in the works of Nature^ the deepeft Difeeveries fhew us the greateft Excellen- cies. An evident Argument, that he that was the Author of all thefe things, was no other then Omnipotent 3 being able to include as great a va- riety of parts and contrivances in the yet fmalleft Difeernable Point, as in thofe vafter bodies (which comparatively are called alfo Points) fuch as the Earthy Sun^ or Planets. Nor need it feem ftrange that the Earth it felf may be by ^nAnalogie call’d aThyfical Point:For as its body, though now
3
MiCROGP. APHIA.
lb near US as tofilloureys and fancies with a fenleof the vaftncls of it, may by a little Difiance, and fome convenient DimittiJInng Glafles, be made vanifh into a fcarce vifible Speck, or Point (as I have often try’d on the and (when not too bright) on the Sun it felf.) So,
could a Mechanical contrivance fuccesfully anlwerour iheory^ we might fee the leaft fpot as big as the Earth it ielf 5 and Difcover, as Des Cartes Dief- ck alfo con jedures, as great a variety of bodies in the or Vianet s^ as in ^ 5
the Earth.
But leaving thefe Difcoveries to future Induftries, we (hall proceed to add one Obfervation more point commonly fo Call’d, that is, the mark
of zpiU jtop. or period. And for this purpofe I obferved many bothprinted ones and written ^ and among multitudes I found /in? of them more round or regular then this which I have delineated in the third figure of the fe- cond Scheme, but very many abundantly disfigur’d'^ and for the moft part if they feem’d equally round to the eye, I found thole points that had been made by a Copper-plate^ and Roll-prels, to be as mislhapeft as thofe which had been made with Types ^ the moR curious andfmothly engraven Jirokes and points^ looking but as fo many furrows and holes ^ and their printed imprejfions, but like fmutty daubings on a matt or uneven floor with a blunt extinguilht brand or ftick’s end. And as £or points made with zpen they were much more rugged and deformed. Nay,having view’d certain pieces of exceeding curious writing of the kind ( one of which in the bredth of a two-pence compris’d the Lords prayer^ the Apojlles Creed^ the ten Commandments^ and about half a dozen verfes befides of the Bible^ whofe lines were fo fmall and near together^ that I was unable to number them with my nakgd eye^ a very ordinary Microfope^ I had then a- bout me,inabled me to fee that what the Writer of it had aflerted was true^ but withall difoover’d ofwhatpitifull bungling fcribbles and (crawls it was compos d^Arabi an and China characters being almofi: as well fhap’d 5 yet thus much I muft fay for the Man, that it was for the moft part legible enough, though in ibme places there wanted a good fantjy well prepojeji to help one through, if this manner oi fmall writing were made efiie and praBicable ( and I think I know fuch a one, but have never yet made tryal of it, whereby one might be inabled to write a great deale with much eafi^ and accurately enough in a very little roome ) it might be of very good ufo to convey fecret Intelligence without any danger of Difcovery or mijirujiing. But to come again to the point, 'thclrregularities oh\t are caufed by three or four coadjutors^ one of which is, the imeven furfacc oC the paper ^ which at belt appears no Imother then a very courfo piece of jhagd cloth^ next the irregularity of the Type or Ingraving.^ and a third is the rough Daubing of the Printing-Inkthat lies upon the inftrument that makes the impreflion, to all which, add the variation made by the Different lights and fijadows^ and you may have fufficient reafon to ghels that a peint may appear much more ugly then thk^ which I have here prefented, which though it appear’d through the Microfeope gray^ like a great Iplatch of London dirt, about three inches over 5 yet to the naked eye it w^asblacf^ and no bigger then that in the midft of the Circle A. And could I have
found
4
Micrographia.
found Room in this Plate to have inferted an O you Ihould have feen that the letters were not more diftind then the points of Diftindion, nor a drawn circle more exadly Jb^thcn vve have now (hown a point to be zpeint.
Obferv. II. Of the Edge of a Razor.
Schtm.7. ^■r’'He fharpeft Edgehzth. thelame kind of affinity to the fharpeftPw^t
-f’X- 2. J in Phyficks, as a line hath to apoint in Mathematicks 5 and therefore the Treaty concerning this, may very properly be annexed to the for- mer. A Razor doth appear to be a Body of a very neat and curious a- fpetl:, till more clofely viewed by the Microfeope^ and there we may ob- ferve its very Edge to be of all kind of fliapcs, except what it Ihould be. For examining that of a very (harp one, I could not find that any part of it had any thing of fliarpnefs in it 5 but it appear’d a rough forface of a very confiderable bredth from fide to fide, the narrowed part not leem- ing thinner then the back of a pretty thick Knife. Nor is’t likely that if ftiould appear any otherwife, fince as we juft now (hew’d that a point ap- pear’d a circle^ ’tis rational a line ftiould be a parallelogram.
Now for the drawing this fecond Figure( which reprefents a part of the Edge about half a quarter of an inch long of a Razor well fet) I ilb plac’d it between the Objed-glals & the light, that there appear’d a refledtion from the very Edge,repreiented by the white line abode fin which you may perceive it to be fomewhat ftiarper then elfewhere about dy to be indent- ed or pitted about by to be broader and thicker about c, and unequal and rugged about e, and pretty even between a b and e f. Nor was that part of the Edge g hi fmooth as one would imagine lb Imooth bo-
dies as a Hone and Oyl Ihould leave it 5 for befides thole multitudes of Icratches, which appear to have raz’d the furface ghik^y and to crols each other every way which are not half of them expreft in the Figure, there were leveral great and deep Icratches, or furrows, fuch zs gh and i k.y which made the furface yet more rugged, caus’d perhaps by Ibrae finall Duft cafually falling on the Hone, or Ibme harder or more flinty part of the Hone it lelf The other part of the Razor / /, which is polilh’d on a grinding-ftone, appear’d much rougher then the other, looking al- moft like a plow'd field, with many parallels, ridges, and furrows, and a cloddy, as ’twere, or an uneven furface ; nor lhall we wonder at the roughnefl'es of thofe furfaces , fince even in the moft curious wrought Glaflesfor Microfeopesy and other Optical ufes, I have, when the Sun has fticne well on them , dilcover’d their liirfacc to be varioully raz’d or lcratched,and toconfiftofan infinite of Imall broken liirfaces, which re- fledc the light of very various and differing colours. And indeed it leems impolfible by Art to cut the liirface of any hard and brittle body fmooth, fince VtittCy or even the moft curious Powder that can be made ufe of, to polifli liich a body, muft confift of little hard rough particles, and each of them muft cut its way, and conlequcntly leave Ibme kind of gutter or
furrows .
5
Micrographia.
furrow behind it. And though Nature does fcem to do it very readily m all kinds of fluid bodies , yet perhaps future obfervators may difcover even thcfe alfo rugged 5 it being very probable, as I elfewhere (hew, that fluid bodies are made up of fmall folid particles varioufly and llrongly mov’d, and may find reafon to think there is fcarce a furface in rerttm na* tura perfedly fmooth. The black fpot m », I ghefs to be fome fmall fpeck of ruft, for that I have oft obferv’d to be the manner of the working cTCorrofiveJuyces. To conclude, this Edge and piece of a Razor, if it had been really fuch as it appear’d through the Microfcope^ would fcarce- ly have ferv’d to cleave wood, much lefs to have cut off the hair of beards, unlefs it were after the manner that Lncian merrily relates to have
made ufe of, when with a Carpenters Axe he chop’d off the beard of a lage Philofopher, whofe gravity he very cautioufly fear’d would indanger the overfetting of his Wherry.
Obferv. III. Of fim Lawn^ or Limen Cloth.
THis is another produd of Art, A piece of the fineft Lawn I was able to get, fo curious that the threads were Icarce dilcernable by the na- ked eye,and yet through an ordinary Mkrofcope you may perceive what a goodly piece of coarfe Matting it is 5 what proportionable cords each of its threads are, being not unlike, both in fliape and fize, the bigger and coarfer kind of J/»^/e2J(?fe-_;'<?r»,wherewith they ulually make C'rf/'/ey. That which makes the Lawn fo tranfparent, is by the Mkrofcope^ nay by the naked eye, if attentively viewed, plainly enough evidenced to be the multitude of fquare holes which are left between the threads, appearing to have much more hple in relped of the intercurrent parts then is for the nioft part left in a lattke-vpindorp^ which it does a little refemble, oncly the crolftng parts are round and not flat.
Thefe threads that compofe this fine contexture, though they are as foiall as thole that conftitute the finer forts of Silks, have notwithftanding nothing of their gloflie, pleafant,and lively refledion. Nay, I have been informed both by the Inventor himfolf, and feveral other eye-witnefles, that though the flax,out of which it is made,has been {by a lingular art, of that excellent Perfon, and Noble Vertuofo, M. Char Is Howard^ brother to the Duke ofNorfolli)fo curioufly drels’d and prepar’d,as to appear both to the eye and the touch, full as fneznd asglojjie^ and to receive all kinds of colours,as well as Sleave-Silk 5 yet when this Silken Flax is twilled into threads, it quite lofeth its former luller, and becomes as plain and bale a thread to look on, as one of the lame bignels, made of common Flax.
The reafon of which odd Phenomenon foems no other then this 5 that though the curioufly dreft Flax has its parts fo exceedingly Imall, as to equallize, if not to be much Imaller then the clew of the Silk-worm, elpe- cially in thinnelSj yet the differences between the figures of the confti- tuting filaments are fo great, and their fubftances fo various, that whereas
C thole
I
6
Micrographia.
thofe of the Silk^ arc fmall^round^ hard^ tranjparent, and to their bignefs proportionably ftiff:, fo as each filament preferves its proper Figure^ and confequently its vivid reflection intire, though twifted into a thread, if not too hard 5 thofe of Flax are flat^ limber^fofter^znd lefl tranflarent^und in twifiing into a thread they joyn,and lie fo clofe together,as to lofe their own, and deftroy each others particular refledlions. There Teems there- fore three Particulars very requifite to make the To dreft Flax appear Silk alfo when fpun into threads. Firft, that the fubftance of it fhould be made more clear and tranjparent^ Flax retaining in it a kind of opacating brown, or yellow 5 and the parts of the whitefi: kind I have yetobferv'd with the Microfcope appearing white, like flaw’d Horn or Glafs, rather then clear, like clear Horn or Glafi. Next that, the filaments fhould each of them be rounded^ if that could be done, which yet is not fo very necefi fary, if the firfl: be perform’d, and this third, which is, that each of the fmall filaments be flifned-^ for though they be Iquare, or flat, provided they be tranfl^arent and ftiff, much the fame appearances mufl: neceflarily follow. Now, though I have not yet made trial, yet I doubt not, but that both thefe proprieties may be alfo induc’d upoil the FJax,and perhaps too by one and the fame Expedient, which fome trials may quickly inform any ingenious attempter of, who from the ufe and profit of fuch an Invention, may find iufficient argument to be prompted to fuch Inquiries. As for the tenacity of the fubffance of Flax, out of which the thread is made, it leems much inferiour to that of Silk, the one being a vegetable^ the other an animal fubftance. And whether it proceed from the better con- coction, or the more homogeneous conftitution of animal fubftances above thofe of vegetables^ I do not here determine 3 yet fince I ge- nerally find, that vegetable fubftances do not equalize the tenacity of ani-- mal^ nor thefe the tenacity of fome purified mineral fubftances 5 I am’ very apt to think, that the tenacity of bodies does not proceed from the hamousy or hooked particles, as the Epicureans^ and fome modern Fhilofo- phers have imagin’d , but from the more exaCt congruity of the confti- tuent parts, which are contiguous to each other, and fb bulky, as not to be eafily feparated, or fhatter’d, by any fmall pulls or concufiion of heat.
Obferv. 1 V, Of fine waled Silk:, or Tajfety,
Schtm, 3. Fig. I.
THis is the appearance of a piece of very fine Taffety-riband in the bigger magnifying Glafs, which you fee exhibits it like a very con- venient fubftance to make Bed-matts,or Door-matts of,or to ferve for Bee- hives, Corn-fcuttleSjChairs. or Corn-tubs,it being not unlike that kind of work, wherewith in many parts in England^ they make fuch Utenfils of Straw,a little wreathed,and bound together with thongs of Brambles. For in this Contexture, each little filament, fiber, or clew of the Silk-worm, feera’d about the bignefs of an ordinary Straw, as appears by the little ir- regular
i
::i
an:ni
M I C Pv O G R A P H i A.
regular piecesj^ b^c ef 5 The Warp^^ov the thread that ran croffing the
Ribandjappear’d like afingle Rope of an Inch Diameter; but the ^oof, or the thread that ran the length of the Riband;, appear’d not half lb big. Each Inch of fix-peny-broad Riband appearing no Ids then a piece of Matting Inch and half thick, and twelve foot fqiiare ; a few yards of this, would be enough to floor the long Gallery of the Loare at Pariri But to return to our piece of Riband : It affords us a not unpleafanfob- jed, appearing like a bundle, or wreath, of very clear and tranlparenc Cylinders’ll the Silk be white, and curiouffy ting’d ; if it be colour’d,each of thole Imall homey Cylinders affording in fome place or other of them, as vivid a refledion, as if it had been lent from a Cylind.er of Glafs or Horna In-lb-much, that the refledions of Red, appear’d as if coming from lb many GranaHs^ or Rubies. The lovelinels of the colours of Silks above thofe of hairy Stuffs, or Linnen,confifting.as I elfe-where intimate,chiefly in the tranfparency, and vivid refledions from the Concave.pr inner furface of the tran^arent Cylinder^ as are allb the colours of Precious Stones ; for moft of the refledions from each of thele Cylinders^ come from the Concave furface of the air, which is as ’twere the foil that incompaffes the Cylinder. The colours with which each ofthefe Cylinders are ting’d, leem partly to be fuperheial, and flicking to the out-lides of them ; and partly, to be imbib’d, or funck into the fubffance of them ; for Silk, feeming to be little elfe then a dried thread of Glew, may be fuppos’d to be very eafily relaxt,and lbftened,by being fteepedin warm, nay in cold,ifpene» trant, juyees or liquors. And thereby thofe tindures, though they tinge perhaps but a fmail part of the fubffance, yet being fo highly impregnated with the colour, as to be almoff black with it, may leave an impreffion ftrong enough to exhibite the delir’d colour. A pretty kinde of artifi- cial Stuff I have feen, looking almoff like tranfparent Parchment, Horn, or Ifing-glals, and perhaps Ibme fuch thing it may be made of, which be- ing tranfparent, and of a glutinous nature, and eafily mollified by keep- ing in water, as I found upon trial, had imbib’d, and did remain ting’d with a great variety of very vivid colours, and to the naked eye, it look’d very like the fubffance of the Silk, And I have often thought, that pro- bably there might be a way found out, to make an artificial glutinous compofition, much refembling, if not full as good, nay better, then that ExcrementjOr whatever other fubffance it be out of which, the Silk-worm wire-draws his clew. If fuch a compofition were found, it were certain- ly an eafie matter to find very quick ways of drawing it out into fmall wires for ule. I need not mention the ufe of fuch an Invention,nor the be- nefit that is likely to accrue to the finder,they being fufficiently obvious* This hint therefore, may, I hope, give fome Ingenious inquifitive Perfon an occafion of making fome trials, which if fuccefsfull, I have my aim, and I fuppofe he will have no occafion to be dilpleas’d.
Obfcjrv^. Vi
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Micrographia.
Obferv. V. Of watered Silks^ or Stufs.
Sthem. j. ^I^Herc are but few Artificial things that are worth obfcrviiig with a Microfcope ^ and therefore I (hall (peak but briefly concerning them. For the Productions of art are fuch rude mif-(hapen things, that when view’d with a Microfcope ^therc is little elfe obfervable,but their deformity. The moft curious Carvings appearing no better then thole rude Ruffian Images we find mention’d in Purchas^ where three notches at the end of a Stick, (food for a face. And the mod: fmooth and burnilh’d furfaces appear moft rough and unpolilht ; So that my firft Realbn why I fhall add but a few obfervations of them, is, their mif-lhapen form ^ and the next, is their u(cle(sne(s. For why fhould we trouble our (elves in the examination of that form or (hape (which is all we are able to reach with a Microfiope') which we know was defign’d for no higher a u(e, then what we were able tb view with our naked eye ? Why (hould we endeavour to difeover myfteries in that which has no (iich thing in it } And like Rabbins find out Caballifms^ and £nigmts in the Figure, and placing of Letters, where no liich thing lies hid : whereas in forms there are (bme fo fmall, and
(b curious,and their defign’d bufinefs (b far remov’d beyond the reach of our fight, that the more we magnify the objeCf, the more excellencies and myfteries do appear 5 And the more we dilcover the imperfeClions of our fenfes, and the Omnipotency and Infinite perfections of the great Crea- tour. I (hall therefore onely add one or two Obfervations more of artifi- cial things, and then come to the Treaty concerning (uch matters as are the Productions of a more curious Workman. One of thelc^fhall be that of a piece of water’d Silk, reprelented in thelecond Figure of the third Scheme^2iS\t appear’d through the leaft magnifying Glals. A B. fignifying the long way of the Stufr,and C D the broad way. This Stuff, if the right fide of it be looked upon, appears to the naked eye, all over (b waved, undulated, or grain’d, with a curious, though irregular variety of brigh- ter and darker parts, that it adds no fmall gracefulnels to theGlolsofir. It is fo known a propriety, that it needs but little explication, but it is ob- fervable, which perhaps everyone has not confidered, that thole parts which appear the darker part of the wave, in one pofitionto the light, in another appears the lighter, and the contrary^and by this means the undu- lations become tranfient, and in a continual change,according as the po- fition of the parts in refpcCf of the incident beams of light is varied. The realbn of which odd phenomena, to one that has but diligently examin’d it even wdth his naked eye, will be obvious enough. But he that oblerves it with a Microfcope^ may more eafily perceive v/hat this Proteus is, and how it comes to change its (hape. He may very ealily perceive, that it proceeds onely from the variety of the Refle&ions of light, which is caus’d by the various pape of the Particles, or little protuberant parts of the thread that compofe the furface 5 and that thofe parts of the waves that
appear
MiCROGRAPHIAa
appear the brighter. throw towards the eye a multitude of fmall reflexi- ons of light, whereas the darker fcarce aflord any. The reafon of which refledion, the plainly difcovers, as appears by the Figure. In
which you may perceive, that the brighter parts of the lurface confifl: of an abundance of large and Jhrong refleXions, denoted by rf, 4, See.
for the furfaces of thofe threads that run the lot7g way, are by the Mecha- nical proceft of watering, creas'd or af?gkd in another kind of pofture then they were by the weaving : for by the weaving they are onely be^t round the warping threads ^ but by the watering, they are bent with an angle, or elbow, that is in ftead of lying, or being bent round the threads, as in the third Figure, a, a, a, a, a, are about b,b,b Q,b,b reprelenting the ends,as ’twere,of the crofsthreads,they are bent about) they are creas’d, on the top of thofe threads, with an angle, as in the fourth Figure, and that with all imaginable variety 5 fo that, whereas before they refleXed the light onely from one point of the round furface, as about c, c, c, they now when water’d, refleX the beams from more then half the whole fur- fece,as de,de,de, and in other poftures they return no refieXions at all from thofe furfaces. Hence in one pofture they compofe the brighter parts of the waves,in another the darker. And thefe refleXions are alfo varied, according as the particular parts are varioufly bent. The reafon of which creafing we fliall next examine 5 and here we muff fetch our in- formation from the Mechanifra or manner of proceeding in this operation 5 which, as I have been inform’d, is no other then this.
They double all the Stuft that is to be water’d, that is,they creafo it juft through the middle of it, the whole length of the piece, leaving the right fide of the Stuff inward, and placing the two edges, or filvages juft upon one another,and,as near as they can, place the wale fo in the doubling of it, that the wale of the one fide may lie very near parallel, or even with the wale of the other 3 for the nearer that pofture they lie, the greater will the watering appear 5 and the more obliquely, or acrofi to each other they lie, the fmaller are the waves. Their way for folding it for a great wale is thus : they take a Pin,and begin at one fide of the piece in any wale,and fo moving it towards the other fide, thereby direX their hands to the op- pofite ends of the wale, and then, as near as they can, place the two op- pofite ends of the fame wale together, and fo double, or fold the whole piece, repeating this enquiry with a Pin at every yard or two’s diftance through the whole length 5 then they fpririkle it with water,and fold it the longways, placing between every fold a piece of Paftboard, by which means all the wrong fide of the water’d Stuff becomes flat, and with little wales, and the wales on the other fide become the more protuberant j whence the creafings or angular bendings of the wales become the more perfpicuous. Having folded it in this manner,they place it with an inter- jacent Paftboard into an hot Prefs, where it is kept very violently preft, till it be dry and ftiff, by which means, the wales of either contiguous lides leave their own imprefiions upon each other, as is very mani- feft by the fecond Figure, where ’tis obvious enough, that the wale of the piece A B C D runs parallel between the pricked lines ef, ef,ef, and as
D manifeft
lO
Schem, 4,
Micro g r a p h i a.
manifeft to difcern the impreflions upon thefe wales, left by thofe that were preft upon them5which lying not exadly parallel with them, but a lit- tle athwart them , as is denoted by the lines of,<? 0 0 o^gh. gh^gh^ between which the other wales did lie parallehthey are fo varioulIy,and irregular- ly creas’d that being put into that lhape when wet,and kept fo till they be drie, they lb fet each others threads, that the Moldings remain almoft as long as the Stuff lafts.
Hence it may appear to any one that attentively conliders the Figure, why the parts of the wale 4, 4, (hould appear bright ^ and why
the parts />, /», /», fhould appear (hadowed, or dark^ why feme, as (hould appear partly light,and partly dark : the varieties of which reflexions and Ihadows are the only caufe of the appearance of wa- tering in Silks, or any other kind of Stuffs.
From the variety of refleXion, may alfo be deduc’d the caule why a finall breez or gale of wind ruffling the liirface of a fmooth water, makes it appear black , as alfo,on the other fide, why the fmoothing or burnifli- ing the furface of whitened Silver makes it look black 5 and multitudes of other phenomena might hereby be folv’d, which are too many to be here infifted on.
Obferv. VI. Of [mail Glafs Canes,
THat I might be (atisfi’d, whether it were not poflibleto make an Artificial pore as fiftall as any Natural I had yet found, I made fe- veral attemps with final! glajs pipes^ melted in the flame of a Lamp, and then very juddenly drawn out into a great length. And, by that tneans^ without much difeculty, I was able to draw fome almoft as finall as a Cobweb:, which yet, with the AficroJcopC:, I could plainly perceive to be perforated:, both by looking on the euds of it, and by looking on it agamji the light 5 which was much the eajier way to determine whether it were Iblid or perforated 5 for, taking a finall pipeofglafi, and clofing one end of it, then filling it half full 2LV\dho\dmg\t agawjl the lights
I could, by this means, very eafily find what was the clifieriug ajpe& of a Jolid and a perforated piece of glafi 5 and fb eafily diltinguifh, without feeing either end, whether any of glafs I look’d on, were a. Jolid
fiick^:, or a hollow cane. And by this means,! could alfb prefently judge of any finall filament of glafs, whether it were hollow or not^ which would have been exceeding tedious to examine by looking on the end. And many fuch like ways I was fain to make ule of, in the examining of di- vers other particulars related in this Book, which would have been no eafie task to have determined meerly by the more common way of look- ing on, or viewing the ObjeX. For, if we confider firft,the very faint light wherewith the objeX is enlightened, whence many particles zy’' YGZX opacous:, which when more enlightned, appear very lb that I was fain to determine its tranjparency by one glals, and its texture by another Next, the unmanageabknefs of moft Obje^s^ by realbn
of
MlCROGRAPHIAi l£
o£thdtfiialnefiy 5. The difficulty of findihg the defired point, and of placing it fo, as to refied the light conveniently for the Inquiry, Laftly, ones being able to view it but with one eye at once, they will appear no finall obflu0ions^ nor are they eafily removd without many contrivan- ces. But to proceed, I could not find that water, or fbme deeply tingd liquors would in filiall ones rife fo high as one would exped 5 and the highefl I have found it yet rife in any of the pipes I have try’d. Was to 21 inches above the level of the water in the veflel ; for though I found that in the fmall pipes it would nimbly enter at firft, and run about 6 or 7 upwards^ yet I found it then to move upwards^^ that I have not yet had the patience to obferve it above that height of 21 in- ches (and that was in a pretty large Tipe^ in comparifon of thofe I for- merly mentioned , for I could oblerve the progrejs of a very deep tingd liquor in it with my naked eye^ without much trouble 5 whereas many of the other pipes Ycexeio very fmaU.^ thatunlefs in sl convenient pojiure to the light, I could not perceive them :) But ’tis very probable, that a greater patience and ajpduity may difcover the liquors to rife^ at lead to remain fufpcnded.j at heights that I fhould be loath now even to ghefs at, if at lead: thexehe 2Lny proportion kept between the height of the afcending liquor, and the bignefs of the holes of the pipes.
An Attempt for the Explication of this Expertmeni,
My Conjedure, ’That the unequal height of the Jurfaces of the water ^ proceeded from the greater prejjure made upon the water by the Air f without the Pipes ABC, then by that within them ^ I (hall endeavour to confirm from the truth of the two following Propoftions :
The firfl: of which is. That an unequalprefure of the incumbent Air^ will caufe an unequal height in the water s Surfaces.
And the fecond is. That in this experiment there is Juch an unequal prefure.
That the firft is true^ the following Experiment will evince. For if you take any Veflel fo contrived, as that you can at pleafure either in- creafe or diminif the prefure of the Air upon this or that part of the Su- perficies of the water^ the equality of the height of thofe parts will pre- fently h^loji-^ and that part of th.Q Superficies t\nt{\x{i2\nsxhQ greater f ref fire, will be inferior to that which undergoes the lefs. A fit Veflel for thispurpofe, will be an inverted Glafs <S)';?^f/;?, fuch an one as is defer!- bed in the Sixth Figure. For if into it you put Water enough to fill it as high as A B, and gently blow in at £), you fhall deprefs the Superficies and thereby raifexh.^ oppofite Superficies^ to a conjtderable height ^ and by gently Juc king you may produce clean contrary etfeds.
Next, That there is fuch an unequal prefure^ I fball prove &om this, ihat there is a much greater incongruity of Air to Glafs^and fbme other Bodies^ then there is of Water to the fame.
D By
12
Micrographia.
By CongYuity^ I mean a property of a fluid Body^ whereby any part of it is readily united with any other part^ either of it felf or of any other Simi- lar^ fluids or folid body : And by Incongruity a property of a fluids by which it is kindred from uniting with any dijfimilar^fluid^or folid Body.
This laft property, any one that hath been obfervingly converfant about fluid Bodies, cannot be ignorant of. For (not now to mention feveral Chymical Spirits and Oyls^ which will very hardly^ if at all^ be brought to mix with one another ^ inlbmuch that there may be found fome 8 or 9, or more, feveral diftind Liquors, which fwimming one up- on another, will not prefently mix) we need feek no further for Exam- ples of this kind in fluids^ then to obferve the drops of rain falling through the 4/>, and the bubbles of air which are by any means conveyed under the forface of the water 5 or a drop of common Sallet Oyl fwimmingupon water. In all which, and many more examples of this kind that might be enumerated, the incongruity of two fluids is eahly dilcernable. And as for the Congruityox Incongruity of Liquids, with feveral kinds oijirm Bodies, they have long fince been taken notice of, and called by the Names of Drinefs and Moiflure (though thefe two names are not compre- henfivc enough, being commonly ufed to fignifie only the adhering or not adhering of water to fome other folid Bodies)o£ this kind wemay ob- (erve that water will more readily wet Jomc woods then others and that water^ let fall upon a Feather^ the whiter fide of a Colwort^ and fome other leaves. Or upon almofl: any unUuous^ or reftnous {u^erdcies will not at all adhere to them, but eafily tumble ojf fi om them, like a I'olid Bowl 5 whereas, ifdropt upon Linnen, Paper ^ Clay^ green Wood^ 8cc. it will not be taken off, without leaving fome part of it behind adhering to them. So ^ickfllver^ which will very hardly be brought to flicks to any vegeta- ble body^ will readily adhere to, and mingle with, feveral clean metalline bodies.
And that we may the better finde what the caufe of Congruity and Incongruity in bodies is, it will be requifite to confider, Firll:, what is the caufe of fluidnefs 5 And this, I conceive^ to be nothing elfe but a certain pulfe or Jhake oiheat ^ for Heat being nothing elfe but a very bris kjar^d ve- hement agitation of the parts of a body (as I have elfwhere made proba- bable) the parts of a body are thereby made fb loofe from one another, that they eafily move any way^ and become fluid. That I may explain this a little by a grofs Similitude, let us fuppofe a difh of fand fet upon fome body that is very much and fhaken with fome quiche and
firong vibrating motion^as on a Milflone turn’d round upon the under ffone very violently whilfl it is empty^or on a very fl:iffDm«?-head, which is ve- hemently or very nimbly beaten with the Drumfticks. By this means, the fand in the difh, which before lay like a dull and nnadive body, be- comes a iperiedi fluid '■) and ye cannofooner make a hole in it with your finger, but it is immediately //W up again^ and the upper furface of it leveU d. Nor can you bury a light body^ as a piece of Cork under it, but it prefently emerges or fwims as ’twere on the top 3 nor can you lay a on the top of it, as a piece of Lead, but it is immediately buried
in
M, I CROGRAPHIA*
in Sandj and (as^tvvere) finks to the bottom. Nor can you make a hok in the fide of the Difli, but the land (hall run out of it to a levels not an obvious property of a fluid body, as fuch, but this dos imitate 3 and all this meerly caiued by the vehement agitation of the conteining veflel 5 for by this means, each (and becomes to have a vibrative or dancing mo* tion, (b as no other heavier body can reji on it, unlels Jufieind by (bme Other on either fide : Nor will it differ any Body to be beneath it, unlefs it be a heavier then it felfl Another Inftance of the (f range loofening nature of a violent jarring Motion, or a ftrong and nimble vibrative one, we may have from a piece of iron grated on very ftrongly with a file : for if into that a pin be fcrexdd (b firm and hard, that though it has a convenient head to it, yet it can by no means be unfcrevpd by the fin* gers ^ if, I fay, you attempt to unlcrew this whilft grated on by the file^ it will be found to undoe and turn very eafily. The firfl: of thel'e Examples manifefl s, how a body adually divided into fmall parts, becomes a fluidi And the latter manifefts by what means the agitation of heat fo eafily loofens and unties the parts of folid and firm bodies. Nor need we (up* pofe heat to be any thing elfe, befides fuch a motion 5 for fuppofing we could Mechanically produce (uch a one ^«ic^and Jirong enough, we need not fuel to melt a body. Now, that I do not (peak this altogether groundleis, I muft refer the Reader to the Obfervations I have made up- on the (hining fparks of Steel, for there he (hall find that the fame effeds are produced upon fmall chips or parcels of Steel by the flame^ and by a quicks and violent motion ^ and if the body of feel may be thus melted (as I there (hew it may) I think we have little realbn to doubt that al* moft any other may not al(b. Every Smith can inform one how quickly both his File and the Iron grows hot with filing^ and if you rub almoft any two bodies together, they will do the (ame : And we know, that a fufficient degree of heat caufes fluidity^ in (bme bodies much (bon- er, and in others later 5 that is, the parts of the body of (bme are (b Icoje from one another, and (b unapt to cohere, and (b minute and little, that a very^4// degree of agitation keeps them always in the fate of fluidity. Of this kind, I (iippole, the Mther, that is the medium or fluid body, in which all other bodies do as it were fwim and move 5 and particularly, the Air, which feems nothing elfe but a kind of tinBure or folution of ter- reftrial and aqueous particles into it, and agitated by it, jufl: as
xd\o.tinBureoiCocheneel\% nothing but (bme finer dfloluble parts of that Concrete lick’d up or dijjolvd by the fluid water. And (rom this Notion of it, we may eafily give a more Intelligible reafon how the Air becomes (b capable oi RarefaBion and Condenfation. For, as in tinBures,onQ grain of (bme flrongly tinging fubftance may fenflbly colour (bme hundred thou- fand grains of appropriatedV\cpjLOxs,{o as every drop of it has its proportio- nate (hare, and be fenfibly ting’d, as I have try’d both with Logtoood and Cocheneel : And as fome few grains of Salt is able to infed as
greataquantity,as may befoundby/jr^f^^z^d/zf/^j-, though not (b eafily by the fight or afle 5 (b the Air, which feems to be but as ’twere a tinBure or faline Jubfiance, diJ[olvd and agitated by the fluid and agil A£theryxizy dff
Micrograp hia.
perfe and expand it felf into a vajl Jpace^ if it have room enough, and infed,as it were,every part of that fpace. But, as on the other fide, if there be but Come f erf graws of the liquor, it may extraB all the colour of the tinging fubftance, and may dijjblve all the Salt, and thereby become much more impregnated with thofe fubftances, fo may all the air that luf^ ficed ina rarifyd (iate to fill fome hundred thoufaud fpacesof i^!ther, be compris’d in only one^Mt in a pofition proportionable denfe. And though we have not yet found out fuch firainers for Tinftures and Salts as we have for the Air, being yet unable to feparate them from their diflblving liquors by any kind oifiltre^ without precipitation^ as we are able to fe^ parate the Air from the ^ther by Glafs^ and feveral other bodies. And though we are yet unable and ignorant of the ways of precipitating Air out of the Aither as we can Tindtires, and Salts out of feveral dijjblventsi, yet neither of thefe fceming impojjible from the nature of the things, nor fo improbable but that fome happy future induftry may find out ways to effcd them 5 nay, further, fince we find that Nature does really perform (though by what means we are not certain) both thele adcions, namely, by precipitating the Air in Rain and Dews, and by fopplying the Streams and Rivers of the World with frefh water, flraind through lecret fiib- terraneous Caverns; And fince, that in very many oth.tr proprieties they do fo exaftly feem of the fame nature 5 till further obfervations or tryals do inform us of the contrary^ we may fafely enough conclude them of the fame kind. For it feldom happens that any two natures have fo ma-^ ny properties coincident or the fame, as I have obferv’d Solutions and Air to have, and to be different in the reft. And therefore I think it nei- ther impcjfible^ irrational^ nay nor difficult to be able to prediB what is likgly to happen in other particulars alfo, befides thofo which Obfervation or Experiment have declared thus or thus 5 elpecially, if the circum- fiances that do often very much conduce to the variation of the efiedls be duly tveigh’d and conjiderd. And indeed, were there not a probability of this, our inquiries would be endlefs^ our tryals vain^ and our greateff in* ventions would be nothing but the meer produBs of chance^ and not of Reajbn 5 and, like Mariners in an Ocean, deftitute both of a Compafs and the fight of the Celefiialguids^ we might indeed, by chance^ Steer direBly towards our defired Port, but ’tis a thoufand to one but we mife our aim. But to proceed, we may hence alfo give a plain reafon, how the Air comes to be darkled by clouds^ 6cc. which are nothing but a kind of precipitati* on^ and how thofe precipitations fall down in showrs. Hence alfo could I very eafily, and I think truly, deduce the caufe of the curious (ixangu* lar figures of Snow, and the appearances of Haloes^ d^c. and the ludden thickgiing of the Sky with Clouds, audthe varnfijing and dijappearing of thole Clouds again 5 for all thele things may be very eafily imitated in a glafsof liquor ^\td\ fome iWght Chymical preparations as I have often try’d, and may fomewhere elfe more largely relate, but have not now time to fet them down. But to proceed, there are other bodies that confiftof particles more Crofi^ and of a more apt figure for cohefion^ and this re- quires agitation , fuch, I fup^ofe fermentedvinous
Spirits
M I C ROG R A P H I A»
Spirits, feveral Chjimical Oils, which are much of kin to thofe Spirits, &c< Others yet require 2i greater, as water, and fo others much greater, for al- moft infinite degrees: For, I fuppofe there are very /w bodies in the world that may not be made alicptatemis fluid, by [ome or other degree of agitation or heat.
" Having therefore in fhort fet down my Notioil of a Fluid body, I cotne in the next place to confider what Congruity is 5 and this, as I faid before, being a Relative property of a fluid, whereby it may be faid to be like or ttnlike to this or that other body, whereby it does or does not mix with this or that body. We will again have recourfe to our former Experi- ment, though but a rude one , and here if we mix in the dSHhfeveral kiisdi of lands, fome oi bigger, others of lefs and finer bulks, we fhall find that by the agitation the fine /and will eje& and throw out of it felf all thofe bulks of {m2i\\jiones and the like, and thofe will be toge-
ther all into one place 5 and if there be other bodies in it of other natures, thofe alfb will hcfeparatedmio a place by themfelves, and unitedoxtum- hledw^ together. And though this do not come up to the higheji proper- ty of Congruity, which is a Coh^fion of the parts of the fluid together, or a kind of attraBion and tenacity, yet this does as ’twere fi?adow it out, and fbmewhat relemble it, for juft after the fame manner, I fuppofe the of heat to agitatet\iQ fmall parcels of matter, and thofe that are of a like bignef, 2X\d figure, and matter, will hold, or dance together, and thofe which are of a differing kind will be thruji or Jhovd oUt from be- tween them^ for particles that are all fimilar, willj like fb mzny equal ntufical firings equally firetcht, vibrate together in a kind of Harmony or nnifon , whereas others that are diffimilar, upon what account fbever,un- lefsthe difproportion be othcrwife counter-ballanc’d, will, like fbmany firings out of tune to thofe unlfons, though they have the fame agitating pulfe, yet make quite diff^ering kinds of vibrations and repercuffions, fb that though they may be both mov’d,yet are their vibrations {o dijferent,and fo untun d, as twere to each other, that they crofs and jar againft each other, and confequently, cannot agree together, but fly back^itom each other to their fimilar particles. Now, to give you an inftance how the difproportion of fome bodies in one refpeft, may be counter-ballunc d by a contrary difproportion of the fame body in another refped, whence we find that the fubtil vinous Jpirit is congruous, or does readily mix with wa- ter, which in many properties is of a very differing nature, we may con- fider that a unifon may be made either by two firings of the fame bignefs, length, and tenfion, or by two firings of the fame bignefi, but of differing length,zr\d 2l contrary differing tenfion', or fiy. by two firings of unequal length and bignefi, and of a differing tenfion, or of equal length, and diffe- ring bignefs and tenfion, and leveral other flich varieties. To which three properties in firings, will correfpond three proprieties alfo in find, or the particles of bodies, their Matter or Subfiance, their Figure or shape, and their Body or Bulk. And from the varieties of thefe three, may arife in- finite varieties in fluid bodies, though all agitated by theyS^ze pulfioxvi- brative motion. And there may be as many ways of making Harmonies
Micrographia.
and Difcords with thcfe, as there may be with mujical firings. Having
therefore Icen what is the caufe of Congruity or Incongruity, thofe rela- tive properties of fluids, we may, from what has been laid, very eafily collect, what is the of thofe Relative proprieties alfo between flu^
id bodies andjolid ^ for lince all bodies confift of particles of fuch a Sub- fiance^ Figure^ and Bulkj) but in Ibme they are united together more firm- ly then to be loofined from each other by every vibrattve motion (though I imagine that there is nobody in the world, but that Ibme degree of a- gitation may, as I hinted before, agitate and loolcn the particles fo as to make them fluid) thole cohering particles may vibrate in the fame man- ner almofl: as thofe that are loofe and become unijbns or difcords^ as I may lb fpeak, to them. Nowthatthe/?^r/j-of all though never
fb folid^ do yet vibrate^ I think we need go no fnrther for proof, then that ^/('bodies have Ibme of in them, and that there has not
been yet found any thing perfeidly cold: Nor can I believe indeed that there is any fuch thing in Nature, as a body whofe particles are at or lazy and unaBive in the great Theatre of the Worlds it being quite contrary to the grand Oeconomy of the Univerle. We fee therefore what is the rea- fon of the Jympathy or uniting of fome bodies together, and ol the anti- pathy or flight of others from each other : For Congruity feems nothing elfe but a Sympathy^ and Incongruity an Antipathy of bodies ^ hence fimi- lar hoddes once united w\\\ not eafily part and dijfimilar bodies once difi joyndwill not eafily unite again ; from hence may be very eafily deduc'd the realbn of ihe/ujpenfion ob water and ^ickfilver above their ufual fia- //<?»,asl lhall more at large anon fhew.
Thele properties therefore (alwayes the concomitants of fluid bodies) produce thele following vihhle Efietls .*
Firfi:, They unite the parts of a fluid to its fimilar Solid, or keep them feparate from its dijjimilar. Hence ^ickfilver will (as we noted before) liick^ to Gokf Silver^ Tin^ Leadfi>i.c. and unite with them : but roul off from Woodj Stone^ Glafs^ 8cc. if never lb little feituated out of its horizontal le^ veli^ and water that will wet fait and dijjblve it, will firp off from Tallow^ or the like, without at all adhering ^ as it may likewife be obferved to do upon a dufiy luperficies. And next they caule the parts of homogene- al fluid bodies readily to adhere together and mix^ and of heterogenealyo be exceeding averfe thereunto. Hence we find, that two fmall drops of water ^ on any luperficies they can roul on, will, if they chance to touch each other, readily unite and mix into one drop : The like may be ob- fexvedWithtwohtnaWBowlsob ^ithcfdver xi^on a Table or Glafs, pro- vided their furfaces be not ^ and with two drops of oy upon fair water, (fic. And further, water put unto wine^falt water ^ vinegar^ fii^B of or the like, does immediately (efpecially if they be fhaken to- gether) dijperje it lelf all over them. Hence, on the contrary, we allb find, that Oyl ofTartarp^onxed upon g^ickcftlver^ and Spirit of Wine on that Oyf and Oyl of Turpentine on that Spirit^ and Air upon that C^/,though they beftopt clofely up into a Bottle, and fijaken. never fo much, they will by no means long fufter any of tlieir bigger parts to be united or in- cluded
MiCROGRAP HiA.
eluded within any of the ether Liquors'(by which recited Liquors, may he plainly enough reprefented the four Peripatetical Elements^ and the more fubtil j¥.ther above all.) F rom this property’tis, that a drop of vpater does not mingle with, or vanilh into Air^ but is driven (by that Fluid equally protruding it on every fide) andforc’t into as little afpace as it can pofi fibly be contained in, namely, into a RQund Globule. So likewife a lit” tie Air blown under the rvater^ is united or thruft into a ^bble by the ambient water. And a parcel of ^ickcfdver enclofed with Air^ Water ^ or almoft any other Liquor., informed into a round Ball.
Now the caufe why all thefe included Fluids, newly mentioned, or as many others as are wholly included within a heterogeneous fiuid, are not exaH ly oi 2. Spherical Figure (feeing that if caufedby thefe Principles only, it could be of no other) muft proceed from fome other kind of preffure againfi: the two oppofite flatted fides. This ad.ventiuons or acci- dental prej^ure may proceed from divers taujes, and accordingly muft di- the Figure of the included heterogeneous fluid : For feeing that a body may be included either with a fluid only, or only with a folid , or partly with a fluid, and partly with a folid, or partly with one fluid, and partly with another 5 there will be found a very great variety of the ter- minating Jurfaces, much differing from a Spherical^ according to the vari- ous refiftance or preffure that belongs to each of thefe encompaffing bo- dies.
Which Properties may in general be deduced from tv/o heads , viz. Motion^ and ReU. For, either this Globular Figure is altered by a natu- tal Motion^ fuch as is Gravity 5 or a violent ^ fuch as is any accidental motion of the fluids, as we fee in the itcind ruffling up the water, and the purlings of Streams^ 2nd foaming oiCatarraBs^ and the like. Or thirdly. By the Refl^ Firmnefs 2nd Stability oi the ambient Solid. For if the including Solidbo of an angular or any other irregular Form, the included fluid will be near of the likeyis a Pint-r^^t full of water ^ot a Bladder full of Air. And next, if the including or included fluid have a greater one than
another,then will the globular Formbedepreft into 2n Elliptico-fpherical ; As if, for example, we fuppofethe Circle A B C D^in the fourth Figure.^ toxe^xe(ent2drop of roater, g^ick^filver., or the like, included with the Air or the like , which fuppohng there were no gravity at all in either of the fluids^ or that the contained 2nd containingwete of the fame weighty would be equally comprefl into anexadly fphericalhodj ( the ambient fluid forcing equally againft every fide of it. ) But fuppofing either a greater^r4«/z>j' in the included, by realbn whereof the parts of it being preflfwm A towards 5, and thereby the whole put into motion ^ and that motionhem^ kindred by the refiflance o£ the Jubjacent parts of the ambient, the globular Figure A D B C will be depreji into the Elliptico- jphericaly E G F H. For the fide ^ h detruded to E oy the Gravity , and B to F by the refiflance of the fiibjacent medium : and therefore C muft neceffarily be thruff to G5 and D to H. Or elle, fuppofing a greater ty in the ambient^ by whole more then oxddn2iy preflure againft the under lide of the included globule 5 B will be forced to F, and by its refiftance of
E the
Ml CROGRAPHiA.
the motion upwards ^ the fide A will be depreji to £, and therefore C being thruft to G and D to H 5 the globular Figure by this means alfo will be made an Elliptico-fpherical. Next if a fluid be included partly with one^ and partly with another fluid, it will be found to be fhaped diverjly , ac- cording to the proportion of the gravity and incongruity of the 3 jlftids one to another : As in the fecond Figure^ let the upper M AfMbe Air^the middle L M N 0 be common (^/, the lower 0 0 0 be fVater^ the Oyl will be form’d, not into a Figure, fuch as is reprefented by the
pricked Line^ but into fuch a Figure as L M N O, whole fide L M N will be of a flatter £//7^/;^vt/Figure, by reafon of the great difproportion between the Gravity of Oyl and Air^ and the fide L O M of a rounder^ bccaufe of the fmaller difference between the weight of Oyl and Water, globular Figure will be changed,if the ambient be partly fluid and partly folid. And here the termination of the incompafled fluid to- wards the incompafling is fhap’d according to the proportion of the con- fruity or incongruity of the fluids to the folids , and of the gravity and incongruity of the fluids one to another. Asfuppofethe fubjacent me^ dium that hinders an included fluids dcfcent,be a jblid , as let K I, in the fourth Figure^ reprefent the fmooth fuperficies of a Table 5 E G F H, a parcel of running Mercury 5 the fide G F H will be more flatted , ac- cording to the proportion of the incongruity of the Mercury and Air to the ^£<?<?d,and oi the gravity of Mercury z.n6. Air one to another 3 The fide G E H will likewife be a little more depreft by reafon the fubjacent parts are now at refl:,which were before in motion.
Orflirther in the/^7r^£;|g^»r^, let A I L D reprefont an including lid medium of a cylindrical fhape ( as fuppofe a fmall Glafs Jar ) Let F G E M M reprefont a contain’d fluid, as water 5 this towards the bot- tom and fides, is figured according to the concavity of the Glafs : But its upper Surface, ( which by reafon of its gravity, ( not confidering at all the Air above it, and fo neither the congruity or incongruity of either of them to the Glafs ) fhould be terminated by part of a Sphere whofo dia- meter fhould be the fame with that of the earth, which to our fonfo would appear a ffraight Line, as F G E, Or which by reafon of its 'having a greater congruity to Glals than Air has, ( not confidering its Gravity ) would be thruft into 2. concave Sphere, asC H B, whofo diameter would be the fame with that of the concavity of the Veflel : ) Its upper Surface, I fay, by reafon of its having a greater gravity then the Air, and having likewifo a greater congruity to Glals then the Air has, is terminated, by a concave Elliptico-JphericalF'igure, as C KB. For by its congruity it eafily conforms it fol^ and adheres to the Glafs, and conftitutes as it were one containing body with it, and therefore fhould thruft the contained Air on that fide it touches it,into a JphericalFigure, as B H C, but the motion of Gravity depreffing a little the Corners B and C, reduces it into the afbre- faid Figure C K B. Now that it is the greater congruity of one of the two contiguous fluids, then oi the other, to the containing y^/zW, that caufos the feparating furfaces to be thus or thus figured ; And that it is not be- caufo this or that figurated furface is more proper, natural, or peculiar to
Micrograp hi a.
one of thefe fluid bodies^then to the other, will appear from this 5 that the fame fluids will by being put intodifieririgj^/z<j/j- , change their jhrfaces. For the lame water , which in a Glals or wooden Vefl'el will have a con- cave furface upwards,and will rife higher in a fmaller then a greater Pipe, the lame water, I fay, in the fame Pipes greafed over or oyled, will pro- duce quite contrary eflefts 5 for it will have ^.protuberant and ront/ex fur- face upwards, and will not rife fo high in lmall, as in bigger Pipes : Nay, in the very fame folid Veflel - you may make the very fame two contigu- ous Liquids to alter their Surfaces 5 for taking a Imall Wine-glafs,or fuch like Veflel, and pouring water gently into it, you lhall perceive the jur~ face of thev/ater all the way concave^ till it rile even with the top^ when you lhall find it if you gently and carefully pour in more ) to grow VQxy protuberant and convex 5 the realbn of which is plain , for that the fl?lid lides of the containing body are no longer extended , to which the water does more readily adhere then the air 5 but it is henceforth to be included with air, which would reduce it into a hemifphere^ but by reafon of its gravity^ it is flatted into an Oval. Quicksilver alfo which to Glop is more incongruous then Air ( and thereby being put into a Glafs-pipe^ will not adhere to it, but by the more congruous air will be forced to have a y tty protuberant llirface, and to rile higher in a greater then a leflef Pipe 3 this Qjiicksilver to clean Metal, efpecially to Gold,Si her, Tin, Lead, &c. Iron excepted,is more congruous then Air , and will not only ftick to it,but have a concave Surface like water, and rife higher in a lefs, then in a greater Pipe*
In all thefe Examples it is evident , that there is an extraordinary and adventitious force, by which the Figure of the contained hetero- geneous fluid is altered 5 neither can it be imagined, how it Ihoiild other- wife be of any other Figure then Globular : For being by the heterogene- ous fluid tc^aWy protruded every way,whatfoever part is protuberant, will be thereby depreji. From thiscaufeit is, that in its efieds it does very much refemble a round Spring fluch as a Hoop.) For as in a round Spring there is required an additional prejjure againft two oppolite lides , to re- duce it into an OWForm, or to force it in between the lides of a Hole, whole Diameter is lefs then that of the Spring, there muft be a conlidera- ble force or protruflon againft the concave or inner lide of the Spring 5 So to alter this Jp^erzc^z/conftituticn of an included fluid body , there is re- quired more preftiire againft oppolite lides to reduce it into an Oval', and, to prels it into an Hole lefs in Diameter then it felf, it requires a greater: pro- truflon againft all the other lides. What degrees of force are requilit6 to reduce them into longer and longer Ovals , or to prefs them into lefs anA\e{s holes, I have not yet experimentally calculated ^ but thus much by experiment I find in general , that there is alwayes required a greater prefliire to dole them into longer Ovals , or protude them into Imaller holes. The neceflity and realbn of this, were it requilite,! could ea lily ex- plain : but being not fo neceflary , and requiring more room and time then I have for it at prefent , I fliall here omit it , and proceed to Ihew, that this may be prelently found true, if Experiment be made with a
E 2 rojfnd
Micrographia.
rmnd Spring ( the way of making which trials is obvious ) And
with the fluid bodies of Mercury^ Air^ &c^ the way of trying which, will be fomewhat more difficult 5 and therefore I (hall in brief defcribe it. He therefore that would try with Air , mufl: firft be provided of a Glafs-pipe, made of the lhape of that in the fifth Figure , whereof the fide A B, re- prefcnts a ftraight Tubeoi about three foot long, C,reprefents another part of it,which confifts of a round Bubble 5 lb ordered,that there is left a pajjage ox hole at the top , into which may be faftened with cement leveral fmall Pipes of determinate cylindrical cavities : as let the hol/oto of
F.
G.
H.
I.
K.
L.
M. _,
r
> be
1.
4
X
6
X
s
X I a
>
A
*4
i
3»
of an inch.
There may be added as many more , as the Experimenter lhall think lif^ with holes continually decreafing by known quantities, fo far as his fenfes arc able to help him , I fay, lb far, becaufe there may be made Pipes fo (mall that it will be impolTible to perceive the perforation with ones na- ked eye, though by the help of a Microfeope, it may eafily enough be per- ceived ; Nay, I have made a Pipe perforated from end to end, fo fmall, that with my naked eye I could very hardly fee the body of it, inlbmuch that I have been able to knit it up into a knot without breaking : And more accurately examining one with ray Microfiope, I found it not lb big as a fixteenthpart of one of the Imaller hairs of my head which was of the fmaller and finer Ibrt of hair, fo that lixteen of thefe Pipes bound fag- got-wile together, would but have equalized one Angle hair, how Imall therefore mufl: its perforation be ? Ft appearing to me through the Micros- fcope to be a proportionably thickfided Pipe.
To proceed then, for the trial of the Experiment , the Experimenter mufl place the lube A B, perpendicular, and fill the Pipe F ( cemented in- to the hole E ) with water, but leave the bubble C full of Air^ and then gently pouring in water into the Pipe A B, he mufl oblerve diligently how high the water will rife in it before it protrude the bubble of Air C, through the narrow pallage of F, and denote exadly the height of the Cylinder of water , then cementing in a fecond Pipe as G, and filling it with water ^ he may proceed as with the former , denoting likewile the height of the of water , able to protrude the C through
the paflage of G, the like may he do with the next Pipe^zndi the next,c^c. as far as he is able ; then comparing the leveral heights of the Cylinders^ with the leveral through which each Cylinder did force the f ha- ving due regard to the Cylinders of water in t\io fuiddlTubes) it will be very eafie to determine, what force is requifite to prels the Air in- to luch and luch#* hole^ or (to apply it to our prelent experiment J
how
M I C R O G R A P H I A. 21
how much of the preflure of the Jir is taken off by its ingrefsinto fmal- ler and fmaller holes. From the application of which to theentririgof the Air into the bigger of th^VeJJel^ and into the fmaller of the Pipe^ we fhall clearly find, that there is a greater preffure of the air upoti the water in the Vejjelor: greater pipe, then there is upon that in the leffer pipe: For fincethe preflure of the air every way is found to be equal, that is, as much as is able to prefs up and fuftain a Cylinder of gpuicksiher of two foot and a half high, ot thereabouts j And fince of this preflure fo many more degrees are required to force the Air into a fmaller then into a greater hole that is full of a more congruous fluid. And laftly, fince thofe degrees that are requifite to prefs it in, are thereby taken off from the Air within , and the Air within left with fo many degrees of preflure lefs then the Air without 5 it will follow, that the Air in the lefs Tube or pipe , will have lefs preflure againft the fuperficies of tht tvater therein, then the Air in the bigger : which was the minor Propofition to be proved.
The Conclufion therefore will neceflarily follow, viz. That this une^ qnalprefsiire of the Air caufed by its ingref into unequal holes, is a caufe fuffi- dent to produce this effeCl , without the help of any other concurrent \ and therefore is probably the principal (if not the only) caufe of thefe Vh^no- mena. ■ ^
This therefore being thus explained, there will be ^wtrsPheenometta explicable thereby, as, the riling of Liquors in a Fibre, the rifing of Spirit of Wine, Oyl, melted Tallow, &c. in the Week^ of a Lamp, ( though made of fmall Wire, Threeds of Asbeflus, Strings of Glafs, or the like ) the rifing of Liquors in a Spunge, piece of Bread,Sand, d^c. perhaps alfo the afeend-^ ing of the Sap in Trees and Plants, through their fmall, and fbme of them imperceptible pores, (of which I have faid more, on another occafion ) at leaft the palling of it out of the earth into their roots. And indeed up- on the confideration of this Principle, multitudes of other ufes of it oc- curred to me, which I have not yet fo well examined and digefted as to propound for Axioms, but only as ^erics ^ndConje^tures which may forve as hints toward fome further difeoveries.
As firfl, Upon the confideration of the congruity eniA incongruity of Bo- dies,as to touch, I found alfo the like congruity and incongruity Q if I may fo fpeak ) as to the Travfmitting of the Raies of Light ; For as in this re- gard,f not now to mention other Liquors ) feems, nearer of affini- ty to Claf^ then ^z>,and Air then g^mcksilver : whence an oblique Ray otit of Glafs, will pafs into water with very refraction from the perpendi^
cular, but none out of Glafs into Air, excepting a dire&, will pafs without a very great refraction from the perpendicular, nay any oblique Ray un- der thirty degrees, will not be admitted into the Air at all. And ^fo^- will neither admit oblique or direct, butrefledsall 5 feeming,as to the tranfmitting of the Raies of Light , to be of a quite differing confli- tution,from that of Air, Water, Glafs, dAc. and to refemble mofl: thofe opa- cousand ftrong refleding bodies of Metals ; So alfo asto the property of cohefion or congruity , Water feems to keep the fame order , being
more
22
Micrographia.
more congruous to Glafs then Air , and Air then Quickfilver.
A Second thing ( which was hinted to me, by the confideration of the included fluids globular form , cauled by the protrufion of the ambient heterogeneous fluid J was, whether the Vh£n0me?7a of gravity might not by this means be explained,by fuppofing the Globe of Earth, Water, and Aar to be included with a jluid^ heterogeneous to all and each of them, ib fubtil 3 as not only to be every where inter]} erfed through the Air^ ("or rather the air through it J but to pervade the bodies of Glafs , and even the clofejl Metals^ by which means it may endeavour to detrude all earth- ly bodies as far from it as it can 5 and partly thereby ,and partly by other of its properties may move them towards the Center of the Earth. Now that there is Ibme foch fluid,I could produce many Experiments and Rea- Ibns , that do leem to prove it ; But becaufe it would ask fome time and room to fet them down and explain them, and toconfiderandanfwer all the Objedions f many whereof I forefee J thatmay bealledged againfl: it 5 1 (hall at prelent proceed to other ^er/(e/,contenting my lelf to have here only given a hint of what I may lay more ellwhere.
A Third ^erj/ then was , Whether the heterogeneity of the ambient fluid may not be accounted a fecondary canfe of the roundnefs or globular formoi tht greater bodies the world,fuch as are thole of th& Sun^Stars,
and Planets^ the fubfance o£ each ofwhich feems altogether ous to the circum-ambient fluid <cther } And of this I lhall fay more in the Oblervation of the Moon.
A Fourth was. Whether the globular form the fmaller parcels o£
matter, here upon the Earthy as that of Fruits^ Pebbles^ or Flints ,
( which feem to have been a Liquor at firfl: ) may not be cauled by the heterogeneous ambient fuid. For thus we fee that melted will be naturally formed into a round Figure fo likewife any fmall Parcel of any fufhle body , if it be perfedly encloled by the Air , will be driven into a globular Form ^ and,when cold, will be found a folid Ball. This is plainly enough manifefted to us by their way of making fjot with the drops of Lead’-i which being a very pretty curiolity^and known but to a very few, and having the liberty of publilhing it granted me, by dmt Eminent Vir- tuofo Sir Robert Moray , who brought in this Account of it to the Royal So- have here tranferibed and inlerted.
To make fmall fhoc of different fizes ; Communicated by his Highnefs P, R,
TAke Lead out cf the Pig what quantity you pleafe^ melt it down^ fiir and clear it with an iron Ladle , gathering together the blackijh farts that fwim at tof like [cum^ and when you fee the co- lour of the clear Lead to begreerufljfjut no fooner^firew ufonit Auri-
pigmentum
2
M I C R O G R A P H I A.
pigmentum porvdered according to the quantity of Lead^ about much as will lye upon a half Crown piece will fe'rvefor eighteen or twenty pound weight of fome forts of Lead ; others will require more^ or lefi. After the Auripigmentum is put in^ftir the Leadwell^ and the Auripigmentum will fame: when the fame is over ^ take out fome of the Lead in a Ladle having a lip or notch in the brim for conveni- ent pouring out of the Lead^and being well warmed amongfl the melted Lead^ and with a flick make fome fingle drops of Lead trickje out of the Ladle into water in a Glafs ^ which if they fall to be round arid without tails^ there ^ Auripigmentum enough put i% and the temper of the heat is rights otherwife put in more. Then lay two bars cf Iron or fome more proper Iron-.oolmadeon purpofe) upon a Fail of' wa- ter ^and place upon them a round Plate of Copper ^ of the fize and figure cf an ordinary large Pewter or Silver Trencher^ the hollow whereof is to he about three inches over , the bottom lower then the brims about half an inch^ pierced with thirty^ forty ^ or more fmall holes\ the fmaller the holes are^ the fmaller the ff:ot willbe\ and the brim is to be thicker then the bottom^to conferve the heat the better.
The bottom of the Trencher being fome four inches diflant frumthe water in the Pail Jay upon it fom,e burning Coles^to keep the Lead melt- ed upon it. Then with the hot Ladle take L.ead off the Pot where it flands melted^ and pour it foftly upon the burning Coles over the bottom cf theTrencher^ and it willimmediately run through the holes into the water in fmall round drops. Thus pour on new Lead flill as faflas h runs through the Trencher till all be done ; blowing now and then the Coles with hand-Bellows^ when the Lead in the Trencher cools fo as to flop from running,
Whilfl one pours on the Lead.^ another mufl^ with another Ladle^ thrufled four or five inches under water in the Pdil^ catch from time to time fome (f the fhot^as it drops down^ to fee the fize of it^and whether there he any faults in it. The greatefi care is to keep the Lead upon the Trencher in the right degree of heat ; if it be too cool , it will not run through the Trencher^ though it fland melted upon it ; and this is to
24 M 1 C R O G R A P H I A.
h helped by blowing the Coals a little , or pouring on new Lead that k hotter : hut the cooler the Lead^he larger the Shot‘s and the hotter ^he fmaller ; when it k too hot^ the drops will crack and fly ; then you muji flop pouring on new Lead^and let it cool ; and fo long 06you ob^ ■ferve the right temper of the heat^ the Lead will conjlantly drop into very round Shot^ without fo much as one with a tail in rnanypounds.
When all k done^take your Shot out of the Pail of water ^ and put it in a Frying-pan over the fire to dry them , which mufl be done warily^ fill Jhahjng them that they m.elt not ; and when they are dry you may feparatethe [mail from the great , in Pearl Sives made of Copper or Lattin let into one another^ into as many fizes as you pleafe. But if you would have your Shot larger then the Trencher makes them , you may do it with a Stick-, making them trickle out of the Ladle^ as hath been faid.
If the Trencher be but toucht a very little when the Lead flops from going through it^ and be not too coolft will drop again y but it k better not to touch it at alL At the melting of the Lead take care that there
be no kind of Oyl^ Greafe^ or the lik^ upon the Pots^ or Ladlesy)r Tren- cher.
The Chief caufe of thk Globular Figure of the Shot^ feems to be the Auripigmentum ; for^ as foon as it k put in among the melted Lead., it lofes its fbining brightnefs , contracting inflantly a grayiflj film or skin upon it., when you fcurn it to make it clean with the Ladle. So that when the Air comes at the falling dr op cf the melted Lead, that skin conflrids them every where equally : but upon what account, and whether thk be the true caufe, k left to further difquifition.
Much after this lame manner, when the Air is exceeding cold through which it pafles, do we find the drops of Rain, falling from the Clouds, congealed into round Hail-ftonesby the freezing Ambient.
To which may be added this other known Experiment, That if you gently let fall a drop of rvater upon fmall fund or dufl^ you (hall find, as it were, an artificial round flone quickly generated. I cannot upon this oc* cafion omit the mentioning of the ftrange kind of Grain , which I have obferved in a fione brought from Kettering in NorthamptonJInre^znd there- fore called by Malbns Kettering-stone , of which fee the Delcription.
Which
Micrographia.
Which brings into my mind what I long fince obferved in the fiery Sparks that are ftruck out of a Steel. For having a great defire to fee what was left behind, after the Spark was gone out, I purpofely ftruck fire over a very white piece of Paper, and obferving diligently where fome confpi- cuous fparks went out , I found a very little black fpot no bigger then the point of a Pin^ which through a Microfcope appeared to be a perfeft- ly round Ball, looking much like a polilht ball of Steel, infomuch that I was able to fee the Image of the window refleded from it. I cannot here ftay ( having done it more fully in another place ) to examine the particular Reafons of it, but fhall only hint, that I imagine it to be fome fiflall parcel of the Steel , which by the violence of the motion of the ftroke ( moft of which feems to be irapreft upon thofe fmall parcels ) is made fo glowing hot, that it is melted into a Vitrumy which by the ambi- ent Air is thruft into the form of a Ball.
A Fifth thing which I thought worth Examination w^as . Whether the motion of all kind of Springs , might not be reduced to the Principle whereby the included heterogeneous fluid feems to be moved , or to that whereby two Solids, as Marbles, or the like, are thruft and kept together by the ambient fluid.
A Sixth thing was,Whether the Rifing and Ebullition of the Water out of Springs and Fountains ( which lie much higher from the Center of the Earth then the Superficies of the Sea, from whence it feems to be derived) may not be explicated by the rifing of Water in a fmaller Pipe .• For the Sea-water being ftrained through the Pores or Crannies of the Earth, is, as it were, included in little Pipes, where the preflure of the Air has not fo great a power to refift its rifing ; But examining this way, and finding in itfeveral difficulties almoft irremovable, I thought upon away that would much more naturally and conceivably explain it , which was by this following Experiment: I took a Claft-Tube, of the form of that delcribed in the fixth Figure, and chilling two heterogeneous fluids ^ fuch as Water and Oyl , I poured in as much Water as filled up the Pipes as high as A B, then putting in fome Oyl into the Tube AC, I depreft the fuperficies A of the Water to E, and B I railed to G, which was not lb highperpendicularly asthefuperficies of the Oyl F, by the fpace F I,> wherefore the proportion of the gravity of thele two Liquors was as GHtoFE.
This Experiment I tried with feveral other Liquors, and particularly with frelh Water and Salt ( which I made by diftolving Salt in warm Water ) which two though they are nothing heterogeneous, yet before they would perfedly mix one with another , I made trial of the Experb ment .* Nay, letting the Tube wherein I tried the Experiment remain for many dayes , I obferved them not to mix 5 but the fuperficies of the frelb was rather more then left elevated above that of the Salt. Now the proportion of the gravity of Sea- water, to that of River- water, accord- ing to Stevinus and Varenius , and as I have fince found pretty true by making trial my felf, is as 4^1045. that is, 46. Ounces of the fait Wa=
"'FK ter
26 Micrographia.
ter will take up no more room then 45. of the frefh. Or reciprocally 45 pints of falt-water weigh as much as 46 of frefli.
But I found the proportion of Brine to frelh Water to be near 13 to 12: Suppofing therefore G H M to reprefent the Sea, and F I the height of the Mountain above the Superficies of the Sea , F M a Cavern in the Earth, beginning at the bottom of the Sea, and terminated at the top of the Mountain, L M the Sand at the bottom , through which the Water is as it were frrained , lb as that the frefher parts are only permitted to tranfude,and the faline kept back 5 if therefore the proportion of G M to F M be as 45 to 46, then may the Cylinder of vSalt-water G M make the Cylinder of Frelh-water to rife as high as E, and to run over at N* I cannot here ftand to examine or confute their Opinion , who make the depth of the Sea, below its Superficies , to be no more perpendicularly meafiired then the height of the Mountains above it ; Tis enough for me to fay, there is no one of thole that have aflerted it , have experiment tally known the perpendicular of either 5 nor lhall I here determine, whe- ther there ma)^ not be many other caules of the leparation of the frefh water from the lalt , as perhaps fome parts of the Earth through which it is to pals , may contain a Salt , that mixing and uniting with the Sea-falt, may precipitate it ^ much after the lame manner as the Alkalizate and Acid Salts mix and precipitate each other in the preparation of Tarta- rum Vitriolatum. I know not alfo whether the exceeding cold (that mull: neceflarily be ) at the bottom of the Water, may not help towards this leparation , for we find , that warm Water is able to dillblve and contain more Salt , then the lame cold 5 infomuch that Brines ftrongly impregnated by heat, if let cool, do fuller much of their Salt to fubfide and cryftallize about the bottom and fides. I know not allb whether the exceeding prefliire of the parts of the Water one againft another, may not keep the Salt from defeending to the very bottom, as finding little or no room to inlert it lelf between thole parts , protruded lb vio- lently together , or elle Iqueeze it upwads into the luperiour parts of the Sea, where it may more eafily obtain room for it felf, amongfi: the parts of the Water, by realbn that there is more heat and lelsprefiure. To this Opinion I was Ibmewhat the more induced by the relations I have met with in Geographical Writers^ of drawing frelh Water from the bot- tom of the Sea , which is llilt above. I cannot now Hand to examine, whether this natural perpetual motion may not artificially be imitated : Nor can I Hand to anfvver the Objedions which may be made againft this my Suppofition ; As, Firfl, How it comes to pafs,that there arc fbmetimes lalt Springs much higher then the Superficies of the Water? And, Se- condly,Why Springs do not run faller and flower, according to the vary- ing height made of the Cylinder of Sea-water, by the ebbing and flow- ing of the Sea ?
As to the Firft, Inlhort, I fay, the frelh Water may receive again a- laline Tincture near the Superficies of the Earth , by palling through fome lalt or elle many of the faline parts of the Sea may be kept
back, though not all.
And
M I C R O G R A P H I Ai
And as to the Second , The fame Spr/f;gm2Ly be fed andfupplyed by divers Caverns, coming from very far diftant parts of the Sea , fo as that it may in one place be high , in another low water 5 and fo by that means the Spring may be equally lupply’d at all times. Or ehe the Cavern may be fo flraight and narrow , that the water not having fo ready and free padage through it^ cannot uponlo (hort and quick mutations of preflure, be able to produce any fenfible effed at fuch a diftance. Befides that, to confirm this hypotkefis^ there are many Examples found in Natural Hijio^ rianspf Springs that do ebb and flow like the Sea : As particuiarlyjthofe recorded by the Learned and after him by Speed^to be found in
this Ijland: One of which^they relate to be on the Top of a Mountain, by the Imall Village Kilkgn in Flintjldre , Maris <cmulus qui Jiatis tempo- ribus fuasevomit reforbct Aquas 5 Which at certain times rifeth and
falleth after the manner of the Sea. A Second in Caermardenpire^ near Caermarden, at a place called Cantred Bichan 5 gmi ( ut fcribit Gi- raldus ) naturali die bis undis deficiens , toties exuberans , marinas imitatur injiabilitates That twice in four and twenty hours ebbing and flowing , relembleth the unftable motions of the Sea. The rh£nOmena of which two may be eafily made out, by fuppofing the Cavern, by which they are fed, to arife from the bottom of the next Sea. A Third, is a Well upon the River Ogmore in Glamorganpire, and near unto Newton, of which Camden relates himfelf to be certificd,by" a Letter from a Learned Friend of his that obfcrved it. Eons abeji hinc, d'c. The Letter is a little too long to be inferted,but the fubftance is this 5 That this Well ebbs and flows quite contrary to the flowing and ebbing of the Sea in thole parts : for his almofl: empty at Full Sea, but full at Low water. This may hap- pen firom the Channel by which it is fupplied , which may come from the bottom of a Sea very remote from thofe parts , and where the Tides are much diflering from thofe of the approximate fhores. A Fourth, lies in Wejimorland, near the River Loder 5 injiar Euripi fapius in die red- procantibus undis fluit refluit , which ebbs and flows many times a day. This may proceed from its being fupplyed from many Channels , coming from feveral parts of the Sea, lying fufliciently diftant alunder to have the times of High-water diflering enough one from the other 5 lb as that whenfoever it lhall be High water oVer any of thofe places, where thele Channels begin, it lhall like wife be fo in the W ell 5 but this is but a liippo- fition.
A Seventh ^ery was. Whether the dijjblution or mixing of feveral bo- dies, whether fluid or folid,with laline or other Liquors, might not partly be attributed to this Principle of the congruity of thofe bodies and their diflolvents } As of Salt in Water,Metals in feveral Menjiruums, Unduous Gums in Oyls, the mixing of Wine and Water, And whether preci- pitation be not partly made from the lame Principle of Incongruity ? I fay partly, becaule there are in Ibme Diflblutions,fome other Caufes con- current.
I lhall laftly make a much more feemingly ftrange and unlikely ^ery j and that is. Whether this Principle, well examined and explained, may
F 2 not
Micrographia.
not be found a co-efficient in the moft confiderable Operations of Na- ture ? As in thofe of Heat^dud Light^and confequently-of Rarefa&ion and Condenfation^ Hardncfs, and Fluidnefs^ Perfpicuity and Opacoufnefs^Refr acti- ons and Colours. &c. NayJ know not whether there may be many things done in Naturc^in which this may not (f befaid to ) have a Finger? This I have in fome other paflages of this Treatife further enquired into and Ihewn, that as well Light as Heat may be caufed by corroJionj'>^\{\ch. is ap- plicable to congruity^dnd confequently all the reft will be but fubfiquents: In the mean time I would not willingly be guilty of that Error the thrice Noble and Learned Vernlam juftly takes notice of, as fuchjand calls PhiloJbphi<e Genus Enipiricum , quod in pancorum Experi mentor urn Angffitjf dF 0 bfcurit ate f undatum efi. For I neither conclude from one fingle Expe- riment,nor are the Experiments I make ufe of all made upon oiie Subjeft : Nor wreft I any Experiment to make it quadrare with any preconceiv’d Notion. But on the contrary , I endeavour to be converfant in divers kinds of Experiments, and all and every one of thole Trials, I make the Standards or Touchftones, by which I try all my former Notions, whether they hold out in weight, and meafurejand touch, &c. For as that Body is no other then a Counterfeit Gold , which wants any one of the Proprie- ties of Gold, fuch as are the Malleablenels, Weight, Colour. Fixtnels in theFire,Indiflblublenels in Aqua fortis yind the like ) though it has all the other , lb will all thofe Notions be found to be falfe and deceitful, that will not undergo all the Trials and Tefts .made of them by Ex^erF meuts. And therefore fuch as will not come up tothedefired Apex of Perfeftion, I rather wholly rejed and take new, then by piecing and patching,endeavour to retain the old, as knowing llich things at beft to be but lame and imperfed. And this courle I learned from Nature 5 whom we find negledful of the old Body, and fuffering its Decaies and Infirmi- ties to remain without repair , and altogether follicitous and careful of perpetuating the Species by new Individuals. And it is certainly the moft likely way to ered a glorious Strudure and Temple to Nature^ llich as Ihe will be found f by any zealous Votary ) to refide in 3 to begin to build a new upon a lure Foundation of Experiments.
But to digrels no further from the confideration of the Vhdenotnena.^ more immediately explicable by this Experiment, we lhall proceed to ftiew. That, as to the riling of Water in a Filtre^ the realbn of it will be manifeft to him, that does take notice,that a Filtre is conftituted of a great number of Imall long Iblid bodies , which lie fo dole together, that the Air in its getting in between them , doth lofe of its preflure that it has a- gainftthe without them, by which means the Water or Liquor not finding fo ftrong a refiftance between them as is able to counter-ballance the preflure on its fuperficies without, is railed upward, till it meet with a pre^re of the Air which is able to hinder it. And as to the Rifing of Oyl, melted Tallow, Spirit of Wine, &c. in the Week of a Candle or Lamp, it is evident, that it differs in nothing from the former, favc only in this , that in a Filtre the Liquor defeends and runs away by another part 3 and in the Week the Liquor is difperfed and carried away by the
“ Flame 3
MiCROGRAPHlA.
Flame 5 fomething there is alcribable to the Heat , for that it may rarifie the more volatil and (pirituous parts of thofe combuftible Liquors, and lb being made lighter then the Air , it may be protruded upwards by that more ponderous fluid body in the Form of Vapours^ but this can be afcribed to the afcenlion of but a very littlcjand moll: likely of that on- ly which afcends without the Week. As for the Riling of it in a Spunge, BreadjCotton.c^c. above the liiperficies of the fubjacent Liquor 5 what has been faid about the Filtre ( if conlidered ) will ealily luggell: a realbii , conlidering that all thefe bodies abound with fmall holes ot pores.
From this fame Prihciple allb ( the unequal prejjkreof the Air gainfi the unequal juperficics of the water ) proceeds the caufe of the ac- cellion orincurlion of any floating body againll: the lidesof the con-» taining Veflel , or the appropinquation of two floating bpdies, as Bubbles^ Corks ^ Sticks:, Straws^ one towards another. As for inftance. Take
a Glafs-)ar, fuch as A B in the leventh Figure^ and filling it pretty near the top with water , thtow into it a fmall round piece of Cork , as C, and plunge it all over in water , that it be wet , fo as that the water may rile up by the fides of it,then placing it any where upon the fuperficies, about an inchjOr one inch and a quarter from any fide, and you fliall perceive it by degrees to make perpendicularly toward the neareft part of the fide, and the nearer it approaches , the fafter to be moved ^ the reafon of which ?h(£nomenon will be found no other then this, that the Air has a greater prefliire againlf the middle of the fuperficies ^ then it hasagainlt thofe parts that approach nearer , and are contiguous to the fides* Now that the preflure is greater , may ( aslfhewed before in the explication of the third Figure ) be evinced from the flatting of the water in the middle, which arifes from the gravity of the under fluid : for fince, as I (hewed before,if there were no gravity in the under fluid^ov that it were equal to that of the upper, the terminating Surface would he: Spherical^ and fince it is the additional preflure of the gravity of water that makes it lb flatjit follows, that the preflure upon the middle muft be greater then towards the fides. Hence the Ball having a ftronger preflure againft that fide of it which relpects the middle of the fuperficies ^ then againft that which refpeds the ^p;>r(?A:7>^^/dide , muft necefliirily move towards that part, from whence it finds leaft refiftance, and fo be accelerated^ as the re- liftance decreafes. Hence the more the water is raifed under that part of its way it is palling above the middle, the fafter it is moved ; And therefore you will find it to move fafter in E then in D, and in D then in C. Neither could I find the floating lubftance to be moved at all, un- til it were placed uponlbme part of the Superficies that was fenlibly ele- vated above the height of the middle part. Now that this may be the true caufe, you may try with a blown Bladder, and an exactly round Ball Upon a very fmooth fide of fome pliable body , as Horn or ^ickyilver^ For if the Ball be placed under a part of the Bladder which is upon one fide of the middle of its preflure , and you prefs ftrongly againft the Bladder,you (hall find the Ball moved from the middle towards the fides.
Having
go Micrographia.
Having therefore fhewn the reafon of the motion of any float towards the (ides, the reafon of the incurfion of any two floating bodies will eafl- ly appear : For the rifing of the water againfl: the iides of either of them,is an Argument fufhcientjto (hew the preflure of the Air to be there lef$5then it is further from it5where it is not lb much elevated 5 and there- fore the reafon of the motion of the other toward it , will be the lame as towards the fide of the Glafs 5 only here from the lame reafon , they are mutually moved toward each other , whereas the fide of the Clals in the former remains fixt. If alfo you gently fill the Jar fo full with water, that the water hprotubera^t above the fides, the fame piece of Cork that before did haften towards the fides , does now fly from it as fall: towards the middle of the Superficies 5 the reafon of which will be found noo-^ ther then this, that the prelTure of the Air is ftronger againfl: the fides of the Superficies G and H, then againfl the middle 1 5 for fince, as I fhewed before, the Principle of congruity would make the terminating Surface Spherical , and that the flatting of the Surface in the middle is from the abatement of the waters preflure outwards, by the contrary indeavour of its gravity 5 it follows that the preflure in the middle muft be lefs then on the fides 5 and therefore the confecution will be the fame as in the former. It is very odd to one that conliders not the reafon of it , to fee two floating bodies of wood to approach earch other,as though they were indued with fome magnetical vigour 5 which brings into my mind what I formerly tried with a piece of Cork or fuch like body, which I fo order- ed, that by putting a little flick into the lame water, one part of the faid Cork would approach and make toward the flick, whereas another would difoede and fly away, nay it would have a kind of verticity , fo as that if the ^Equator ( as I may fo fpeak ) cf the Cork were placed to- wards the flick, if let alone, it would inflantly turn its appropriate Pole toward it, and then run a-tilt at it:and this was done only by taking a dry Cork, and wetting one fide of it with one fmall flroak 5 for by this means gently putting it upon the water, it would deprels the fuperficies on eve- ry fide of it that was dry , and therefore the greatefl preflure of the Air, being near thofe fides caufed it either to chafe away,or elfo to fly oft from any other floating body, whereas that fide only, againfl which the water afeended, was thereby able to attraft.
It remains only, that I fhould determine how high the Water or other Liquor may by this means be railed in a fmaller Pipe above the Superfi- cies of that without it , and at what height it may be foflained : But to determine this, will be exceeding difticult, unlefs I could certainly know how much of the Airs preflure is taken oft by the fmalnels of fuch and foch a Pipe,and whether it may be wholly taken off, that is,whether there can be a hole or pore lb fmall , into which Air could not at all enter, though water might with its whole force ^ for were there fiich , ’tis mani- fefl , that the water might rifo in it to fome five or lix and thirty Englilh Foot high. I know not whether the capillary Pipes in the bodies of fmall Trees, which we call their JUicrojcopical pores ^m^iy not be fuch 3 and whe- ther the congruity of the fides of the Pore may not yet draw the juyee
even
MiCROGRAPHlA.
even higher then the Air was able by its bare prefiure to raife it : For, Congruity is a principle that not only unites and holds a body joyned to it, but, which is more, attracts and draws a body that is very near it, and holds it above its ufual height.
And this is obvious even in a drop of water fufpended under any Si- milar or Congruous body : For,befidcs the ambient prefiure that helps to keep it fiiftein d, there is the Congruity of the bodies that are contigu- ous. This is yet more evident in Tenacious and Glutinous bodies^ fuch as Gummous Liquors, Syrups, Pitch, and Rofin melted^ Tar, Tur- pentine, Balfom, Bird-lime, for there it is evident, that the Parts of the tenacious body, as I may fo call it, do ftick and adhere lb clofe- ly together, that though drawn out into long and very flender Cylin- ders, yet they will not eafily relinquifii one another y and this, though the bodies be aliquatetius fluid, and in motion by one another , which, to (itch as confider a fluid body only as its parts are in aconfuied irregu- lar motion, without taking in alfo the congruity of the parts one among another, and incongruity to fome other bodies, does appear not alittle ftrange. So that befides the incongruity of the ambient fluid to it, we are to confider alfo the congruity of the parts of the contein’d fluid one with another.
And this Congruity (“that I may here a little further explain it ) is both a Tenaceous and an Attradive power ^ for the Congruity, in the Vi- brative motions,may be the caufe of all kind of attradion, not only Ele- drical, but Magnetical alfo, and therefore it may be alfo of Tenacity and Glutinoufnefs. For, from a perfect congruity of the motions of two diffant bodies, the intermediate fluid particles are foparated and dro- ven away from between them, and thereby thofe congruous bodies are, by the incompafling mediums, compelfd and forced neerer together y wherefore that attradtivenefs mufi: needs be ftronger, when, by an im- mediate contact, they are forc’d to be exadly the lame : As I fhew more at large in my ‘Theory of the Magnet. And this hints to me the reafon of the fufpenfion of the Mercury many inches, nay many feet, above the ulu- al ftation of 30 inches. For the parts of §yuick:^lver^ being fo very fimilar and congruous to each other, if once united, will not eafily fuffer a divulfion : And the parts of water, that were any wayes heterogemom^ being by exantlation or rarefaction exhaiifted, the remaining parts being alfo very firailar, will not eafily part neither. And the parts of the Glafr being folid, arc more difficultly disjoyn’d , and the water, being fome- what fimilar to both, is, as it were, a medium to unite both the Glafi and the Mercury together. So that all three being united, and not very difr fimilar, by means of this contad, if care be taken that the Tube in e- reCting be not (hogged, the ^icksilver will remain fufpended, notwidi-^ (landing its contrary indeavour of Gravity, a great height above its or- dinary Station , but if this immediate ContaCt be removed , either by a meer (eparation of them one from another by the force of a (hog, where- by the other becomes imbodied between them , and licks up from the (urface fome agil parts , and fo hurling them makes them air , or elfo
32 M I C R O G R A P H I A.
byfome fmall heterogeneous agil part of the Water, or Air, orQiiick” filver, which appears like a bubble, and by its jumbling to and fro there is '
made way for xht heterogeneous Mther to obtrude, jt ielf between the
Glafs and either of the other Fluids, the Gravity of Mercurj/ precipitates it downward with very great violence 5 and if the Veflel thadiSld^ ^ reftagnating Mercury be convenient, the Mercury will for a time vibrate to and fro with very large reciprocations^ and at laft will remain kept up by the preflure of the external Air at the height of neer thirty inches. And • whereas it may be objefted, that it cannot be, that the meer imbodying of the jEther between thele bodies can be the caufe,fince the JEther ha- ving a free paffage alwayes , both through the Pores of the Glafs, and through thofe of the Fluids , there is no reafon why it fhould not make a leparation at all times whilft it remains fufpended, as when it is violently dif-joynedby a fhog. To this I anfwer. That though the ^ther Tpzffts between the Particles, that is, through the Pores of bodies, fo as that any chafme or feparation being made , it has infinite paflages to admit its en- try into it, yet fuch is the tenacity or attractive virtue of Congruity, that till it be overcome by the meer ftrength of Gravity, or by a fhog afiifting that Conatus of Gravity, or by an agil Particle, that is like a leaver agi^ tated by the Mther 3 and thereby the parts of the congruous fubftances are feparated fb far afunder , that the ftrength of congruity is fo far wea- kened,as not to be able to reunite them, the parts to be taken hold of be- ing removed out of the attraCHve Sphere, as I may fo fpeak, of the con- gruity 3 fuch, I fay, is the tenacity of congruity, that it retains and holds the almoft contiguous Particles of the Fluid , and fuft'ers them not to be feparated, till by meer force that attractive or retentive faculty be over- come : But the feparation being once made beyond the Sphere of the attractive aCtivity of congruity , that virtue becomes of no effeCt at all, but the Mercury freely falls downwards till it meet with a refiftance from the preflure of the ambient Air, able to refift its gravity, and keep it for- ced up in the Pipe to the height of about thirty inches.
Thus have I gently railed a Steel pendulunthj aLoadftone to a great Angle, till by the fbaking of my hand I have chanced to make a fepara- tion between them, which is no fooner made, but as if the Loadftone had retained no attractive virtue, the Tcndulum moves freely from it towards the other fide. So vaft a difference is there between the attractive vir- tue of the when it aCts upon a contiguous and upon a disjoyned
body ; and much more muff: there be between the attraCrive virtues of congruity upon a contiguous and disjoyned body 3 and in truth the attra- ctive virtue is fb little upon a body disjoyned. that though I have with a Microfeope ohf^xvQdiVQxy diligently, whether there were any extraordi- nary on the fide of a drop of water that was exceeding neer
to the end of a green ftick, but did not touch it, I could not perceive the leaft:3 though I found, that as fbon as ever ittoucht it the whole drop would prefently unite it felf with it3 fb thatitfeems an abfolute con- taCl: isrequifite to the exercifing of the tenacious faculty of congruit)\
Obferv.
Micrograp hi a.
Obferv* VII. Of fome^hxnomend. of Glafs drop’s, ;
'^HefeC/^ Drops are fmall [parcels of coarfe green Glals taken out of Jl the Pots that contain the Metal ( as they call it ) in fufioUj upon the end of an Iron Pipe 5 and being exceeding hot, and thereby of a kind of fluggifh fluid Confiftence, are fuffered to drop from thence into a Bucket of cold Water, and in it to lye till they be grown fenfibly cold.
Some of thefe I broke in the open air, by fnapping off a little of the fmall Item with my lingers, others by crufhing it with a finall pair of PJy- ers 5 which I had no fooner done , then the whole bulk of the drop flew violently, with a very brisk noife, into multitudes of fmall pieces, fome of which were as fmall as duff, though in fome there were remaining pieces pretty large, without any flaw at all,and others very much flaw'd, which by rubbing between ones fingers was eafily reduced to duff ^ thefe db fperfed every way fo violently , that fome of them pierced my skin. I could not find,either with my naked Eye,or a Microfcope^ that any of the broken pieces were of a regular figure,nor any one like another , but for the moft part thofe that flaw'd off in large pieces were prettily bran- ched.
The ends of others of thefe drops I nipt off whilft all the bodies, and ends of them lay buried under the water, which, like the former, flew all to pieces with as brisk a noife, and as ffrong a motion.
Others of thefe I tried to break, by grinding away the blunt end^ and though 1 took a feemingly good one , and had ground away neer two thirds of the Ball, yet would it not fly to pieces, but now and then fome fmall rings of it would fiiap and fly off, not without a brisk noife and quick motion,leaving the Surface of the drop whence it flew very pretti- ly branched or creafed , which was eafily difeoverable by the Mierojoope, This drop,after I had thus ground it, without at all impairing the remnant that was not ground away, I caufed to fly immediately all into fand upon the nipping off the very tip of its flender end.
Another of thefe drops I began to grind away at the fmaller end', but had not worn away on theftone above a quarter of an inch before the whole drop flew with a brisk crack into fand or fmall duff 5 nor woul4 it have held fb long , had there not been a little flaw in the piece that I ground away, as I afterwards found.
Several others of thefe drops I covered over with a thin but tery tuff skin of lethyocoUa^ which being very tough and Very tfanfparent,was the mofl: convenient fubftance for thefe tryals that I could imagine, having dipt, I fay, feveral of thefe drops in this tranfparent Glue whilft hot, and fuffering them to hang by a firing tied about the end of them till they werecold, and the skin pretty tough 5 then wrapping all the body of the
G , drop ^
34
Micrographia.
drop C leaving out only the very tip J in fine (upple Kids-leather very clofclyj nipped off the fmall top, and found, as I expeded, that notwith- ftanding this skin of Glue , and the clofe wrapping up in Leather , upon the breaking of the top, the drop gave a crack like the reft, and gave my hand a pretty brisk impuHe; but yet the skin and leather was fo ftrong as to keep the parts from flying out of their former pofture 5 and, the skin being tranfparent , I found that the drop retained exadly its former fi- gure and polifli, but was grown perfedly opacous and all over flaw’d, all thofe flaws lying in the manner of rings, from the bottom or blunt end, to the very top or fmall point. And by feveral examinations with a Micro* fcope^ of feveral thus broken, I found the flaws, both within the body of the drop, and on the outward furface,to lye much in this order.
Let A B in the Figure X of the fourth Scheme reprefent the drop caled over with lUhyocoUa or lji»glafs ( by being ordered as is before pre- ‘ feribed ) crazed or flawed into pieces, but by the skin or cafe kept in its former figure , and each of its flawed parts preferved exadly in its due pofture 5 the outward appearance of it Ibmewhat plainly to the naked eye, but much more confpicuous if viewed with a fmall fenfs appeared imich after this fhape. That is , the blunt end B for a pretty breadth, namely , as far as the Ring C C C feemed irregularly flawed with divers clefts, which all ftemed to tend towards the Center of it, being, as I af- terwards found , and (ball anon ihew in the deftription of the figure Y, the Bafis, as it were, of a Cone, which was terminated a little above the middle of the drop , all the reft of the Surface from C C C to A was flawed with an infinite number of fmall and parallel Rings, which as they were for the moft part very round , fo were they very thick and clofo together, but were not fo exaftly flaw’d as to make a perfect Ring , but each circular part was by irregular cracks flawed like wife into multitudes of irregular flakes or tiles 5 and this order was obforved likewife the whole length of the neck.
Now though I could not fo exadtly cut this conical Body through, the Axis^ as is reprefonted by the figure Y 5 yet by anatomizing^ as it were, offoveral, and taking notice of divers particular circumftances, I was in- formed, that could I have artificially divided a flaw’d drop through the Axis or Center , I fliouldwith a Microfeopeh-Avt^ouud it to appear much of this form , where A fignifies the Apex , and B the blunt end, C C the Cone of the Bafis, which is terminated at T the top or end of it , which feems to be the very middle of the blunt end, in which, not only the co- liical body of the Bafis C C is terminated, but as many of the parts of the drop as reach as high as DD.
And it foemed to be the head or beginning of a Pith, as it v/ere, or a apart of the body which foemed more fpungy then the reft, and much more irregularly flawed, which from T afeended by E E, though lefs vi- fible, into the ihiall neck towards A. The Grain, as it were, of all the flaws, that from all the outward Surface A DC CD A, was much the fame,as is reprefonted by the black ftrokes that meet in the middle D T, DT, DE,DE, &c.
Nor
MlCROGRAPHIAi
Nor is this kind of Grain , as I may call it, peculiar to Glals drops thus quenched 5 for (” not to mention Coperas-jiones ^ and divers other Mar- chajites and Minerals , which I have often taken notice of to be in the very fame manner flaked or grained, with a kind of Pith in the middle I have obferved the lame in all manner of caft Iron , efpecially the coar- ftr Ibrt^ fuchas Steves, and Furnaces, and Backs, and Pots are made of.- For upon the breaking of any of thofe Subftances it is ob\aous to ob- ferve, how from theout-fides towards the middle, there is a kind of Radiation or Grain much relembling this of the Glals-drop^ but this -Grain is moft conlpicuous in Iron-bullets , if they be broken ; the fame ?h<£nomena may be produced by calling regulns of Antimony into a Bullet- mold, as alfo WithGlafs of Antimony^ or with almoft any luch kind of Vitrified Jubfiance , either caft into a cold Mold or poured into Water.
Others of theft Drops I heat red hot in the fire, and then fuflered them to cool by degreeSi And theft I found to have quite loft all tYicirfulmi^ or flying quality, as allb their hard, brittle and Ipringy texture 5 and to emerge of a much fofter temper, and much eafier to be broken or Inapt with ones finger^but its ftrong and brittle quality was quite deftroy- cd, and it ftemed much of the fame confiftence with other green Glaft well nealed in the Oven.
The Figure and bignels of theft for the moft part was the lame with that of the Figure Z ^ that is,all the furface of them was very finooth and polilht,and for the moft part round , but very rugged or.knobbed about D, and all the length of the ftem was here and there pitted or flattedi. About D, which is at the upper part of the drop under that fide of the ftem which is concave , there ufually was made fomeoneor more little Hillocks or Prominences. The drop it ftlf, before it be broken, appears very tranlparent, and towards the middle of it, to be very full of fmall Bubbles, of Ibme kind of aerial fubftance, which by the refraction of the outward lurface appear much bigger then really they are, and this may be in good part removed, by putting the drop under the lurface of clear Water, for by that means moft part of the refraCtion of the convex Sur- face of the drop is deftroyed , and the bubbles will appear much finaller* And this, by the by, minds me of the appearing magnitude of t\\G aper- ture o£ tixtiris^ox pupil oixh^ eye, which though it appear, and be there- fore judged very large , is yet not above a quarter of the bignels it ap- pears of^ by the lenticular refraCHon of the Cornea.
The cauft of all which Vh<£nomena I imagine to be no other then this. That the Parts of the Glals being by the exceflive heat of the fire kept off and ftparated one from another, and thereby put into a kind of Hug- gift] fluid confiftence , are ftflered to drop oft with that heat or agitation remaining in them, into cold Water 5 by which means the outfides of the drop arc prefently cool’d and crufied , and are thereby made of a looft texture,becauft the parts of it have not time to fettle themftlves leifurely together , and lb to lie very cloft together : And the innermoft parts of the drop, retaining ftill much of their former heat and agitations, remain
G 2 of
Micrographia.
of a loofe texture alfojand^^according as the cold ftrikes inwards from the bottom and (ides, are quenched, as it were, and made rigid in that very pofture wherein the cold finds them. For the parts of thecruji being already hardened , will not fuffer the parts to fhrink any more from the outward Surface inward 5 and though it fhrink a little by reafon of the fmall parcels of feme Aerial fubftances difperfed through the matter of the Glafs, yet that is not neer fo much as it appears f as I juft now hint- ed O nor if it were, would it be fufheient for to confblidate and condenfe the body of Glafs into a tuff and dole texture , after it had been lb ex^ ceflively ratified by the heat of the glals-Furnace.
But that there may be Inch an expanfion of the aerial fubftance con- tained in thofc little blebbs or bubbles in the body of the drop, this fob lowing Experiment will make more evident.
Take a fmall Glals-Canc about a foot long , feal up one end of it «fet/V^/^,then put in a very fmall bubble of Glals, almoftof theftiape of an Eflence-viol with the open mouth towards the lealed end , then draw out the other end of the Pipe very fmall, and fill the whole Cylinder with water , then fet this Tube by the Fire till the Water begin to boyl , and the Air in the bubble be in good part ratified and driven out , then by fucking at the fmalling Pipe, more of the Air or vapours in the bubble may be luck’d out , lb that it may fink to the bottom 5 when it is funk to the bottom,in the flame of a Candle,or Lamp,nip up the flender Pipe and let it cool : whereupon it is obvious to oblerve, firft, that the Water by degrees will llibfide and fhrink into much lels room : Next, that the Air or vapours in the Glals will expand themfelves lb, as to buoy up the little Glals : Thirdly, that all about the infide of the Glals-pipe there will ap- pear an infinite number of fmall bubbles, which as the Water grows colder and colder will fwell bigger and bigger, and many of them buoy them- lelves up and break at the top.
From thisDifiediug of the heat in Glals drops, that is, by the quenching or cooling Irradiations propagated from the Surface upwards and in- wards, by the lines CT, CT, DT, DE,C^c. the bubbles in the drop have room to expand themfelves a little, and the parts of the Glals con- tradt themfelves 5 but this operation being too quick for the lluggilh parts of the Glafs, the contraftion is performed very unequally and irregularly, and thereby the Particles of the Glals are bent, Ibme one way, and Ibme another, yet lb as that moft of them draw towards the Pith or middle TEEE, or rather from that outward : fo that they cannot extricate on unbend themfelves, till fome part of T E E E be broken and loofened, for all the parts about that are placed in the nianner of an Arch , and lb till their hold at T EE E be loofened they cannot fly afunder, but up- hold, and Ihelter, and fix each other much like the ftones in a Vault, where each ftone does concurre to the ftability of the whole Fabrick, and no one ftone can be taken away but the whole Arch falls. And where- Ibever any of thofe radiating wedges DT D,€^c. are removed, which are the component parts of this Arch,the whole Fabrick prefently falls to
pieces t
M 1 C ROG R A P HlA.
pieces^ for all the Springs of the feveral parts are fet at liberty, ^which immediately extricate themfelves and tly afunder every way ^ each part by its fpring contributing to the darting of it lelf and fome other contigu- ous part. But if this drop be heat lb hot as that the parts by degi'ces cart unbend themfelves, and be fettled and annealed in that pofture , and be then luffered gently to iubfide and cool ^ The parts by this nealing lo- fing their fpringinels , conftitute a drop of a more foft but iefs br ittle tex- ture,and the parts being not at all under a flexure, though any part of the middle or Pith T E E E be broken,ye$jWill not the drop at all fly to pieces as beforCi ’ .
This Conjedure of mine I fliall indeavour to make out by explain- ing each particular Allertion with analogous Experiments ; The Aflertion« are thcfe.
Firft , That the parts of the Clafs , whilfl: in a fluid Confiftence and hot , are more ratified , or take up more room , then when hard and cold.
Secondly 5 That the parts of the drop do fufler a twofold contra- dion.
Thirdly , That the dropping or quenching the glowing metal in the Water makes it of a hard*, fpringing, and rarified texture^
Fourthly , That there is a flexion or force remaining upon the parts of the Glafs thus quenched , from which they indeavour to extricate themfelves.
Fifthlyj That the Fabrick of the drop, that is able to hinder the parts from extricating themfelves, is anahgus to that of an Arch.
Sixthly, That the hidden flying aliinder of the parts proceeds fioirt their fpringinels.
Seventhly, That a gradual heating and cooling does anneal or reduce the parts of Glafs to a texture that is more loofe, andealilicr to be bro- ken, but not lb brittle.
That the firft of thefe is true may be gathered from this, That Heat is a property of a body arftng from the motion or agitation of its parts 5 and therefore whatever body is thereby toucht muft neceflarily receive Ibmc part of that motion,whereby its parts will be lhaken and agitated, and lb by degrees free and extricate themfelves from, one another , and each part fo moved does by that tnotion exert a conatns of protruding and diP placing all the adjacent Particles,! Thus Air included in a veliel, by be- ing heated will burft it to pieces. Thus have I broke a Bladder held over the fire in my hand, with fuch a violence and noile , thatitalmoft made me deaf for the prefent,and much lurpalled the noife of a Musket; The like have I done by throwinginto the fire fmall glals Bubbles her- metically lealed , With a little drop of Water included in them. Thus Water alfo,orany other Liquor ,included in a convenient veftel,b}" being wanned , manifeftly expands it felf with a very great violence , lb as to break the ftrongeft vefid, if when heated it be narrowly itnprilbned in it.
This
MlCROGRAPHiA.
This is very manifeft by the feakdThermometers^ which I have, by feve^ ral tryals, at laft brought to a great certainty and tenderneis : for I have made fome with ftems above four foot long , in which the expanding Li- quor would fo far vary,as to be very neer the very top in the heat of Sum- mer, and prety neer the bottom at the coldeft time of the Winter. The Stems I ufo for them are very thick,ftraight,and even Pipes of Glals,with a very fmall perforation , and both the head and body I have made on purpole at the Glafs-houfe , of the lame metal whereof the Pipes are drawn ; thele I can eafily in the flame of a Lamp, urged with the blafl: of a pair of Bellows, feal and clofe together, fo as to remain very firm, clofe and even 5 by this means I joyn on the body firftjand then fill both it and a part of the ftem, proportionate to the length of the ftem and the warmth of the lealbn I fill it in^with the befi: rectified Spirit of Wine high* ly ting cl with the lovely colour of Cocheneel^ which I deepen the more by pouring Ibme drops of common Spirit of Vrine , which mull: not be too well redified , becaufe it will be apt to make the Liquor to curdle and fl:ick in the Imall perforation of the liem. This Liquor I have upon tryal found the mofi: tender of any fpirituous Liquor,and thole are much more fenfibly affeded with the variations of heat and cold then other more fiegmatick and ponderous Liquors, and as capable of receiving a deep tindure, and keeping it,as any Liquor whatfoeVer 5 and ( which makes it yet more acceptable ) is not fubjed to be frozen by any cold yet known. When I have thus filled it, I can very eafily in the foremention- ed flame of a Lamp feal and joyn on the head of it.
Then, for graduating the Item, I fix that for the beginning of my di- vifion where the furface of the liquor in the ftem remains when the ball is placed in common diftilled water, that is fo cold that it juft begins to freeze and fhoot into flakes 5 and that mark I fix at a convenient place of the ftem, to make it capable of exhibiting very many degrees of cold, below that which is requifite to freeze water : the reft of my divifions, both above and below this (which I mark with a [o(] or nought^ I place according to the Degrees of Expandon^ or ContratUon of the Liquor in proportion to the bulk it had when it indur’d the newly mention’d freez- ing cold. And this may be very eafily and accurately enough done by this following way ^ Prepare a Cylindrical veflel of very thin plate Brals or Silver, A B C D of the figure Z 5 the Diameter A B of whole cavity let be about two inches, and the depth B C the lame ^ let each end be cover’d with a flat and fmooth plate of the lame fubftance, clolely Ibder’d on, and in the midft of the upper cover make a pretty large hole E F, about the bignefs of a fifth part of the Diameter of the other 5 into this faften very well with cement a ftraight and even Cylindrical pipe of Glals, E F G H, the Diameter of whofe cavity let be exactly one tenth of the Diameter of the greater Cylinder. Let this pipe be mark’d at G H with a Diamant, lb that G from E may be diftant juft two inches, or the lame height with that of the cavity of the greater Cylinder, then divide the length EG exactly into 10 parts, fo the capacity of the hollow of each of thele divifions will be part of the capacity of the greater Cylin^
MiCROGRAPHlA.
der. This veffel being thus prepared, the way of marking and gradu- ating the ‘ihermometers may be very eafily thus performed :
Fill this Cylindrical veflel with the fame liquor wherewith the momeUrs are fill’d, then place both it and the ihermometer you are td gmdtute^ in water that is ready to be frozen, and bring the furface of the liquor in the Jhermometer to the firft marke or [o], then fo proportion the liquor in the Cylindrical veliel, that the furface of it may )uft be at the lower end of the fmall glafs-Cylinder ^ then very gently and gradu- ally warm the water in which both the and this Cylindrical
veflel ftand, and as you perceive the ting’d liquor to rife in both ftems^ with the point of a Diamond give feveral marks on the ftem of the Ther- mometer at thofe places, which by comparing the expanfion in both Stems, are found to correfpondto the divifions of the cylindrical veflel;> and having by this means marked Ibme few of thefe divifions on the Stem 3 it will be very eafie by thefe to mark all the reft of the Stem, and accordingly to aflign to every divifion a propet charadter.
A ihermometer , thus marked and prepared, will be the fitteft Inftru- ment to make a Standard of heat and cold that cah be imagined. For being fealed up, it is not at all lubjeft to variation or wafting, nor is it lia- ble to be changed by the Varying prefliire of the Air , which all other kind of Thermometers that are open to the Air are liable to. But to pro- ceed.
This property of Expanfion with Heat, and Contraftion with Cold, is not peculiar to Liquors only, but to all kind of (olid Bodies alfo, elpeci- ally Metals, which will more manifeftly appear by this Experiment.
Take the Barrel of a Stopcock of Brafs, and let the Key, which is well fitted to it, be riveted into it,fo that it may llip,and be eafily turned round, then heat this Cock in the fire, and you will find the Key fo fwollen, that you will not be able to turn it round in the Barrel 5 but if it be fufiered to cool again, as loon as it is cold it will be as movable, and as eafie to be turned as before.
This Quality is alfo very obforvable in Lead^ Tih^ Silver.^ Antimony^ Titch^RofinyBees-tpaxyButterymdi the like^ all which, if after they be melted you lufler gently to cool , you lhall find the parts of the upper Surface to liibfide and fall inwards , lofing that plumpnefs and fmoothnels it had whilftin fufion. The like I have alfo obferved in the cooling of Clajs of Antimony^ which does very neer approach the nature of Glals,
But becaule thefe are all Examples taken from other materials then Glals,and atgue only, that poflibly there may be the like property alfo in Glals, not that really there is 5 we lhall by three or four Experiments in- deavour to manifeft that alfo.
And the Firft is an Oblervation that is very obvious even in thefe very drops, to wit,that they are all of them terminated with an unequal or ir- regular Surface , elpecially about the fmaller part of the drop , and the whole length of the ftem 5 as about D, and from thence to A, the whole Surface , which would haVe been round if the drop had cool’d leilurely, is, by being quenched haftily,very irregularly flatted and pitted 5 which
Micrograph! A.
I fuppofe proceeds partly from the Waters unequally cooling and pref* fing the parts of the drop, and partly from the felt-contradcing or fubfi- ding quality of the fubftance of the Glafs: For the vehemency of the heat of the drop caufes luch hidden motions and bubbles in the cold Wa- ter,that fome parts of the Water bear more forcibly againft one part then againft another , and confequently do more fuddenly cool thofe parts to which they are contiguous.
A Second Argument may be drawn from the Experiment of cutting Glafles with a hot Iron. For in that Experiment the top of the Iron heats, and thereby rarifies the parts of the Glafs that lie jull: before the crack , whence each of thole agitated parts indeavouring to expand its lelf and get elbow-room, thrufts off all the reft of the contiguous parts, and conlequently promotes the crack that was before begun.
A Third Argument may be drawn from the way of producing a crack in a found piece or plate of Glals, which is done two wayes, either Firft, by fuddenly heating a piece of Glals in one place more then in another. And by this means Chymijis ufually cut off the necks of Glals-bodies, by two kinds of Inftruments, either by a glowing hot round Iron-Ring, which juft incompafles the place that is to be cut, orelfo by a Sulphur'd Threed, which is often wound about the place where the feparation is to be made, and then fired. Or Secondly^A Glafs may be cracked by cooling it fuddenly in any place with Water, or the like, after it has been all lei- forely and gradually heated very hot. Both which Th£fiomena leem ma- nifeftly to proceed from the expanjion and contraftion of the parts of the Glafs , which is alfo made more probable by this circumftance which I have obferved , that a piece of common windbw-glafs being heated in the middle very luddenly with a live Coal or hot Iron,does ufoally at the firft crack fall into pieces, whereas if the Plate has been gradually heated very hot , and a drop of cold Water and the like be put on the mid- dle of it, it only flaws it, but does not break it afunder immedi- ately.
A Fourth Argument may be drawn from this Experiment 5 Take a Glals-pipe, and fit into it a folid ftick of Glals, fo as it will but juft be mo- ved in it. Then by degrees heat them whilft they are one within ano- ther,and they will grow ftiffer, but when they are again cold, they will be as eafie to be turned as before. This Expanfion of Glafs is more mani- feft in this Experiment.
Take a ftick of Glals of a confiderable length, and fit it fo between the two ends or forews of a Lath, that it may but juft eafily turn,and that the very ends of it may be juft toucht and lufteined thereby ; then applying the flame of the Gandle to the middle of it, and heating it hot, you will prefontly find the Glals to ftick very faft on thofo points, and not without much difficulty to be convertible on them , before that by removing the flame for a while from it, it be fuffered to cool, anden y ou will find it as eafie to be turned round as at the firft.
From all which Experiments it is very evident , that all thofe Bodies, and particularly Glafs, fuflers an Expanfion by Heat, and that a very con- fiderable
Ml CROGRAPHIA.
fidferable 6ne,whilft they are in a ftate of Fufion. For I elfewhere
mentionj hafignothinghut an eff'eU of a Very fir ong and qnh-k^.JiMiqng whereby the farts arenas it rverejoofe'mdfmm. eaeh oiher^aml confynentiy^ leaTJt an interjacent face or vacuity 3 it folloivSi that all thole fhaken Particle muft heceflarily take up much more rooiii then when they were atxeftjand iay tjuietiy upon each other; And this is further confirmed by ^Patic£ hc^Ii^ Alabfiief which will hlanifeftly rife a fi?tlh or eighth part highef in ihe Po^ whiidit is boylingj then it will remain at^ both before and aftbrit be boyjv ed.The reafon of which odd Vbandmeiiin ' ( to hint inhere only the way!)
is this f that there is in the dirious pdWtier of Alabaher^andicthdr'aakiding Stories, a certain watery fubfiance^ Whii:^hhfo'fi^^nd inbldded \V-ith tht folid Particles, that till the heat be very Gonfiderable they will not% away'5 blit after the heat is increafed tO fuch a degree , they Weak out every Way- in vapours, and thereby lb fhake and loOfen the Ihiall eorpiifies of the Pow- der from each other, that they become perfectly of the ridture-gf a fluid bo^ dy, arid one may move a Itick to arid fro through itj and ftir it as bafily as Water, and the Vapours burfl: and break out in bubbles juft as in bbyling Watei,and the like 3 whereas^ both before thofe watery parts are flying away, and after they are quite gone 5 thatls, beforehand dfter it have doriO boyling,all thofe eflefts ceafe , and a ftick is ds diffieultly moved to arid fro in it as in land, or the like. Which Explication I could eafily prove^ had ! time 5 but this is not a fit place for it. ’
To proceed therefore,! fay,thatthe droppirig of this expahded Body in- to cold Water, does make the parts of the Gklfs fufler a double conttabriori : The firft is, of thole parts which are rieer the Surface of thC Dfbpi FOr Cold, aslfaid befOre,contra£cingBodics,friatisi^y the abatetneyH 'of the^agifating fd-- (culty the parts fallingneerer together thepdrts next ddjoyirig to the Wateir riiuft needs lofe much of their motion ^ drid impart it to the AmbieriC-Watet (which the Ebullition and commotion of it manifcfts) and thereby betOriie a Iblid and hard cruft, Whilft the inrietmoft parts remain yet fiitidiand Ex- panded 5 whence, as they grow cold alfoby degreeS,their parts ffliift ttecefla:- rily be left at liberty to be cOndenled, but becdUleof the hardnefe of the outward eruft,the contrayiiori cannot be admitted thdt way^but there being many very Imall, and before iricOillJlicliOtW bubbles in the fubftarice of the Glals,Upon the lubliding of the parts of the Glafs,the agil lubftarice contain^ ed in them has liberty of exparidihg if lelf a litflejdrid thereby thofe bubblel grow much bigger jwhich is the leeorid Coritf actibh. Arid both thefe are fcori^ firmed from the appearance of the Drop it felf : for as for the OutWard parts^ wc fce,firft,that it is irregular and flifririik, as it were,- which is Catifed by the yielding a little of the hardened Skin to a Corittafciori , after the vEry olit- moft Surface is fettled 5 arid asfof theiritEfnal parts, one may With oiies naked Eye perceive abundance Of vety cohlpiCiiOtfs bubbles, and with the ^ierofcope mmy moxQi
The Conlideration of which Particulars will eafily fhake the Third Politic on probablcjthat is,that the parts of the dfOp Will be Of a very hard, though of a ratified Texture 5 for if the outward parts of the Drop, by reafori of its hard cruft, will indure very little Gontr adion, and the igil Particles,^ iticlti-
H ded
Micrographia.
ded inthofe bubbles, by the lofing of their agitation, by thedecreafe of the Heat,lo(e alfo moft part of their Spring and Expanfive power^it follows (the withdrawing of the heat being very ludden) that the parts muft be left in a very loofe Texture, and by reaibn of the implication of the parts one about another,which from their lluggifrines and glutinoufnelslluppole to be much after the manner of the flicks in a Thorn-bufh,or a Lock of Woofrit will fol- low, I lay, that the parts will hold each other very ftrongly together,and in- dcavour to draw each other neerer together , and confcqucntJy their Tex- ture muft be very hard and ftifl, but very much ratified.
And this will make probable my next Pofition, That the parts of the Glafi ure under a kind of tenjion or flexure^out of which they indeavour to extricate and free thetnje Ives ^znd thereby all the parts draw towards the Center or middle, and would, if the outward parts would give way, as they do when the out- ward parts cool leilurely (as in baking of ClaflesJ) contrad the bulk of the drop into a much Ids compafs. For fince.as I proved before,the Internal parts of the drop, when fluid, were of a very ratified 1 exture,and,as it were,tos’d open like a Lock of Wool, and if they were fuffered leifurely to cool, would be again preft, as it were, dole together; And lince that the heat, which kept them bended and open, is removed , and yet the parts not fufiered to get as neer together as they naturally would , It follows,that the Particles remain under a kind of tenfon and flexure , and conlequently have an indeavour to free themlelves from that bending and diflenjion^ which they do, as loon as either the tip be broken, or as foon as by a leifurely heating and cooling, the parts are nealed into another pofture.
And this will make my next Pofition probable,that the parts of theGlafs drops are contignated together in the form of an Archymd cannot any where yield or be drawn inwards,till by the removing of Ibme one part of itfas it happens in the removing one of the ftones of an Arch)the whole Fabrick is (hatter d,ahd falls to picces,and each of the Springs is left at liberty ,fuddenly to extricate it felf: for fince I have made it probable,that the internal parts of the Glafs have a contradive power inwards, and the external parts are incapable of (uch a Contradion,and the figure of it being (pherical^it follows,that the fuperficial parts muft bear againft each other , and keep one another from being con- dens’d into a le(s room, in the (ame manner as the ftones of an Arch conduce to the upholding each other in that Figure. And this is made more probable by another Experiment which was communicated to me by an excellent Per- Ibn,who(e extraordinary Abilities in all kind of Knowledg, efpecially in that of Natural things,and his generous Dilpofition in communicating,incouraged me to have recourlc to him on many occafions. The Experiment was this ; Small Glals-balls ( about the bignefs of that reprelented in the Figure &.) would, upon rubbing or fcratching the inward Surface, fly all infiinder, with a pretty brisk noi(e 5 whereas neither before nor after the inner Surface had been thus (cratcht, did there appear any flaw or crack. And putting the pie- ces of oneofthofe broken ones together again, the flaws appeared much after the manner of the black lines on the Figure, Thele Balls were fmall,
but exceeding thick bubbles of Glals , which being crack’d off from the Tuntilion whilft very hot , andfo fuffered to cool without nealing them in
the
Micrograph! A.
the Oven over the Furnace , do thereby (f being made of white diafs, \v hich cools much quicker then green Clafs , and is thereby made much brittlerj acquire a very porous and very brittle texture: lb that if with the point of a Needle or Bodkin , the infide of any of them be rubbed prety hard, and then laid on a Table , it will, within a very little while, break into many pieces with a brisk noife , and throw the parts above a Ijpan afunder on the Table: Now though the pieces are not (b fmallas thofe of a fulminating drop, yet they as plainly Ihew, that the outward parts of the Glals have a great Conatus to fly afunder, were they not held together by the tenacity of the parts of the inward Surface : for we fee as fbon as thofe parts are crazed by hard rubbing, and thereby their tena- city fpoiled, the fpringinels of the more outward parts quickly makes a divulfion, and the broken pieces will, if the concave Surface of them be further fcratcht with a Diamond, fly again into fmaller pieces.
From which preceding confiderations it will follow Sixthly , That the flidden flying afunder of the parts as fbon as this Arch is any where difbr- dcred or broken, proceeds from the fpringing of the parts , which ,indea- vouring to extricate themfelves as fbon as they get the liberty , they per- form it with fuch a quicknefs,that they throw one another away with very great violence .* for the Particles that compofe the Cruft have a Cohatus to lye further from one another,and therefore as foon as the external parts are locfened they dart themfelves outward with great violence, juft as fb many Springs would do, if they were detained and faftened to the body, as foon as they fhould be fuddcnly loofenedj and the internal parts draw- ing inward, they contraft fo violently, that they rebound back again and fly into multitude of fmall fhivers or fands. Now though they appear not, either to the naked Eye, or the Microfeope^ yet I am very apt to think there may be abundance of fmall flaws or cracks , which , by reafbn the ftrong refleding Air is not got between the contiguous parts, appear not* And that this may be fo , I argue from this , that I have very often been able to make a crack or flaw, in fbme convenient pieces of Glafs,to appear anddilappear atpleafure, according as by preffing together, or pulling aliinder the contiguous parts , I excluded or admitted the ftrong refled- ing Air between the parts : And it is very probable, that there may be ferae Body, that is either very ratified Air, or (ornerKinganalogoustoit, which fills the bubbles of thefe drops , which I argue, firft, from the round- nefs of them, and next, from the vivid refledtion of Light which they ex- hibite ; Now though I doubt not , but that the Air in them is very much rarified,yet that there is feme in them, to fuch as well eonfidcr this Expe- riment of the difappearing of a crack upon the extruding of the Air j I fuppofe it will feem more then probable.
I’he Seventh and laft therefore that I fhall prove, is. That the gradual heating and cooling of thefe fo extended bodies does reduce the parts of the clafs to a loojer and fof ter temper. And this I found by heating them, and keeping them lor a prety while very red hot in a fire , for thereby I found them to grow a little lighter , and the fmall Stems to be very eafily bro- ken and Inapt any where , without at all making the drop fly j whereas
H 2 before
Micrographia.
before they were fo exceeding hardjthat they could not be broken with» out much difficulty , and upon their breaking the whole drop would fly in pieces with very great violence. The Reafon of which laft leems to be 5 that the leifurely heating and cooling of the parts does not only waft fome part of the Glalsit felf , but ranges all the parts into abetter order, and gives each Particle an opportunity of relaxing its felf, and confequently neither will the parts hold fo ftrongly together as before, nor be fo difficult to be broken : The parts now more eafily yielding, nor will the other parts fly in pieces , becaufe the parts have no bended Springs. The relaxation alfo in the temper of hardned Steel , and ham- mered Metals.by nealing them in the fire,leems to proceed from much the fame caufe. F or both by quenching fuddenly fuch Metals as have vitri~ fed parts interfpers’d, as Steel has,and by hammering of other kinds that do not fo much abound with them, as Silver, Brafs, &c. the parts are put into and detained in a bended pofture , which by the agitation of Heat are ftiaken, and loofened, and (uffered to unbend themfclves.
Obferv. VIII. Of the fiery Sparks ftruck from a Flint or Steel,
]T is a very common Experiment , by ftriking with a Flint againft a Steeljto make certain fiery and fhining Sparks to fly out from between thofe two comprefling Bodies. About eight years fince , upon cafoally reading the Explication of this odd Phenomenons by the moft Ingenious Des Cartes , I had a great defire to be latisfied , what that Subftance was that gave fuch a fhining and bright Light ; And to that end I fpread a fheet of white Paper,and on it, obferving the place where feveral of thefe Sparks fcemed to vanifh, I found certain very (mall, black, but gliftering Spots of a movable Subftance, each of which examining with my Mifero- cope^l found to be a fmall round Globule 5 fome of which, as they looked prety fmall, fo did they from their Surface yield a very bright and ftrong reflexion on that fide which was next the Light 5 and each look’d almoft like a prety bright Iron-Ball, whofe Surface was prety regular, fuch as is reprefented by the Figure A. In this I could perceive the Image of the Window prety well, or of a Stick, which I moved up and down between the Light and it. . Others I found,which were, as to the bulk of the Ball, prety regularly round, but the Surface of them,as it was not very foiooth, but rough,and more irregular, fo was the refleftion from it more faint and confufed. Such were the Surfaces of B. C. D. and E. Some of thefe I found cleft or cracked, asC, others quite broken in two and hollow, as D. which fcemed to be half the hollow fhell of a Granado, broken irre- gularly in pieces. Several others I found of other fhapes 3 but that which is reprefented by E, I obferved to be a very big Spark of Fire, which went out upon one fide of the Flint that I ftruck fire withal! , to
which
Micrographia.
which it ftuckby the root F, at the end of which fmall Stem wasfeften- ed-on aHemJphere^ or half a hollow BalljWith the mouth of it open from the ftemwardsj fo that it looked much like a Funnel, or an old £a(hioned Bowl without a foot. This night, making many tryals and obfervations of this Experiment,! met, among a multitude of the Globular ones v/hich I had obferved, a couple of Inftances, which are very remarkable to the confirmation of my Hypothefis.
And the Firft was of a pretty big Ball faftened on to the end of a linall (liver of Iron,which Compofitum feemed to be nothing elfe but a long thin chip of Iron, one of whofe ends was melted into a fmall round Glob^^the other end remaining unmelted and irregular, and perfectly Iron.
The Second Inftance was not lefs remarkable then the Firft 5 for I found, when a Spark went out, nothing but a very fmall thin long fliver of Iron or Steel , unmelted at either end. So that it feems, that fome of thefe Sparks are the (livers or chips of the Iron vitrified , Others are on- ly the flivers melted into Balls without vitrification , And the third kind are only fmall flivers of the Iron, made red-hot with the violence of the ftroke given on the Steel by the Flint.
He that (hall diligently examine the Phenomena of this Experiment, will, I doubt not, find caufe to belieVe, that the realbn I have heretofore given of it, is the true and genuine caufe of it, namely. That the Sparky appearing Jo bright in the fallingys nothing elfe but a jmali piece of the Steel or Flint-^ but mofi commonly of the Steely which by the violence of the firok§ if at the fame time fever d and heatt red-hot , and that fometimes to fitch d degree ^ as to makg it melt together into a fmall Globule of Steel 5 and fome- times alfo is that heat fo very intenfe^ as further to melt it and vitrifie it 5 but many times the heat is fo gentle^ as to be able to make the fliver only redhoty which notwithfianding falling upon the tinder ( that is only a very curious (mail Coal made of the fmall threads of Linnen burnt to coals and chafdj it eafily fits it on fire. Nor will any part of this Hypothefis feem ftrange to him that confiders, Firft, that either hammering, or filing, or otherwife violently rubbing of Steel, will prefently make it fo hot as to be able to burn ones fingers. Next , that the whole force of the ftroke is exerted upon that (mail part where the Flint and Steel firft touch : For the Bodies being each of them fo very hard , the puls cannot be far com- municated, that is, the parts of each can yield but very little, and there- fore the violence of the concuflion will be exerted on that piece of Steel which is cut off by the Flint. Thirdly , that the filings or fmall parts of Steel are very apt, as it were,to take fire, and are prefently red hot, that isjthere feems to be a very combufiible fulphnreous Body in Iron or Steel, which the Air Very readily preys upon, as foon as the body is a little vio- lently heated.
And this is obvious in the filings of Steel or Iron caft through the flame of a Candle 3 for even by that fudden of the fmall chips of Iron,
they are heat red hot, and that combufiible Julphureous Body is prefent- ly prey’d upon and devoured by the incompafling Meifiruum,
whofe office in this Particular I have (hewn in the Explication of Char- cole. And
4^ M I C R O G R A P H I A .
And in profecution of this Experiment^having taken the filings of Iron and Steel, and with the point of a Knife call: them through the flame of a Candle , I obferved where Ibrae confpicuous Ihining Particles fell , and looking on them with my Microfiope , I found them to be nothing elfe but fuch round Globules, as I formerly found the Sparks ftruck from the Steel bv a ftroke to be, only a little bigger ^ and (baking together all the filings that had fallen upon the (heet of Paper underneath, and obferving them with the Mkrofcope. I found a great number of (mall Globules, (uch as the former, though there were alio many of the parts that had remain- ed untoucht, and rough filings or chips of Iron. So that, it Teems, Iron does contain a very combufiible fidphnreous Body, which is, in all likeli- hood, one of the caufes of this Vh^nomenon , and which may be perhaps very much concerned in the bufinels of its hardening and tempering ; of which fomewhat is Tiid in the Delcription of Mujiovy-gUfs.
So that, thefe things confidered, we need not trouble our (elves to find out what kind of Pores they are, both in the Flint and Steel, that contain the Atoms of fire , nor how thofe Atoms come to be hindred from run- ning all out , when a dore or paflage in their Pores is made by the con- cuflion ; nor need we trouble our felves to examine by what Vrometheus the Element of Fire comes to be fetcht down from above the Regions of the Air, in what Cells or Boxes it is kept, and what Epimethens lets it go : Nor toconfider what it is that caufes (b great a conflux of the atomical Particles of Fire, which are faid to fly to a flaming Body, like Vultures or Eagles to a putrifying Carcals, and thereto make a very great pudder. Since we have nothing more difficult in this Hypothejis to conceive, fir(t, as to the kindling of Tinder, then how a large Iron-bullet, let fall red or glowing hot upon a heap of Small-coal, (houldfet fire to thole that are next to it firfl: ; Nor fecondly, is this lafi: more difficult to be explicated, then that a Body, as Silver for Inftance, put into a weak Menjiruum^ as Aqua fortis (hould , when it is put in a great heat , be there diflblved by it, and not before 5 which Hypothefis is more largely explica- ted in the Delcription of Charcoal. To conclude, we (ee by this In- ftance, how much Experiments may conduce to the regulating of Philo- fophical notions. For if the moft Acute Des Carteshzd applied himfelf experimentally to have examined what fubftance it was that caufed that Ihining of the falling Sparks ftruck from a Flint and a Steel , he would certainly have a little altered his , and we (hould have found,
that his Ingenious Principles would have admitted a very plaufible Ex- plicadon of this Phenomenon , whereas by not examining (b far as he might , he has fet down an Explication which Experiment do’s contra- did.
But before I leave this Defcription, I muft not forget to take notice of the Globular form into which each of thele is moll curioudy formed. And ^s Phenomenon^ as I have ellewhere more largely (hewn, proceeds from a' propriety which belongs to all kinds of fluid Bodies more or le(s,and is caufed by the Incongruity of the Ambient and included Fluid, which lb afts and modulates each other , that they acquire , as neer as is
poflible.
Micrograph! A.
pofliblc^ja fperical ov globular iovm^ which proprifety and (everal of the ?h£itomena that proceed from it, 1 have more fully explicated in the fixth Oblervation.
One Experiment, which does very much illuftrate my pre/ent Explica- tion, and is in it felf exceeding pretty, I muft not pafs by : And that is a way of making fmall ov Balls of Lead, or Tin, as finall alraoft as
thefe of IrOn or Steel, and that exceeding eafily and quickly, by turning the filings or chips of thole Metals allb into perfectly round Globules^ The wayj in lhort,as I received it from the Learned Thyjitian Do&or I. G. is this 5
Reduce the Metal yOu would thuslhape, into exceeding fine filings, the finer the filings are, the finer will the Balls be: Stratifie^e.(c filings with the fine and well dryed powder of quick Lime in a Crucible propor- tioned to the quantity you intend to make ; When you have thus filled your Crucible^ by continual firatifications of the filings and powder, fb that.as neerasmay be, no one of the filings may touch another, place the Crucible in a gradual jire , and by degrees let it be brought to a heat big enough to make all the filings, that are mixt with the quick Lime, to melt, and no more 3 for if the fire be too hot , many of thefe filings will joyn and run together 3 whereas if the heat be proportioned j upon walhing the Lime-duft in fair Water , all thofe fmall filings of the Metal will lub- fide to the bottom in a moft curious powder , confiding all of exactly round Globules^ which, if it be very fine, is very excellent to make Hour- glaflb of.
Now though quick Lime be the powder that this direftion makes choice of, yet I doubt not, but that there may be much more convenient ones found out, one of which I have made tryal of, and found very effe- ftual 3 and were it not for difeovering, by the mentioning of it, another Secret ^ which I am not free to impart , I Ihould have here inferred it.
Obferv. IX. Of the Colours obfervahle in Mufeovy Glafs^ and other thin Bodies.
M01covy“glals,or La^is Jpecularif^jis a Body that (eems to have as ma- ny Guriofities in its Fabrick as any common Mineral I have met with : for firft , It is tranfparent to a great thicknefs : Next, it is com- pounded of an infinite number of thin flakes joyned or generated one upon another fo elofe & fmooth,as with many hundreds of them to make one Imooth and thin Plate of a tranlparent flexible fiibftance,which with care and diligence may be flit into pieces fo exceedingly thin as to be hardly perceivable by the eye, and yet even thofo, which I have thought the thinned, I have with a good Microjeope found to be made up of many ether Plates, yet thinner 3 and it is probable, that. Were our
much
Ml CROGRAP HIA.
much better , we might mueh further difcover its divifibility. Nor are thefc flakes only regular as to the fmoothnels of their Surfaces , but third- ly 5 In many Plates they may be perceived to be terminated naturally with edges of the figure of a Rhomhodd. This Figure is much more con- Ipkuous in our Englifli talk, much whereof is found in the Lead Mine's, and is commonly called spar , and Kauck^ ^ which is of the lame kind of liibftance with but is feldom found in fo large flakes as thafe
is, nor is it altogether lb tulfj but is much more clear and tranfoarent,and mueh more curioufly lhaped , and yet may be cleft and flak’d like the o- ther Seknitk, But fourthly, this ftone has a property, which in refpeft of the Jlltcrofcope^ is more notable, and that is, that it exhibits feveral ap- pearances of Golours5 both to the naked Eye, but much more conlpicu- oully to the Mierdfeope ^ for the exhibiting of which , I took a piece of Mufcovy-glafi^ and Iplitting or cleaving it into thin Plates, I found that up . and down in leveral parts of them I could plainly perceive feveral white Ipccks or flaws, and others diverOy coloured with all the Colours of the Rainbow 5 and with the Microjiope I could perceive , that thefe Colours were ranged in rings that incompaffed the white Ipeck or flaw, and were round or irregular, according to the lhape of the fpot Which they termi- nated 5 and the pofition of Colours, in rel|3ed: of one another, was the very lame as in the Rainbow, The conlecution of thofe Colours from the middle of the Ipot outward being Blew, Purple, Scarlet, Yellow, Greeny Blew, Purple, Scarlet, and fo onwards, fometimes half a foore times re- peated,that is,thcre appeared hx,foven,eight,nine or ten feveral coloured rings or lines, each incircling the other, in the lame manner as I have of- ten foen a very vivid Rainbow to have four or five feveral Rings of Co- lours, that is, accounting all the Gradations between Red and Blew for one : But the order of the Colours in thefe Rings was quite contrary to the primary or innermoft Rainbow ^ and the fame with thofo of the focon- dary or outermoft Rainbow , thefe coloured Lines or Irifes^ as I may fo call them , were fome of them much brighter then others , and fome of them alfo very much broader, they being fome of them ten, twenty, nay,
I believe , neer a hundred times broader then others 5 and thofe ufoally were broadifh which were neereft the center or middle of the BaW. And oftentimes I found , that thefe Colours reacht to the very middle of the flaw , and then there appeared in the middfe a very large fpot , for the moft part, all of one colour , which was very vivid , and all the other Colours incompaffing it, gradually afeending, and growing narrower to- wards the edges, keeping the fame order , as in the jeenndafy Rainbow, that is,if the middle were Blew, the next incompaffing it would be a Pur- ple,the third a Red, the fourth a Yellow, &c, as above if the middle were a Red,the next without it would be a YelloW,the third a Green, the fourth a Blew,and fo onward,. And this order it alwayes kept whatfo- ever were the middle Colour.
There was further obfervable in feveral other parts of this Body, ma~ ny Lines or Threads,each of them of fome one peculiar Colour, and thofe fo exceedingly bright and vivid , that it afforded a very picafantobjed
through
MlCROGRAPHIAi
through the Microfcope. Sortie of thefe threads I have oBferved al/b to be pieced or made up of feveral fliort lengths of differently coloured ends (' as I may fb call them ) as a line appearing about two inches long through the Microfeope , has been compounded of about half an inch of a Peach colour, w of a lovely Grafs-green, f of ah inch more of a bright Scarletjand the reft of the line of a Watchet blew. Others of them were much otherwife coloured 5 the variety being almoft infinite. Another dung which is very obfervablej is, that if you find any place where the colours are very broad and confpicuous to the naked eye, you may, by prefling that place with your finger, make the colours change places,and go from one part to another.
'There hone rhanomenon more, which may, if care be ufed^ exhi- bit to the beholder, as it has divers times to me, an exceeding pleafant, and toot lefsinftrudlive Spedacle 5 And that is, if curiofity and diligence beufed , you may fo fplit this admirable Subftance , that you may have pretty large Plates ( in comparifon of thofe fmallefones which you may obferve in the Rings ) that are perhaps an i or a ^ part of an inch over^ each of them appearing through the Mkrofeope moft curioully, intirely^ and uniformly adorned with fome one vivid colour ; this, if examined Vfiththe Mkrofeope , maybe plainly perceived to be in all parts of it e- qually thick. Two, three, or more of thefe lying one upon another, ex- hibit oftentimes curious compounded colours , which produce fuch a Cofnpi^tHm 3 as One would ftarce imagine fhould be the refult of fuch in- gredients : As perhaps a faint yellovo and a blew may produce a very deep pnrple. But when anon we come to the more ftrid examination of thefe Fbanomena^ and to inquire into the caufes and reafons of thefe produfti- cnsjWe fhall,! hope , make it more conceivable how they are produced,; and fhewthemtobc no other then the natural and neceftary effeds ari- lingfrom the peculiar union of concurrent caufes.
Thefe rheenomena being fb various, and fb truly admirable, it will cer- tainly be very well worth our inquiry , to examine the caufes and reafbns of them,and to confider, whether from thde caufes demonftratively evi- denced , may not be deduced the true caufes of the produdion of all kind of Colours. And I the rather now do it , inftead of an Appen- dix or Digreflion to this Hiftory, then upon the occafion of examining the Colours in Peacocks, or other Feathers, becaufe this Sub jed , as it docs afibrd more variety of particular Colours , fb does it affbrd much better wayes of examining each circumftance. And this will be made manifeft to him that confiders , firft , that this laminated body is more Ample and regular then the parts of Peacocks feathers, this confifting on- ly of an indefinite number of plain and fmooth Plates, heaped up, or in- cumbent on each other; Next, that the parts Of this body are rriuch more manageable, to be divided or joyned, then the parts of a Peacocks fea- ther,or any other ftibftance that I know. And thirdly, becaufe that in this; we arc able from a colourlefs body to produce feveral coloured bodies, affording all the variety of Colours imaginable : And feveral others, which the fubfequent Inquir}" will make manifeft.
I To
Micrographia.
To begin therefore^ it is manifeft from Icveral circumftances, that the material caufe of the apparition of thefe feveral Colours , is fome Lamina. or Plate of a tranfparent or pellucid body of a thickncfi very determi- nate and proportioned according to the greater or lefs refradivc power of the pellucid body. And that this is fo.abundance of Inftances and par- ticular Circumftances will make manifeft.
As firfl 3 if you take any fmall piece of the Mufcovy-glafs , and with a Needle , or fome other convenient Inftrument, cleave it oftentimes into thinner and thinner Lamina^ you fhall find, that till you come to a deter- minate thinnefs of them, they fhall all appear tranfparent and colourlefs, but if you continue to I'plit and divide them further, you fhall find at lafV, that each Plate, after it comes to flich a determinate thicknefs, fhall ap- pear moft lovely ting’d or imbued with a determinate colour. further, by any means you fo flaw a pretty thick piece, that one part does begin to cleave a little from the other, and between thofe two there be by any means gotten fome pellucid medium, thole laminated pellucid bodies that fill that fpace, fhall exhibit feveral Rainbows or coloured Lines, the co- lours of which will be difpofed and ranged according to the various thicknefles of the feveral parts of that Plate. That this is fo, is yet fur- ther confirmed by this Experiment.
Take two fmall pieces of ground and polifht Looking-glafs-plate, each about the bignefs of a fhilling, take thefe two dry , and with your fore-fingers and thumbs prefs them very hard and clofe together,and you fhall find; that when they approach each other very near, there will ap- pear feveral Irijes or coloured Lines, in the fame manner almoft as in the Mufcovy-glafs and you may very eafily change any of the Colours of any part of the interpofed body, by preffing the Plates clofer and hard- er together,or leaving them more lax that is, a part which appeared co- loured with a red, may be prefently ting’d with a yellow, blew, green, purple , or the like , by altering the appropinquation of the terminating Plates.Now that air is not neceflary to be the interpofed body, but that any other tranfparent fluid will do much the fame, may be tryed by wet- ting thofe approximated Surfaces with Water , or any other tranfparent Liquor, and proceeding with it in the fame manner as you did with the Air ^ and you will find much the like effed: , only with this difference, that thofe compreff: bodies, which differ moft, in their refraftivc quality, from the compreffing bodies , exhibit the moft ftrong and vivid tin- ftures. Nor is it neceflary , that this laminated and tingd body fbould be of a fluid fubftance , any other fubftance , provided it be thin enough and tranfparent, doing the fame thing : this the Lamina oi our Mufeovy- glafs hint 5 but it may be confirm’d by multitudes of other Inftances.
Andfirft, we fhall find, that even Glafs it felf may, by the help of a Lamp, be blown thin enough to produce thefe Phenomena of Co- lours : which Phanomena accidentally happening , as I have been attempting to frame fmall Glafles with a Lamp , did not a little furprize me at firft , having never heard or feen any thing of it before 5 though afterwards comparing it with the Phanemena , I had often
obferved
]\4iCR0GRAi*HiA.
obferved in thofe Bubbles which Children ufe to make with Soap-waiter, I did the lels wonder 5 efpecially when upon Experiment I found, I Was able to produce the fame Fhanoixeiia in thin Bubbles rhade with any other tranfparent Subftance. Thus have I produced t hem with Bubbles of Vitch.^ U:o^n^Colophony^T7irpent7Ke^ Sohftivns
Arabick^ in watery any glutinvm Liquor,as Wurt^WineySpirit of Wme^ Oyl of Turpentine^ Glare of Snails^ 8cc.
It would needlefs to enumerate the feveral Inftances thefo being enough to (hew the generality or univerlality of this propriety. Only I muft not omit, that we have inftancesalfo of this kind even in metalline Bodies and animal 5 for thole feveral Colours which are oblerved to fol- low each other upon the polilht liirface of hardned Steel, when it is by a fuflicient degree of heat gradually tempered or foftened , are produced from nothing elfe but a certain thin Lamina of a t^itrum or vitrifkd part of the Metal, which by that degree of heat, and the concurring aftkm of the ambient Air,is driven out and fixed on the fUrfaceof the Steel.
And this hints to me a very probable ( at leaft, if not the true) caule of the hardning and tempering of Steel, which has not, I think, been yet gi ven,nor, that I know of,been lb much as thought of by any. And that is this, that the hardnels of it arifes trom a greater proportion of a vitrifi-^ ed Subftance interfperled through the pores of the Steel. And that the tempering or Ibftning of it arifes frt)m the proportionate or (mailer parcels of it left within thofe pores. This will feem the more probable , if we conlider thefe Particulars.
Firft, That the pure parts of Metals are of themfelves very flexible and tujfy that is, will indure bending and hammering, and yet retain their continuity.
Next, That the Parts of all vitrified Subftances, as all kinds of Glals, the Scoria of Metals, <&c. are very hard, and allb very brittle, being neb ther flexible nor malleable ^ but may by hammering or beating be broken into fmall parts or powders.
Thirdly ,That all Metals ( excepting Gold and Silver , which do not lb much with the bare fire, unlels affifted by other feline Bodies ) do more or left vitrifie by the ftrength of fire, that is, are corroded by a fe- line Subftance, which I elfewhere (hew to be the true caufe of fire 5 and are thereby, as by feveral other Menjiruums^comerted into Scoria 5 And this is called, calcining o£thsm^ by Chimifts. Thus Iron and Copper by heating and quenching do turn all of them by degrees into Scoria^ which are evidently Subftances , and unite with Gla(s , andareeafily
fufible 5 and when cold, very hard, and very brittle.
Fourthly, Thatmoft kind of Vitrifications or Calcinations ^Lvcm^dthy Salts, uniting and incorporating with the metalline Particles. Nor do I know any one calcination wherein a Saline body may not, with very great probability, be feid to be an agent or coadjutor.
Fifthly, That Iron is converted into Steel by means of the incorpofa- tion of certain falts, with which it is kept a eertain time in the fire.
52
Mi CROGRAP HIA.
Sixthly, That any Iron may, in a very little time, be cafe hardned^ as the Trades-men call it, by cafing the iron to be hardned with clay, and putting between the clay and iron a good quantity of a mixture otVrwCy Soot^Sea-Jalty Sind Horfes hoofs (all which contein great quantities of Sa- line bodies) and then putting the cafe into a good ftrong fire, and keep- ing it in a confiderable degree of heat for a good while, and afterwards heating, and quenching or cooling it fuddenly in cold water.
Seventhly ,That all kind of vitrify ’d fubftancesjby being fuddenly cool’d, become very hard and brittle. And thence arifes the pretty Pheenomena of the Glafs Drops, which I have already further explained in its own place.
Eighthly, That thofe metals which are not fb apt to vitrifie, do not ac- quire any hardnefs by quenching in water, as Silver, Gold, Sec.
Thcfe confiderations premis’d, will, I fuppofe, make way for the more eafie reception of this following Explication of the Ph<emmena of hardned and temper'd Steel. That Steel is a fubftance made out of Iron, by means of a certain proportionate Vitrification of feveral parts, which are fb cu- rioufly and proportionately mixt with the more tough and unalter’d parts of the Iron, that when by the great heat of the fire this vitrify ’d fub- ftance is melted, and confcquently rarify’d, and thereby the pores of the Iron are more open, if then by means of dipping it in cold water it be fuddenly cold, and the parts hardned, that is, ftay’d in that fame de- gree of Expanfion they were in when hot, the parts become very hard and brittle, and that upon the fame account almoft as fmall parcels of glafs quenched in water grow brittle, which we have already explicat- ed. If after this the piece ofSteel be held in fbme convenient heat,till by degrees certain colours appear upon the furface of the brightned metal, the very hard and brittle tone of the metal, by degrees relaxes and be- comes much more tough and fbft 5 namely, the adtion of the heat does by degrees loofen the parts of the Steel that were before ftreached or fet atilt as it were, and ftayed open by each other, whereby they become relaxed and fet at liberty, whence fbme of the more brittle interjacent parts arc thruft out and melted into a thin skin on the furface of the Steel, which from no colour increafes to a deep Purple, and fb onward by thele gradations or confecutions, White^ Tellow^ Orange^ Minium^ Scarlet^ Purple^ BlevofiVatchet^ &c. and the parts within are more conveniently, and pro- portionately mixt 3 and fb they gradually fubfide into a texture which is much better proportion’d and clofer joyn’d, whence that rigidneffe of parts ceafes, and the parts begin to acquire their former du&il- mfs.
Now,that ’tis nothing but the vitrify’d metal that fticks upon the furface of the colour’d body, is evident from this, that if by any means it be fera- ped and rubb’d ofl^the metal underneath it is white and clear^and if it be kept longer in the fire, fb as to increafe to a confiderable thicknefs, it may, by blows, be beaten offin flakes. This is further confirm’d by this obkrvable, that that Iron or Steel will keep longer from rufting which is covered with this vitrify’d cafe : Thus alfb Lead will, by degrees, be
all
Ml CROC RAP HIA.
all turn’d into a litharge, for that colour which covers the top being fcum’d or Ihov’d afide, appears to be nothing: elfe but a litharge or vitrify ’d Lead.
This is oblervable allb in forae fort , bn Brals, Copper, Silver, Gold^ Tin, but is moft confpieuous in Lead : all thofe Colours that cover the Kurface of the Metal being nothing elfe , but a very thin vitrifi’d part of the heated Metal.
The other Inftance we have, is in Animal bodies, as in Pearls, Mother of Pearl-lhels, Oyfter-fliels, and almoft all other kinds offtonyfhels whatfoever. This have I alfo Ibrhetimes with pleafure obferv d even in Mufclesand Tendons. Further, if you take any glutinous fubftance and run it exceedingly thin upon the (urface of a linooth glals or a po- liiht metaline body, you ftiall find the like effeds produced ; and in general, wherelbever you meet with a tranfparent body thin enough, that is terminated by refleding bodies of differing refradions from it, there will be a produdion of thefe pleafing and lovely colours.
Nor is it neceflary, that the two terminating Bodies fhould be both of the fame kind, asmay appear by the vitrified Lamince on Steely Lead^ and other Metals,one furface of Larnime is contiguous to thelurfaee of the Metal, the other to that of the Air.
Nor is it neceflary, that thefe colour’d Lamina fhould be of an even thicknefs, that is, fhould have their edges and middles of equal thicknefs, as in a Looking-glafs-plate, which circumftance is only requifite to make the Plate appear all of the fame colour 5 but they may refemble a Lens^ that is, have their middles thicker then their edges 5 or elfe a double con- cave^ that is, be thinner in the middle then at the edges 5 in both which cafes there will be various coloured rings or lines,with differing confecu- tions or orders of Colours , the order of the firft from the middle out- wards being Red, Yellow, Green, Blew. &c. And the latter quite con- trary.
But further, it is altogether neceflary, that the Plate, in the places where the Colours appear, fhould be of a determinate thicknefs : Firft, ft inuft not be more then fuch a thicknefs, for when the Plate is increafed to ftich a thicknefs , the Colours ceafe , and befides , I have feen in a thin piece of Mufiovy-glafs^ where the two ends of two Plates, which appear- ing both fingle , exhibited two diftinft and differing Colours , but in that place where they were united, and conftituted one double Plate (as I may call it) they appeared tranfparent -and colourlefs. Nor, Se- condly , may the Plates be thinner then fiich a determinate cize 5 for we alwayes find, that the very outmoft Rim of thefe flaws is terminated in a white and colourlefs Ring.
Further, in this Prod u6f ion of Colours there is no need of a determi- nate Light of fuch a bignefs and no more , nor of a determinate pofition of that Light,that it fhould be on this flde,aiid not on that fide ^ nor of a terminating fhadow, as in the Prifme, and Rainbow, or Water-ball : for we find, that the Light in the open Air, either in or out of the Sun-beams, and withm a Room, either from one or many Windows, produces much
Micrographia.
the lame effed : only where the Light is bright eft, there the Colours tire moft vivid. So does the light of a Candle , colleded by a Glafs-ball. And further , it is all one whatever fide of the coloured Rings be to- wards the lights for the whole Ring keeps its proper Colours from the middle outwards in the fame order as I before related , without varying at all, upon changing the pofition of the light.
But above all it is moft oblervable, that here are all kind of Colours generated in a pellucid body,where there is properly no liich refradion as Des Cartes fuppoles his Globules to acquire a verticity by : For in the plain and even Plates it is manifeft, that the fecond refradion ( accord- ing to Des Cartes his Principles mxhQ fifth Se&ion of the eighth Chapter of his Meteors ) does regulate and reftore the liippoled turbinated Glo- bules unto their former uniform motion. This Experiment therefore will prove liich acne as our thrice excellent Verulam calls Experimentum Cm- ciSj lerving as a Guide or Land-mark , by which to dired our courle in the fearch after the true ca ale of Colours. Affording us this particular negative Information, that for the produdion of Colours there is not ne- cellary either a great refradion, as in the Prifme 5 nor Secondly, a deter- mination of Light and lhadow , liich as is both in the Prilme and Glals- ball. Now that we may lee likewile what affirmative and pofitive Inftru- dion it yields,it will be neceflary, to examine it a little more particularly and ftridly 5 which that we may the better do , it will be requifite to premife fomewhat in general concerning the nature of Light and Refra- dion.
And firft for Light,it leems very manifeft, that there is no luminous Bo-^ dy but has the parts of it in motion more or left.
Firft, That all kind of fiery burning Bodies have their parts in motion, I think, will be very eafily granted me. That the Jpark^ ftruck from a Flint and Steel is in a rapid agitation , I have ellewherc made probable. And that the Parts of rotten Woody otten Fifif the like, are allbin mo- tion, I think, will as eafily be conceded by thofe, who confider,that thole parts never begin to Ihine till the Bodies be in a ftate of putrefadion 5 and that is now generally granted by all , to be cauled by the motion of the parts of putrifying bodies. That the Bononian Jione Ihines no lon- ger then it is cither warmed by the Sun-beams, or by the flame of a Fire or of a Candle, is the general report of thofe that write of it, and of others that have feen it. And that heat argues a motion of the internal parts, is ( as I laid before ) generally granted.
But there is one Inftancemore, which was firft lhewntotheiff^j'^/«y<7- ciety by Mr. Clayton a worthy Member thereof, which does make this Aft lertion more evident then all the reft ; And that is. That a Diamond be- ing rub'd^ oiheatedmtliQ dark, Ihines for a pretty while after, lb
long as that motion, which is imparted by any of thole Agents, remains fin the fame manner as a Glaft,rubb’d,ftruck3or(by a means which I lhall ellewhere mention ) heated, yields a Ibund which lafts as long as the vi- brating motion of that fonorous body ) feveral Experiments made on which Stone, are fince publilhed in aDilcourle of Colours, by the truly
honou-
M
ICROGRAPHIA.
honourable Mr. Boyle. What may be laid of thole Ignes fatni that ap- pear in the night,! cannot lb well affirm, having never had the opportuni- ty to examine them my felf, nor to be inform’d by any others that had oblerv’d them : And the relations of them in Authors are fo imperfcd:, that nothing can be built on them. But I hope I fhall be able in another place to make it at leali very probable, that there is even inthofe alfoa Motion which caiifes this efieft. That the ihining of Sea-water proceeds from the fame caufe, may be argued from this. That it fhines not till ei- ther it be beaten againft a Rock, or be Ibme other wayes broken or agi- tated by Storms, or Oars, or other bodies. And that the A- nimal Energyes or Spirituous agil parts are very a dive in Cats eyes when they fhine, feems evident enough, becaufe their eyes never Ihine but when they look very intently either to find their prey, or being hunted in a dark room, when they feek after their ad verlary, or to find a way to elcape. And the like may be laid of the fhining Bellies of Gloworms^ fincetis evident they can at pleafure either increafe or extinguifh that Radiation.
It would be fomewhat too long a work for this, place Zetctically to examine, and pofitively to prove, what particular kind of motion it is that muff be the efficient of Light 5 for though it be a motion, yet ’tis not every motion that produces it, fince we find there are many bodies very violently mov’d, which yet afford not fuch an effed 5 and there are other bodies, which to our other fenfes, i'eem not mov’d lb much, which yet fhine. Thus Water and quick-lilver, and moft other liquors heated, fhine not 5 and leveral hard bodies, as Iron, Silver, Brals, Cop- per, Wood, though very often ftruck with a hammer, fhine not pre- fently, though they will all of them grow exceeding hot 5 whereas rot- ten Wood, rotten Fifh, Sea water, Gloworras, have nothing of tan- gible heat in them, and yet ( where there is no ftronger light to affed the Senforyjthey fhine fome of them lb Vividly, that one may make a fhift to read by them.
It would be too long, I fay, here to infert the difcurfive progrefs by which I inquir’d after the proprieties of the motion of Light, and there- fore I fhall only add the refult.
And,Firft,I found it ought to be exceeding fuch as thofe moti-
ons fermentation and putrefailion^ whereby, certainly, the parts are exceeding nimbly and violently mov’d 5 and that, becaufe we hnd thofe motions are able more minutely to fhatter and divide the body, then the moft violent heats or menjirmms we yet know. And that fire is nothing elfe but fuch a dijjdlution of the Burning body, made by the moft univer^ fal menjirnum of all jnlphnreous bodies^ namely, the Air, we fhall in an other place of this Tradate endeavour to make probable. And that, in all extreamly hot fhining bodies, there is a very quick motion that caufes Light, as well as a more robuft that caufes Heat, may be argued from the celerity wherewith the bodyes are difiblv’d.
Next, it muft be a Vibrative motion. And for this the newly mention’d Diamond affords us a good argument 3 fince if the motion of the parts did
not
Micrograp hia.
not returnjthe Diamond muft after many rubbings decay and be waftedi but we have no reafon to fufped the latter, elpecially if we confider the exceeding difficulty that is found in cutting or v/earing away a Di- amond. And a Circular motion of the parts is much more improbable, fince, if that were granted,and they be fuppos’d irregular and Angular parts, I fee not how the parts of the Diamond ihould hold fo firmly to- gether, or remain in the lame lenfible dimenfions, which yet they do. Next, if they be Globular^ and mov’d only with a turbinated motion, I know not any caufe that can imprefs that motion upon the pellucid me- dium^ which yet is done. Thirdly, any other irregular motion of the parts one amongft another, muft necelferily make the body of a fluid confidence, from which it is far enough. It muft therefore be a Vibra-^ ting motion.
And Thirdly, That it is a very fiort vibrating motion^ I think the in- ftances drawn from the Ihining of Diamonds will alfo make probable. For a Diamond being the hardeft body we yet know in the World, and confequently the leaft apt to yield or bend, muft confequently allb have its vibrations exceeding ftiort.
And thefe, I think, are the three principal proprieties of a motion, re- quifite to produce the effect call’d Light in theObjed.
The next thing we are to confider, is the way or manner of the traje- Gion of this motion through the interpos’d pellucid body to the eye : And here it will be eafily granted,
Firft, That it muft be a body jufeeptibk zvid impartible of this motion that will deferve the name of a Tranfparent. And next, that the parts of filch a body muft be Homogeneous^ or of the lame kind. Thirdly, that the conftitution and motion of the parts muft be fuch, that the appulle of the luminous body maybe communicated or propagated through it to the greateft imaginable diftance in the leaft imaginaMe time 5 though I lee no reafon to affirm, that it muft be in an inftant ; For I know not any one Experiment or obfervation that does prove it. And, whereas it may be ob jeded. That we fee the Sun rifen at the very inftant when it is above the fenfible Horizon, and that we fee a Star hidden by the body of the Moon at the lame inftant, when the Star, the Moon, and our Eye are all in the fame line 3 and the like Obfervations, or rather liippofitions, may be urg’d. I have this to anfwer. That I can as eafily deny as they affiimj for I would fain know by what means any one can be afliircd any more of the Affirmative, then I of the Negative. If indeed the propagation were very flow, tis poflible Ibmething might be dilcovered by ^lyp- les of the Moon 3 but though we fhould grant the progrefs of the light from the Earth to the Moon, and from the Moon back to the Earth a- gain to be full two Minutes in performing, I know not any poflible means to dilcover it 3 nay, there may be Ibrae inftances perhaps of Ho- rizontal Eclyples that may feem very much to favour this fuppofition of the flower progreflion of Light then moft imagine. And the like may be faid of the Eclypfes of the Sun, &c* But of this only by the by. Fourthly, That the motion is propagated every way through an Homo-
geneous
MlCROGRAi* Hi A.
genedus tjftdinm by direB or Jiraight lines extended every way like Rays from the center of a Sphere. Fifthly, in an Ho/fwgeneous medium this mo- tion is propagated every way with equal velocity^ whence neceilarily eye- ry pulfi or vitraticn of the lurhinous body will generate a Sphere, which will continually incrcale, and grow bigger, juft after the fame manner (though indefinitely (wifter) as the waves or rings on the furface of the water do (Well into bigger and bigger circles about a point of it, where, by the finking of a Stone the motion was begun, whence it neceflarily fol- lows, that all the parts of thefe Spheres undulated through an Homogene~ OKS tftedium cut the Rays at right angles.
But becaule all tranfparent mediums not Homogeneous to one an- other,thercfore we will next examine hoW this pulfe or motion will be propagated through differingly tranfparent me^ums. And here, ac- cording to the moft acute and excellent Philolbpher Des Cartes^ I fup- pole the fign of the angle of inclination in the firft medium to be to the fign of refiradion in the fecond. As the denfity of the firft, to the denfity of the feCond. By denfity, I mean not the denfity in relped of gravity (with Which the refradions or tranfparency of mediums hold no proportion) butinrelpedonely to the trajeBiono^ the Rays of light, in which refped they only differ in this 5 that the one propagates the pulle more eafily and weakly, the other more (lowly, but more ftrongly. But as for the pulfes themfelves, they will by the refradion acquire another propriety, which we (hall now endeavour to explicate.
Wc will fuppofe thcreft)re in the firft Figure AC F D to be a phyfical Ray, or AB C and D E F to be two Mathematical trajeBed from a very remote point of a luminous body through an Homogeneous tranlpa- tehi medium LL L, and D A, E B, FC, to be finalh portions of the or- bicular impulfcs which muft therefore cut the Rays at right angles 5 thefe Rays meeting with the plain furface N O of a medium that yields an eafier tranjtus to the propagation of light, and falling obliquely on it, they will in the medium M MM be refraded towards the perpendicular of the furface. And becaufe this medium is more eafily trajeBed then the former by a third, therefore the point C of the orbicular pulfe F C will be mov’d to H four (paces in the fame time that F the other end of it is mov’d to C three (paces, therefore the whole refraded pulfe G H (hall be oblique to the refraded Rays C H K and G 1 5 and the angle G H G (hall be an acute, and fb much the more acute by how much the greater the refiradion be, then which nothing is more evident, for the fign of the inclination is to be the fign Of refradion as G F to T C the diftance be- tween the point G and the perpendicular from G on C K, which being as four to three, H C being longer then G F is longer allb then T G, there- fore the angle G H C is left than G T C. So that henceforth the parts of the pulfes GH and I Kate mov’d afeew, or cut the Kzys at ^oblique angles; ^ ^ \ ' ^ ;
It is nOt my bufidels in this place to fet down the feafons why this or that body fhould impede the Rays more, others I'efs : as why W^erfhould tranfmit the Rays more eafily, though more weakly than air. Onely thus
R much
^8 MiCROGRAPHIA.
much in general I (hall hintjthat I fuppofe the medium M M M to have lefs of the trarirparent undulating fubtile matter, and that mattey to he le(s implicated by it, whereas LLL I fuppofe to contain a greater quantity of the fluid undulating (ubftance,and this to be more iipplicated with the particles of that medinm.
But to proceed, the fame kind of obliquity of the Pulfesand Rayj \yill happen ?il(b when the refraftion is made out of a more eafic into arnere difficult mediu 5 as by the calculations of G Q & C S R which are refrgfted from the perpendicular. In both which calculations tis <^bvions to obferve^ that always that part of the Ray towards which the refradipn is made has the end of the orbicuUr pulfe precedent to that of the other fide, ^nd always,the oftner the refraftion is made the fame way, Or the greater rh^ Angle refra^ion is, tHe more is this unequal progrcls. So that having found this odd propriety to be an inleparable concomitant of a reffafted Ray, not ftreightned by a contrary refraftion, we will next ei^iamine the refradiions of the Sun-beams, as they are fuffefd onely to pals through a finall paflage, obliquely out of a more difficult,into a more eafie medium.
Let us (uppole therefore ABC in the fecond Figure to reprelent a large Chimied Ghfs-body about two foot long, filled with very fair Wa^ ter as high as A B, and inclin’d in a convenient pofture with B towards the Sun : Let us further luppofe the top of it to be cover’d with an eo^us body, all but the hole 4 through which the Sun-beams are fuffer’d to pafi into the Water,and are thereby refrafted toe d e/jagainfi: which part, if a Paper be expanded on the outfide, there will appear all the co- lours of the Rain-bow, that is, there will be generated the two principal colours, Scarlet and^/»e, and all the ones which arife frorp
the compofition and dilutings of tfiefe two, that is, c d, (hall e^thibit a Sear let ^ which toward d is diluted into a Tel/ow 5 this is the refrgdi:ipn of the Ray, which comes from the underfide of the Sun ^ and the Ray
ef (hall appear of a deep which is gradually towards e diluted in- to a pale Watchet-blue. Between d and e the two dUnted colours. Blue and Tel/ow are mixt and compounded into a Green 5 and this I iipagine to be the reafon why Grcm is fo acceptable a colour to the eye, and that either of the two extremes are, if intenfe, rather a little offenfive, narne^ ly, the being plac’d in the middle between the two extremes, and epnt- pjQunded outof boththofe, diluted alfo, or (gmewhat qualifi’d, for the eompofition^ arifing from the mixture of the two’ extremes undilHtedi makes a fwrp/a, which though it be a lovely eolourjand pretty aeeeptabl^ to the eye, yet is it nothing comparable to tho ravifhing whb
which a eUrious and well tempered Green affe^s the eye, If rSPlPving the Paper, the eye be plac’d againft f d^ it wifi perceive the fower fide of the ^un (or a Candle at night which is much better, becaufe it ofiend? not the eye, and is more cafily manageable) to be of a deep Reds and if againft e f it will perceive the upper part of the luminous body to be of a deep Mhe'^ andthefe colours will appear deeper and deeper, accord- ing as the Rays from the luminous body fall more Mquely on the fi?r^ face of the Water, and thereby (life a greater refra^lipst, and the
more
Ml CROC RA P H I A. 0
illore diftind, the further c def is removed from the trajefting ho!e.
So that upon the whole, we flhall find that the reafon of the rh£f2ome~ na feems to depend upon xhtobliqnity of the orbicular pdfeyo the Lines of Radiatiomahd in particular,that the Ray e d which confiitutes the^e^r- let has its inner parts, namely thofe which are next to the middle of the luminous body, precedent to the outermoft which are contiguous to the datk and unradiaiiug fkie. And that the Ray ef which gives a Blue^ has its outward part,namely, that which is contiguous to the dark ikie prece- dent to the pulfe from the irinermofi:, which borders on the bright areti of the luminous body.
We may obferve further, that the caule of the diluting of the colours to- wards the middle, proceeds partly from the widenefs of the hole through which the Rays pafs, whereby the Rays from feveral parts of the lumi- nous body, fall upon many bf the fame parts between c and/ as is more manifeft by the Figure : And partly alfo from the nature bf the refraifliorr • it felf, for the vividnefs or ftrength of the two terrhinhting colours, arifing ♦ chiefiy as We have feen, from the very great difference that is betwixt the outfides of thofe oblique undulations & the dark Pvays circumambient,and that difparity betwixt the approximate Rays,decay ing gradually : the fur- ther inward toward the middle of the luminous body they are remov’d, the more muff the colour approach to a white of an undifturbed light.
Upon the calculation of the refradtion and refledtion froin a Ball o^“ Water or Glafs,we have much the fame Phenomena obliquity of
the undulation in the fame mai^ner as we have found it here. Which, be- caufe it is very much to our prefent purpofe, and affords fuch an Injiancia, cruck^ as no one that I know has hitherto taken notice of, I fhall further examine. FOr it docs very plainly and pbfitively diftiriguifh, and fbew, which of the two Bypothefes^t\t.\itv the Cartefia'n or this is to be followed, by affording a generation of all the colors in the Rainbow,where accord- ing to the Cartefian Principles there fhould be none at all generated. And fecbndly, by affording an inifance that does more clofely confine the caufe of thefe Phenomena of colours to this prefent Hypothecs.
And firfl:,for the Cartefian have this to objed againft it, That Whereas he fays (fAfeteorum Cap,8.Setl.^.^Sed judicabam unicam(refra&idne fcilicet) ad minima requiri^C^ quidem talem nt ejus effeUus alia contraria (refraBi- one^non dejiruatur i Nam experiehtia d'oeet fiji/perfi'eies N M N P (nempe refringentes') ParalleU forent^ radios tahtundem per alteram iterum ereBos quantum per unamfrangerenturyiullos colores depiBurbs ^ This Principle of his holds true indeed in a priftne where the refradfing fiirfaces are plain, butiscontradidfedby theBallor Cylinder, Whether of Water orGlafs, where the refradfing furfaces are Orbicular or Cylindrical. For if we ex- amine the paffage bf any Globule or Ray of the primary Irkyxo. fhall find it to pafs out of the Ball or Cylinder again, with the fame inclination and refradfion that it enter’d in withall, and that that laft refradtion by means of the intermediate refiedfion fhall be the fame as if without any refledtion at all the Ray had been twid:e refradted by twb Parallef furfaces;
K 2 And
Micrographia.
And that this is true, not onely in one, but in every Ray that goes to the conftitution of the Primary Iris^ nay, in every B.ay, that fufFers only tv^^o refraftions.and one refle6don,by the lurface of the round body, we (hali prefentiy fee moft evident, if we repeat the Cartejian Scheme^ men- tioned in the tenth SeUion of the eighth Chapter Meteors^ where E F K N P in the third Figure is one of the Rays of the Primary Iris, twice refradted at F andN, and once retledbed at K. by thefurface of the VVarcr-ball. For, firft it is evident, that R F and RN are equal, becaufe R N being the refiedted part of R F they have both the lame inclination on the furface R that is the angles F R T, and N R V made by the two Rays and the Tangent of R arc equal,which is evident by the Laws of re- flexion 5 whence it will follow alfo, that R N has the fame inclination on the furface N, or the Tangent of it X N that the Ray R F has to the lur- face F, or the Tangent of it F Y, whence it muft neceflarily follow,that the refraXions at F andN are equal, that is, RF E and RN P are equal. Now, that the lurface N is by the refieXion at R made parallel to the lur- face at F, is evident from the principles of refleXion 5 for refleXion being nothing but an inverting of the Rays, if we re-invertthe Ray RN P, and make the fame inclinations below the line T R V that it has above, it will be moft evident, that R H the inverle of R N will be the continuation of the line F R, and that L H I the inverfe of O X is parallel to F Y. And HM the inverle of N P is Parallel to EF for the angle R H I is equal to R N O which is equal to R F Y, and the angle R H M is equal to R N P which is equal to R F E which was to be proved.
So that according to the above mentioned Caritfian principles there fhould be generated no colour at all in a Ball of Water or Glals by two refraXions and one refleXion, which does hold moft true indeed, if the liirfaccs be plain, as may be experimented with any kind of prilme where the two refi'aXing lurfaces are equally inclined to the refleXing , but in this the Th^nomena. are quite otherwile.
The caule therefore of the generation of colour muft not be what Des Cartes afligns, namely, a certain rotation of the which are
. the particles which he fuppoles to conftitute the Pelluad medium^ But Ibmewhat elle, perhaps what we have lately luppofed, and lhall by and by further profecute and explain.
But,Rrft I lhal! crave leave to propound Ibme other difficulties of his, notwithftanding exceedingly ingenious Hypothefis. which I plainly confefe to me feem fuch, and thofeare,
Firft, if that light be (as is affirmed, 'Diopt. cap. i. §. 8.) not fo pro- perly a motion,'as anaXion or propenfion to motion, I cannot conceive how the eye can come to be lenlible of the verticity of a Globule^ which is generated in a drop of Rain, perhaps a mile off from it. For that Globule is not carry ’d to the eye according to his formerly recited Principle^ and if not fo,I cannot conceive how it can communicate its rotation^ox circular motion to the line of the Clobuleshtx^N^tTi the drop and the eye. It can- not be by means of every ones turning the next before him ^ for iffo, then onely all the that are in the odd places muft be turned the lame
way
Scherrb:Vl.
I
. 1
I /
i
i
A \
M i CROC RAP HiA.
way with the firft, namely, the 3. 5. 7. 9, but all the Globule f
interpofited betweenthemintheevenplaces^ namely ,the 2.4.6.8.10.^"^* niuft be the quite contrary 5 whence, according to the Cartefian Hj/potkeJls^ there muft be no diftindi: colour generated, but a confufion. Next, fince th.Q C artejlm Globuli arcfuppos'd (Priudfiorum Vhilofiph. Part. 3. $.86.} to be each of them continually in motion about their centers, I cannot conceive how the eye is able to diftinguifti this new generated motion from their former inherent one, if I may fo call that other wherewith they are mov’d or turbmated^ from fome other caufe than refradion. And thirdly, I cannot conceive how thefe motions Ihould not happen fome- times to oppofe each other, and then, in dead of a rotation^ there would be nothing but a dired motion generated, and confequently no Colour.
And fourthly, I cannot conceive, how by the Cartefian Hypothejis it is pof lible to give any plaufible reafonof the nature of the Colours generated in the thin Um7f7£ of thefe our Microfcopical Ohfervatious 5 for in many of thefe, the refrading and refleding furfaces are parallel to each other, and confequently no rotation can be generated, nor is there any neceffity of a fhadow or termination of the bright Rays, fuch as is fuppos’d (chap. 8.
§.5. Etpreterea objervavi umbram quoqm^aut limitationem lumink requiri : and chap. 8. §. 9. J to be neceflary to the generation of any diftind co- lours 5 Befides that, here is oftentimes one colour generated without any of the other appendant ones, which cannot be by the Cartejian Hy- pothecs.
There muft be therefore fome other propriety of refradion that caules colour. And upon the examination of the thing, I cannot conceive any one more general, infeparable, and fufficient, than that which I have be- fore afiign’d. That we may therefore fee how exadly our Hypothecs agrees alfo with the of the refrading round body, whether
Globe or Cylinder ^ we fhall next fubjoyn our Calculation or Examen of it.
And to this end, we will calculate any two Rays : as for inftance 5 let schtm. E F be a Ray cutting the Radius C D (divided into 20. parts) in C 1 6. parts diftant from C, and ef another Ray, which cuts the fame Radius in^ 17. parts diftant, thefe will be refraded to K and 4? and from thence refiededtoN and », and from thence refraded toward P and there- fore the ArchF/ will be 5.*^ 5'. The Arch F K to6.'^ 30'. the Arch/ 4 loi.** 2'. The line F G 6oco.and/'_§ 5267. therefore bf. 733. therefore F c 980, almoft. The line F K 1 6024. and f 5436. therefore Nd 196. and n 0 147 almoft, the line Nn 1019 the Arch N n 5.*^ 51'. therefore the Angle N»i?is 54,*^ 43', therefore the Angle N is 139.“^ 56'. which is almoft 50.^^ more than a right Angle.
It is evident therefore by this Hypothejis^ that at the fame time that ef toitches / EF is arrived at c. And by that time e fh^n is got to E F K N is got to and v/hen it touches N, the pulfe of the other Ray is got to o. and no farther, which is very fliort of the place it fhould have arriv’d to,to make the Ray np to cut the orbicular pulfe. N ^ at right Angies i therefore the Angle is an acute Angle, but the quite con- trary
62
Ml C ROG R AP HIA.
trary of this will happen, if ly.and i8.bc calculated in ftcad of i6.and 17.- both which does moft exadly agree with the Thtemt^ena : For if the Sun, or a Candle (which is better) be placed about E e, and the eye about the Rays E F ef at 16. and 17. will paint the fide of the luminous objeift toward » p Blue^and towards N P Red. But the quite contrary will happen when E F is 17. and ef 18. for then towards N P (hall be a Blue^ and towards a Red^ exadtly according to the calculation. And there appears the Blue of the Rainbow, where the two Blue fides of the two linages unite, and there the Red where the two Red fides unite, that is, where the two Images arc juft difappearing 5 which is, when the Rays E F and N P produc’d till they meet,make an Angle of about 41. and an half 5 the like union is there of the two Images in the Produftion of thie SccundaYy tris^ and the lame caufcs, as upon calculation may appear 5 onely with this difterehce, that it is fomewhat more faint, by reafon of the duplicate refledlion, which does always weaken the impulfe the oftner it is repeated.
Now, though the lecond refraction made at N » be convenient, that if, do make the Rays glance the more, yet is it not altogether requifite 5 for it is plain from the calculation, that the pulfc dnxi fufliciently oblique to the Rays K N and wel as the pulfejf c is oblique to the Rays F K &/ And therefore if a piece of very fine Paper be held clofe againft N n and the eye look on it cither through the Ball as from D, or from the other fide, as from B. there ftiall appear a Rainbow, or colour’d line painted on it with the part toward X appearing Red., towards O, Blue 5 the lame allb Ihall happen, if the Paper be placed about K for towards T ftiall ap- pear a Red^ and towards V a Blue^ which does exaCtly agree with this my Hypothejis^ as upon the calculation of the progrefs of the pulfe will moft: cafily appear.
Nor do thefe two obfervations of the colours appearing to the eye a- bout/? differing from what they appear on the Paper at N contradift each other ^ but rather confirm and exaCHy agree with one another, as will be evident to him that examines the rcalons let down by the ingenious. Des Cartes in the 12. Se&. of the 8. chapter of hk Meteors^ where he gives the true reafon why the colours appear of a quite contrary order to the eye, to what they appear’d on the Paper if the eye be plac’d in fteedofthe Paper : And as in the Prifme, lb alfoin the Water, Drop, or Globe the Vhecnomena and realbn are much the lame.
Having therefore ftiewn that there is fuch a propriety in the prifme and water Globule whereby the pulfe is made oblique to the progreflive, and that lb much the more, by how much greater the refraCiion is, I Ihall in the next place confider, how this conduces to the production of co- lours, and what kind ofimprefiion it makes upon the bottom of the eye, and to this end it will be requifite to examine this Hypothefs a little more particularly.
Firft therefore, if we confider the manner of the progrefs of the pulle, it will feem rational to conclude, that that part or end of the pulfe which precedes the other,muft neceflarily be fomwhat more obtimdedfix impeded
by
Ml GROG RAP HI A.
tiy the refinance of the tr^nfparent medium^ than the other part or end of h which is iubrequentj \vhofe way is, as it wete. prepared by the other j eipecially if the adjacent fmdnm be not in the fame manner enlightned Of agitated. And therefore(in thp fourth Figure of the fi^th Icpmfm)thG Ray AAAHB will have its fido HH more deadned by the refiftance of the dark or quiet medium P P Whence there will be a kind of dead-
nefs fuperinduc'd on the fid? H H which will continually incieafe from B, and firike deeper and deeper into the Ray by the line B R ^ Whence ^all the parts of the triangle, R B H O will be of a dead Blue colour, and ib much the deeper, by how much the nearer they lie to the line B H H, whiohi^moR deaded or impeded, and fo much the more ddute^ by how mnch the nearer it approaches the line B R. ISext on the other fide of the Ray A A N, the end A of the pulfe A H will be promoted, or made Wronger, having its pafiage already prepar’d as ’twere by the other parts preceding, and fo its imprellicn wil be fironger^And becaufe of its obliqui- tj to the Ray,there will be propagated a kind of faint motion into Q_Q^ the adjacent dark or quiet medium^ which faint motion will fpread fur- ther and further into Q_Q_ as the Ray is propagated further and further from A,naraely,as far as the line M A,whence all the triangle MAN will be ting’d with a Red. apd that Red will be the deeper the nearer it ap- proaches the line M A, and the p(der ox yelipvoer the nearer it is the line N A« And if the Ray be contipued,fo that the lines A N and B R (which are the bounds of the Remand Blue diluted) do meet and crols each other, there will be beyond that interfe^ion generated all kinds of Greeks.
Now.thefe being the proprieties of every fingle refrafted Ray of light, it will be eafie enough to Confider what mufc be the refult of very many luch Rays collateral : As if vve fuppofe infinite fuch Rays iuterjacent be- tween A R S B and A N O B, which arc the terminating : For in this cafe the Ray A R S B will have its Red txmngle intire, as lying next to the dark or quiet but the other fide of itRS will have no Blue^ becaufe the medium adjacent to it S B O, is mov’d or enlightned,and confequept- ly that light does deftroy the colour. So likewim will the Ray A N O B lofe its Red^hecauie the adjacent medium is mov’d or enlightned,but the other fide of the Ray that is adjacent to the dark, namely, A HO will prelerve its Blue entire, qnd thele Rays muft be fo far produc’d as till an apdBR cut each Other, before there will be any Green produc’d. From thefe Proprieties well confider’d,may be deduc’d the reafons of all the Fh^uamen^ of tfie prifme^ and of the Globules or drops of Water which conduce to the produftion of the Rainbow.
Next for the imprefiion they make on the Retina^ we will further ex- amine this Ftjipofhefi Suppofe therefore A B C D E F.ip the fifth Figure^ tp reprefept the Ball of the eye : on the Cornea of which ABC two Rays GACH andKCAI (which are the terminating Rays of a lumi- nous body) falling, are by the refraftion thereof colleded or convergd into two points at the bottom of the eye. NOw, becaufe thefe termi- nating Rays, and all the intermediate ones which come from any part of the Inminoits body^ are foppos’d by fome fufficient refraftion before they
• enter
M I C R O G R A P H I A.
enter the eye, to have their pulfes made oblique to their progreflion, and confequently each Ray to have potentially juferinducd two proprieties, or colourSjWZ.. a Red on the one fide, and a Blue on the other, which not- withftanding are never actually manifeft,butwhen this or that Ray has the one or the other fide of it bordering on a dark or unmov’d /ftediu^^there- fore as foon as thele Rays are entred into the eye.and lb have one fide of each of them bordering on a dark part of the humours of the eye, they will each of them aftually exhibit iome colour ^ therefore ADC the prO- duflion G A C H will exhibit a Blue^hecauCe the fide C D is adjacent to the dark mediumC Q_D C,but nothing of a 2fe^,becaule its fide A D is adjacent to the enlightned medium A D F A : And all the Rays that from the points of the luminous body are colledfed on the parts of the Retina between D and F fhall have their Blue fo much the more diluted by how much the far- ther thefe points of colleftion are diftant from D towards F 5 and the Ray AFC the production of K C A I, will exhibit a Red^ becaufe the fide A F is adjacent to the dark or quiet medium of the eye A P F A, but nothing of a ^/«e,becaufe its fide C F is adjacent to the enlightned medium C F D C, and all the Rays from the intermediate parts of the luminous body that are collected between F and D (hall have their Red to much the more di- luted, by how much the farther they are diftant from F towards D.
Now,becaufe by the refraCtion in the Cornea^and Ibme other parts of the eye, the fides of each Ray, which before were almoft parallel, are made to converge and meet in a point at the bottom of the eye, therefore that fide of the pulfi which preceded before thefe refraClions, (ball firft touch the Retina, and the other fide laft. And therefore according as this or that fide, or end of the pulle (hall be impeded, accordingly will the «»- prejjions on the Retina be varied 5 therefore by the Ray G A C H rc- fraCted by the Cornea to D there (hall be on that point a ftroke or imprel^ fion confus’d, whole weakeft end, namely, that by the line C D lhall pre- cede, and the ftronger, namely, that by the line A D lhall follow. And by the Ray K C A I refraCted to F, there lhall be on that part a confus’d ftroke or impreffion,whofe ftrongeft part,namely,that by the line C F ftial precede, and whole weakeft or impeded, namely, that by the line A F lhall follow, and all the intermediate points between F and D will re- ceive imprelfion from the convergd Rays lb much the more like the im- preflions on F and D by how much the nearer they approach that or this.
From the confideration of the proprieties of which imprelIions,we may colleCl: thele Ihort definitions of Colours ; That Blue is an imprejpon on the Retina of an oblique and confused pulje of light ^rohofe weakeji part pre- cedos^ and tohoje JirongeB follows. And, that Red is an imprejjton on the Re- tina of an oblique and confus'd pulfe of lights whofc JirongeJi part precedes ^and whoje weakpji follows.
Which proprieties, as they have been already manifefted,in the'Prilnie and falling drops of Rain, to be the caules of the colours there generated, may be eafily found to be the efficients alfo of the colours > appearing in thin laminated tranfparent bodicsj for the explication of which, all this has been preraifed* And
Micrograph! A.
And that this is a little clofer examioation of the Vh£nemmA and the Figure of the body, by this Hypothefis^ wiil make evident.
For firft (as we have already obferved) the laminated body muft be of a determinate thicknefs, that is, it muft not be thinner then luch a de- terminate quantity 5 for I have always oblerv'd, that neer the edges of thole which are exceeding thin, the colours difappear, and the part grows white 5 nor muft it be thicker then another determinate quantity 5 for I have likewile obferv’d, that beyond fuch a thicknefs,no colours ap- pear’d, but the Plate looked white, between which two determinate thicknefles were all the colour’d Rings 5 of which in forhe fubftances I have found ten or twelve, in others not half fo many, which I fuppofe de- pends much upon the tranfparency of the latninated body. Thus though the conlecutions are the fame in the Icumm or the Ikin on the top of me- tals 5 yet in thole confecutions the fame colour is not lb often repeated as in the confecutions iti thin Claft^ or in Sope-water, or any other more tranlparcnt and glutinous liquor 5 for in thele I haveoblerv’d, lova^ Green^ Blue^ Purple Red^ellowfireen^Blue^ Purple RedpCellowfireen^ Blue^ Purple 5 Red^ Tellovp^ See. to fucceed each other ,ten or twelve times, but in the other more opacous bodies the conlecutions will not be half fo many.
And therefore fecondly, the laminated body muft be tranlparent, and this I argue from this, that I have not been able to produce any colour at all with an opacous body,though never lb thin. And this I have often try’d, by prefling a Imall Globule of Mercury between two Imooth Plates of Glals, whereby I have reduc’d that body to a much greater thinnefs then was requifite to exhibit the colours with a tranfparent body.
Thirdly,there muft be a conliderable refleding body adjacent to the under or further fide of the lamina ox plate : for this I always found,that the greater that refledion was, the more vivid were the appearing colours.
From which Oblervations,it is moft evident, that the refledion from the under or further fide of the bodyis the principal caufe of the predudion of thefc colours 5 which,that it is lb,and how it conduces to that effed,! lhall further explain in the following Figure,which is here deferibed of a very great thicknels, as if it had been view’d through the Microfeope 5 and ’tis indeed much thicker than any MicroJccpe{l have yet us’d)has been able to fhew me thofe colour’d plates of Glals, or Mujcovie-glafs, which I have not without much trouble view’d with it 3 for though I have endeavoured to magnifie them as much as the Glafles were capable of, yet are they fo ex- ceeding thin, that I have not hitherto been able pofitively to determine their thicknels. This Figure therefore I here reprefent, is wholy Hy- pothetical.
Let ABCDHFE in the fixth Figure be a frujlum of Mufcovy-glafs^ thinner toward the end A E, and thicker towards D F. Let us firft fup- pofe the Ray agh b coming from the Sun, or fome remote luminous objed to fall obliquely on thie thinner plate B A E, part therefore is re- flededback,by eghd^ the firft whereby the perpendicular
L pulfe
(>6
Mi CROGR AP HIA.
pulfe H bis after refledion propagated by c c d^ equally remote from each other with ab^ a b^ fo that ag*gc^ oy b h ^ h d arc cither of them equal to a as is alfo c but the body B A E being tranlparentja part of the light of this Ray is refraded in the furface A B, and propa- gated hy gi k,h to the furface E F, whence it is refieded and refraded again by the furface A B. So that after two refradions and one refledion, there is propagated a kind of fainter Ray e m nf^ whole pulfe is not on- ly weaker by realbn of the two refradions in the furface A B, but by rea- fon of the time Ipent in paffing and repaliing between the two furfaces AB and EE, ef which is this fainter or weaker pulfe comes behind the pulfe cd‘-)io that hereby (the furfaces A Bj and E F being fb neer toge- ther, that the eye cannot difcriminate them from one) this confus’d or duplicated pulfe, whole ftrongeft part precedes, and whofe weakeft fol- lows, does produce on the Retina (or the optick^ nerve that covers the bottom of the eye) the fenfation of a
And fecondly, this Tellovo will appear fb much the deeper, by how much the further back towards the middle between cd andr^ thefpu- rious pulfe e/ is remov’d, as in 2 where the flirfacc BC being further remov’d from E F, the weaker pulfe ef will be nearer to the middle, and will make an impreffion on the eye of a Red.
But thirdly, if the two refleding furfaces be yet further remov’d afun- der'(as in 9 CD and EF are) then will the weaker pulfe be fb farr behind, that it will be more then half the diftancc between cd and cd. And in this cafe it will rather feem to precede the following ftronger pulfe, then to follow the preceding one, and confequently a Blue will be generated. And when the weaker pulfe is juft in the middle beween two ftrong ones, then is a deep and lovely Purple generated 5 but when the weaker pulfe ef is very neer to c J, then is there generated a Green^ which will be bluer ^ ox yellower^ according as the approximate weak pulfe docs precede or follow the ftronger.
Now fburthly, if the thicker Plate chance to be cleft into two thinner Plates, as CDFE is divided into two Plates by the furface GH then from the compofition arifing from the three refledions in the furfaces C D, G H, and EF, there will be generated feveral compounded or mixt colours, which will be very differing, according as the proportion be- tween the thickneftes of thofe two divided Plates C D H C, and G H F E are varied.
And fifthly, if thefe furfaces C D and F E are further remov’d afunder, the weaker pulfe will yet lagg behind much further, and not onely be coincident with the fecond, c d^ but lagg behind that alfb, and that fb much the more, by how much the thicker the Plate be , fb that by de- grees it will be coincident with the third c d backward alfb, and by de- grees, as the Plate grows thicker with a fourth, and fb onward to a fifth, fixth, feventh, or eighth 5 fb that if there be a thin tranfparent body, that from the greateft thinnefs requifite to produce colours, does, in the man- ner of a Wedge,by degrees grow to the greateft thicknefs that a Plate can be of,to exhibit a colour by the rcfle<ftion of Light from fuch a body, there
fhall
Micrograph i a.
iliall be generated leVeral conlecutions of colours^ whofe order ftoni the thin end towards the thick, (hall be Tell&w^Red^ rurple^^Ekefin&n 5 Telloti?^ Red^Purple^Blue^Green ^ TcUotc^Red^Purple^Bluefir^eH'^ Telloxc^c: and' thefe ib often repeated, as the weaker puhe does lofe pates with its Vrintary^ or firft pulftr, and is coincident with a lecond, third, fourth, fifth,ftxth;^c-, pulle behibd the firft. And this, as it is coincident^ i)t fbllovvs ftorti the firft I took of coloursjfo upon exeriment have I foofld it inmul-
titudes of inftances that ftem to prove it. One thing which feems of the greateft concern in this Hj/pothefo^ is to determine the greateft or leaft thicknefitequifitefortheleefrefts, which, though I have not been want- ing in attempting, yet fo exceeding thin are thefe coloured Plates, and lb imperfeeft our Microjcope.that I have not been hitherto luccelsfull^though if Illy endeavours (hall anfwer my expedations,! lhallhope to gratifie the curious Reader with feme things more remov’d beyond our reach hitherto.
Thus have I,with as much brevity as I was able, endeavoured to expli- cate (Hypothetically at leaft) the caules of the Phnenomena I formerly re- ' cited, on the confideration of which I have been the more particular.
Firft, becaufe I think thefe I have newly given are capable bf expli- cating all the Phdnomena of colours, not onely of tholc appearing in the Prijine, Water-drop, or Rainbow, and in laminated or plated bodies, but of all that are in the world, whether they be fluid or folid bodies^ whe- ther in thick or thin, whether tranfparent, or leemingly opacous, as I (hall in the next Obfervation further endeavour to Ihew. And fecondly, becaufe this being one of the tv/o ornaments of all bodies difeoverable by the fight, whether looked on with, or without a Merofeope^ it feem’d to defcrve (fomewhere in this Trad, which contains a defeription of the' Figure and Colour of feme minute bodies) to be (bmewhat the more in-^ dmatelj enquir'd into*
Obferv. X. (y Metalline, and other real Colours.
HAving inthe former Difcourfe, from the Fundamental caufe of Co- lour, made it probable, thdt there are but two Colours, and Ihewn^ that the Thantajm of Colour is caus’d by the fenfation of the oblique ot uneven pulfe of Light which is capable of no more varieties than two that arife from the two fides of the oblique pulfe, though each Of thofe be capable of infinite gradations or degrees (each of them beginning from White^ and ending the one in the deepeft Scarlet or Telloto^ the other in the deepeft Blue') I (hall in this SeHion fet down fome Obfervations which I have made of other colours, fuch as Metalline powders tinging or colour’d bodies and feveral kinds of tindures or ting’d liquors, all which, together with thofe I treated of in the former Obfervation will, I fuppofe, comprife the feveral lubjedls in which colour is obferv’d to be inherent, and the feveral manners by which it or is apparent
L 2 in
Micrograp hi a.
Jn them. And herd ihall endeavour to fhew by what compolition all kind of compound colours are made, and how there is no colour in the world but may be made from the various degrees of thefe two colours, together with the intermixtures of White.
And this being lb, as I (hall anon fliew, it feems an evident argument to me, that all colours whatfoever, whether in Huid or folid, whether in very tranfparent or feemingly opacous^ have the fame efficient caufe, to wit, fbme kind of refraBion whereby the Rays that proceed from fiich bodies, have their ipulkobliqmtedox confus’d in the manner I explicated in the former Se&ion , that is, a Red is caus’d by a duplicated or confus’d pulfe, whofe ftrongeft pulfe precedes,and a weaker follows : and a Blue is caus’d by a confus’d pulfe,where the weaker pulfe precedes^ and the ftronger follows. And according as thefe are, more or left, or varioufly mixtand compounded, fb arc the and confequently the phantafms of colours dwerpfied.
To proceed therefore ^ I fuppofe, that all tranfparent colour’d bodies, whether fluid or folid, do confift at leaft of two parts, or two kbds of fiibftances, the one of a fubftance of a fbmewhat differing refraction imm the other. That one of thefe fubftances which may be call’d the tinging fubftance, does confift of diftind parts, or particles of a determinate big- nefs which arc dijjeminated^ or difpers’d all over the other : That thefe particles, if the body be equally and uniformly colour’d, are evenly rang’d and difpers’d over the other contiguous body 5 That where the body is deepeft ting’d, there thefe particles are rang’d thickeft^ and where ’tis but faintly ting’d, they are rang’d much thinner, but uniformly* That by the mixture of another body that unites with either of thefe, which has a difiering refradion from either of the other, quite differing effeds will be produc’djthat is,the confecutions o£ the confus d pulfes will be much of another kind, and confequently produce other fenfations and phantafms of colours, and from a Red may turn to a Blue^ or from a Blue to SL Red, Sac,
Now, that this may be the better underftood, I fhall endeavour to ex- plain my meaning a little more fenfible by a Scheme : Suppofe we there- fore in the feventh Figure of the fixth Scheme, that A B C D reprefents a Veflel holding a ting’d liquor, let 1 1 1 1 1,&c. be the clear liquor, and let the tinging body that is mixt with it be E E, ck'c. F F, G G,
H H, d^c. whole particles (whether round, or fbme other determinate Figure is little to our purpofe)are firftof a determinate and equal bulk* Next, they are rang’d into the form of ^incunx, or Equilaterotriangu- lar order, which that probably they are fo,and whythey are fo,I fhall die* where endeavour to fhew.Thirdly,thcy are of fuch a nature,as doesdther more eafily or more difficultly tranfmit the Rays of light then the liquor 5 if more cafily,a Blue is generated, and if more difficultly, a or Scarlet.
And firft, let us fuppofe the tinging particles to be of a fubftance that does more impede the Rays of light , we fhall find that the pulfe or wave of light mov’d from AD to B C, will proceed on, through the con- taining medium by the pulfes or waves K K, L L, M M, N N, O O5 but
becaufe
MlCROGRAPHIAi
bccaufe fevcral of thde Rays that go to the conftitution of thefe pulfes be llvigged or ftojiped by the tinging particles EJF^GjH 5 therefore there (hall bte a ficmdary and weak pulfe that (hall follow the Ray, name- ly P P which will be the weaker: (irft, becauleit hashifFer d many re- fradions in the impeding body 5 next, for that the Rays will be a little difpersd or confus’d by reafon oftherefradion in each of the particles, whether rounder angular'^ And this will be more evidentj if we a little more clolely examine any one particular tinging Globule,
Suppofe wc therefore AB in the eighth Fgureoi the (mh Scheme^ to reprefent a tinging Globule or particle which has a greater refl ation than the liquor in which it is contain’d ; Let C D be a part of the pulfe of light which hproffagated throng the containing medium'-^ this puKe will be a little ftopt or impeded by the Globule^ and foby that time the puKe is paft to E F that part of it which has been impeded by palling through the Globule^ will get but to L IVl, and fo that puKe which has been gated through the Globule^ to wit, L M, N O, P Q_, will always come behind the pulfes E F, G H, 1 K,
• ■ Next, by reafon of the greater impediment in A B, and its Globular Fi- gure, the Rays that pals through it will be dKpers’d, and very much Icat^ ter’d. Whence C A. and D B which before went direB and parallel,w\\\ after the refraction in A B, diverge And Ipread by A P, and B fo that as the Rays do meet with more and more of thefe tinging particles in their way, by ip much the more will the puKe of light further lagg behind the clearer pulfe, or that which has fewer refraCtions, and thence the deeper will the colour be, and the fainter the light that is trajeCted through it 5 for not onely many Rays are reflected from the (urfaces of A B, but thole Rays that get through it are very much dilbrdered.
By this Hypohejis there is no one experiment of colour that I have yet met with, but may be, I conceive, very ratiohably folv'd, and perhaps, had I time to examine (evcral particulars requilite to the demonftration of it, I might prove it more than probable, for all the experiments about the changes and mixings of colours related in the Treatile of Colours, publilhed by the Incomparable Mr. Boyle ^ and multitudes of others which 1 haveObferv’d,do (b eafily and naturally flow from thofe principles,that I am very apt to think it probable, that they own their production to no other fecundary caufe : As to inftance in two or three experiments. In the twentieth Experiment, this liable AUthour has fhewn that the deep bluijh purple-colour of Violets^ may be turn’d into a Green^ by Alcali%ate Salts^ and to a Red by acid 5 that is, a Vurple conlifts of two colours, a deep Red^ and a deep Blue , when the Blue is diluted, or altered, or deftroy d by acid Saltsy:h.t Red becomes predominant, but when the Red is diluted by Alcali^te^ and the Blue heightned, there is generated a Green 5 for of a Red diluted, is made a TeUow^ and lelloiip and Blue make a Green.
NoWi becaufe the j^urious pulles Which caufe a Red and a Blue^ do the one follow the clear pulle, and the other precede it, it ulualiy follows, that thofe Saline refraCling bodies which do dilute the colour of the one, do deepen that of the other,; And this will be made manifefr by ah
mofr
Micrographia.
moft all kinds of Purples^ and many forts of Greens^ both thefe colours confiding ofmixt colours , for if we fuppofe A and A in the ninth Figure, to reprelent two pulfes of clear light, which follow each other at a con- venient diftance, A A, each of which hzs zfpurious pulfe preceding it, as B Bj which makes a Blue,and another following it, as C C, which makes a Red^ the one caus’d by tinging particles that have a greater refradion,the other by others that have a lels refrafting quality then the liquor or Jliefifiruum in which thefe are diflblv’d, whatfoever liquor does to alter the refradion of the one, without altering that of the other part of the ting’d liquor, muft needs very much alter the colour of the liquor 5 for iftherefraftionof the dijjbhent be increas’d, and the re&adion of the tinging particles not altered, then will the preceding Jpurhus pulfe be fliortned or ftopt, and not out-run the clear puUe fo much 5 fo that B B will become E E, and the Blue be diluted^ whereas the other Jpuriovs pulfe which follows will be made to lagg much more, and be further be* hind A A than before, and C C will become f f, and lb the TeUojv or Red will be heightned.
A Saline liquor therefore,mixt with another ting’d liquor, may alter the colour of it feveral ways, either by altering the reffadiion of the liquor in which the colour fwims ; or lecondly by varying the refraftion of the co- loured particles, by uniting more intimately either with Ibmc particular cerpufcles of the tinging body, or with all of them, according as it has a congruity to Ibme more elpecially, or to all alike : or thirdly, by uniting and interweaving it felf with fome other body that is already joyn’d with the tinging particles, with which fubftance it may have a congruity^ though it have very little with the particles themlelves : or fourthly, it may alter the colour of a ting’d liquor by dif joyning certain particles which were before united with the tinging particles, which though they were fomewhat congruous to thele particles, have yet a greater congruity with the newly infus’d Saline menjiruum. It may likewile alter the co- lour by further diflblving the tinging fubftance into linaller and fmaller particles j and lb diluting the colour , or by uniting feveral particles ther as in precipitations, and fb deepning it, and fomcfiich other ways, which many experiments and comparifbns of diftering trials together, might eafily inform one of
From thefe Principles applied , may be made out all the varieties of colours obfcrvable, either in liquors, or any other ting’d bodies, with great eale,and I hope intelligible enough, there being nothing in the«tf- tion of colour, or in the fuppos’d produdion,but is very conceivable, and may be poffible. >
The greateft difficulty that I find againft this Hypothejis^ is, that there fwm to be more diftinft colours then two, that is, then Yellow and Blue. This Objedion is grounded on this reafon, that there are feveral Reds, which diluted^ make not a Saffron or pale Yellow, and therefore Red, or Scarlet feems to be a third colour diftinft from a deep degree of Yellow.
To which I anfwer, that Saffron affords us a deep Scarlet tinfture,which may be diluted into as pale a Yellow as any, cither by making a weak fb-
lution
MlCROGRAPtHAi
lutioh of the Saffron, by infufing a fmall parcel of it into a great quantity of liquor, as in fpirit of Wine, or elfe by looking through a very thin quantity of the tindure, and which may be heightn’d into the lovelieft Scarlet,by looking through a very thick body of this tindure,or through a thinner parcel of it, Which is highly impregnated with the tinging body, by having had a greater quantity of the Saffron diffolv’d in a frtialler par- cel of the liquor.
Now, though there may be fbme particles of other tinging bodies that give a lovely Scarlet alfo, which though diluted never lb much with liquor, or looked on through never fo thin a parcel of ting’d liquor, will not yet afford a pale Yellow, but onely a kind of faint Red 5 yet this is no argu- ment but that thofe ting’dparticles may have in them the fainteft degree of Yellow, though we may be unable to make them exhibit it^F'or that power diluted depending upon the divilibility of the ting’d body, if i am unable to make the tinging particles fo thin as to exhibit that colour, it does not therefore follow,that the thing is impoffible to be done , now, the tinging particles of fbme bodies are of fitch a nature, that unlefs there be found fbme way of comminuting them into lels bulks then the liquor does diflolve them into, all the Rays that pafs through them mufl: necef larily receive a tindure fb deep, as their appropriate refradions and bulks compar’d with the proprieties of the diflblving liquor muff neceflarily difpofe them to cmprefs, which may perhaps be a pretty deep Yellow, or pale Red.
kuAt\i2.tt\{\s\s not gratis diBum^ I fhall add one inftance of this kind, wherein the thing is moft manifeft.
If you take Blue Smalt ^ you fhall find, that to afford the deepefi: Blue, which c£teris paribushas the greateft particles or fands^ and if you fur- ther divide, or grind thofe particles on a Grindftone, or porphyry done, you may by comminuting the fands of it, dilute the Blue into as pale a one as you pleafe, which you cannot do by laying the colour thin 5 for where- fbever any fingle particle is, it exhibits as deep a Blue as the whole mafo Now, there are other Blues, which though never fb much ground, will not be by grinding, becaufe confiding of very fmall particles, ve-
ry deeply ting’d,they cannot by grinding be adually feparated into fmal- Icr particles then the operation of the fire, or fbme other diflblving men- firuum^zh reduc’d them to already.
Thus all kind of Metalline colours, whether precipitated^ jublimld^ cat- cind^ or otherwife prepar’d, are hardly chang’d by grinding, as ultra, marine is not more dilut ed is Vermilion or Red-lead made of a more faint colour by grinding 3 for the fmalled particles of thefe which I have view’d with my greated Magnifying-Glafs, if they be well enlightned, ap- pear very deeply ting’d with their peculiar colours 3 nor, though I have magnified and enlightned the particles exceedingly, could I in many of them, perceive them to be tranfparent, or to be whole particles, but the fmalled fpecks.that I could find among well ground Vermilion and Red- lead^ feem’d to be a Red mafs, compounded of a multitude of lefs and left motes, which dickingtogether,compos’d a bulk, not onethoufand thou- fandth part of the fmalled vifible fand or mote. And
72
Micrographia.
And this I find generally in moll: Metalline colours, that though they confift of parts fo exceedingly iraall,yet are they very deeply ting’d,they being fo ponderous, and having fuch a multitude of terreftrial particles throng’d into a little room 5 fo that ’tis difficult to find any particle tranf- parent or refembling a prctious ftone, though not impoffible 5 for I have obferv’d divers fuch (hining and refplendent colours intermixt with the particles of Cinnaber^ both natural and artificial, before it hath been ground and broken or flaw’d into Vermilion : As I have allb in Orpiment^ Red-lead^ and Bife^ which makes me luppole, that thole metalline colours arc by grinding, not oncly broken and feparated aQually into fmaller pieces, but that they are alfo flaw’d and bruled ,whence they, for the moft partjbecome opacous^like flaw’d Cryltal or Glals,d^c. But for Smalts and verdituresj I have been able with a Microfcope to perceive their par- ticles very many of them tranfparent.
Now, that the others allb may be tranfparent, though they do notap- pear lb to the Microfcope ^m2iy be made probable by this Experiment : that if you take ammel that is almofl: opacous, and grind it very well on a Vorphyry^ or Serpentine^ the fmall particles will by reafon of their flaws, appear perfedily opacous 5 and that ’tis the flaws that produce this opa-' coujhef may be argued from this, that particles of the fame Ammel much thicker if unflaw’d will appear lomewhat tranfparent even to the eye 5 and from this alfo, that the moft tranfparent and clear Cryftal, if heated in the fire, and then luddenly quenched, lb that it be all over flaw’d, will appear opacous and white.
And that the particles o{ Metalline colours are tranlparent,may be argu- ed yet further from this, that the Cry ftals,or Vitriols of all Metals,are tranft parent, which fince they confift of metalline as well as filine particles, thole metalline ones muft be tranlparent, which is yet further confirm’d from this, that they have for the moft part, appropriate colours 5 lb the vitrioloi Gold is Yellow j of Copper,Blue,and foraetimes Green, of Iron, green 5 of Tinn and Lead, a pale White 5 of Silver,a pale Blue, C^c.
And next,the Solution of all Metals into menfruums are much the lame with the Vitriols^, or Cryftals. It feems therefore very probable, that thole colours which are made by the precipitation of thole particles out of the menfruums by tranlparent precipitating liquors Ihould be tranlpa^ rent allb. Thus Gold precipitates with oyl ofTartar^ or Jpirit ofVrine in- to a brown Yellow. Copper with fpirit of Vrine into a Mucous blue, which retains its tranlparency. A folution of fublimate (as the lame II- luftrious Authour I lately mention’d fhews in his 40. Experiment) precipi- tates with oyl of Tartar per deliquium^ into an Orange colour’d prech pitafe 5 nor is it lels probable, that the calcination of thole Vitriols by the fire,fhould have their particles tranfparent : Thus Saccarum Saturnij, 1 or the Vitriol of Lead by calcination becomes a deep Orange-colour’d miniumpNMich is a kind of precipitation by Ibme Salt which proceeds from , the fire , common Vitriol calcindy yields a deep Brown Red, d^c. '
A third Argument, that the particles of Metals are tranlparent, is, that i being calcin dy and melted with Glals, they tinge the Clals with tranfpa- rent '!
I
Ml GROG RA P Hi A» 7g
rent colours. Thus the Calx of Silver tinges the Glafs on which it is an- neal’d with a lovely YelloWjOr Gold colourjC^c.
And that the parts of Metals are tranfparent, may be farther argued from the tranfparency of Leaf-gold, which held againft the light, both to the naked eye, and the Microfiope^ exhibits a deep Green. And though I have never (een the other Metals laminated lb thin, that I was able to perceive them tranfparent, yet, for Copper and Brafs, if we had the fame conveniency for laminating them,as we nave for Gold,we might, perhapSjthrough fuch plates or leaves,find very differing degrees of Blue, or Green ^ for it Teems very probable, that thole Rays that rebound from them ting’d, with a deep Yellow, or pale Red, as from Copper, or with a pale Yellow,as from Brafs, have paft through them 5 for I cannot con- ceive how by refledion alone thofe Rays can receive a tindure, taking any Hypothejis extant.
So that we lee there may a fuflicient realbn be drawn from thele in- frances, why thole colours which we are unable to dilute to the paleft Yellow, or Blue, or Green, are not therefore to be concluded not to be i deeper degree of them 5 for llippoling we had a great company of Imall Globular elience Bottles,or roundGlafs bubbles.about the bignels of aWal*" nut, fill’d each of them with a very deep mixture of Saffiron, and that every one of them did appear of a deep Scarlet colour, and all of thenl together did exhibit at a diftanee, a deep dy’d Scarlet body. It does not follow, becaufe after we have come nearer to this congeries^or mals,and di^ vided it into its parts, and examining each of its parts feverally or apart, we find them to have much the lame colour with the whole mafs, it docs not, I fay, therefore follow, that if we could break thofe Globules fmaller, or any other ways come to fee a fmaller or thinner parcel of the ting’d liquor that fill’d thole bubbles, that that ting’d liquor muft always appear Red, or of a Scarlet hue, lince if Experiment be made,the quite contrary will enlue 5 for it is capable of being dilated into the paleft Yellow.
Now,that I might avoid all the Objeftions of this kind, by exhibiting an Experiment that might by ocular proof convince thole whom other realbns would not prevail with, I provided me a Prijmatkal Glaf^ made hollow, juft in the form of a Wedge, fuc^i as isreprefented in the tenth Figure of the fixth Scheme. The two parallelogram fides A B C D, A B E F, which met at a point, were made of the cleareft Looking-glafs plates well ground and polilh’d that I could get^thefe were joyn’d with hard ceiiient to the triangular fides, B C E, A D F, which were of Wood 5 the TaraUelo^ gram bale B C E F, likewife was of Wood joyn’d on to the reft with hard cement, and the whole Prijmatical Box was exadlly ftopt every where, but onely a little hole near the bafe was lcft,whcreby the Veflcl could be fill’d with any liquor, or emptied again at plcafure.
One of thefe Boxes (for I had two of them) I fill’d with a pretty deep tinftureof Aloes^ drawn onely with fair Water, and then ftopt the hole with a piece of Wax, then,by holding this Wedge againft the Light, and looking through it, it was obvious enough to fee the tinifturc of the liquor near the edge of the Wedge where it was but very thin, to be a pale but
M well
M I C R O G R A P H I A.
well colour’d Yellow, and further and further from the edge, as the li- quor grew thicker and thicker,this tindure appear’d deeper and deeper^^ K) that near the blunt end,which was leven Inches fromthe edge and three Inches and an half thick ^ it was of a deep and well colour’d Red. Now, the clearer and purer this tindure be, the more lovely will the deep Scarlet be, and the fouler the tindure be, the more dirty will the Red appear j fo that fome dirty tindures have afforded their deepeft Red much of the colour of burnt Oker or Spanip brown^others as lovely a co- lour as Vermilion^ and fome much brighter j but fevcral others, according as the tindures were worfe or more foul, exhibited various kinds of Reds, of very differing degrees.
The other of thefe Wedges, I fill’d with a moft lovely tindure of Cop- per, drawn from the filings of it,with fpirit of Vrine^ and this Wedge held as the former againft the Light, afforded all manner of Blues, from the fainteft to the deepeft,fo that I was in good hope by thele two,to have pro- duc’d all the varieties of colours imaginable 5 for I thought by this means to have been able by placing the two Parallelogram fides together, and the edges contrary ways,to have fo mov’d them to and fro one by another, as by looking through them in feveral places, and through feveralthick- neffos, I fbould have compounded, and confequently have feen all thole colours, which by other like compofitions of colours would have enfued.
But indeed of meeting with what I look’d for, I met with fomewhat more admirable 5 and that was, that I found my folf utterly unable to fee through them when placed both together, though they were tranlparent enough when afonder 5 and though I could fee through twice the thick- nels, when both of them were fill’d with the lame colour’d liquors, whe- ther both with the Yellow, or both with the Blue, yet when one was fill’d with the Yellow, the other with the BIue,and both looked through, they both appear’d dark, onely wh^n the parts near the tops were look’d through, they exhibited Greens, and thole of very great variety, as I exr pedi:ed,but the Purples and other colours,! could not by any means make, whether I endeavour’d to look through them both againft the Sun, or whether I plac’d them againft the hole of a darkned room.
But notwithftanding thismif-gheffing,! proceeded on with my trial in a dark room, and having two holes near pne another, I was able, by placing my Wedges againft them,to mix the ting’d Rays that paft through them, and fell on a Iheet of white Paper held at a convenient diftance from them as I pleas’d , fo that I could make the Paper appear of what fohmr J wouldjby varying the thicknefles of theWedges,and conlequent'^ ly the tincture of the Rays that paft through the two holes, and fome^ tiincs alfo by varying the Paper^ that is, in.fte<rf Pf a white Paper, holding a gray, or a black piece of Paper*
, Wh;?nce I experimentally found what I had Before imagin’d, that all the varieties of colours imaginable aye prod^p’d from feveral degrees of tliy^ rwo colours, namely, Yeljpw and, Bfoo, pr the mixture of them witl^'iight and da/khejs, that white and black, And all thofe alraoft infinite varieties which jLimnfrs and Paiot^s^ are able to ana^ke by com- pounding
MiCROGRAPHiA.
pounding thofe feveral colours they Jay on their Shels or Talads^ are no- thing elfej but Ibme made up offbme one or morej or all of
thefe four.
Now, whereas it may here again be cbje^tedjthat neither can the Reds be made out of the Yellows, added together, or laid on in greater or lels quantity, nor can the Yellows be made out of the Reds though laidne- ver fo thin 5 and as for the addition of White or Black, they do nothing but either whiten or darken the colours to which they are added,and not at all make them of any other kind of colour : as for inftance, Fcrmilion^ by being temper’d with White Lead, does not at all grow more Yellow, but onely there is mside a whiter kind of Red. Nor does Yellow Oker^ though laid never fo thick, produce the colour of nor though
it be temper’d with Black, does it at all make a Red; nay, though it be temper’d with White, it will not afford a fainter kind of Yellow, fuch as but onely a whiten’d Yellow ; nor will the Blues be diluted or deepned after the manner I fpeak of, zs Ik die 0 will never afford fb fine a Blue as Vltramarine or Bife ; nor will it, temper’d with Vermilion af ford a Green,though each of them be never fb much temper’d with white.
To which I anfwer,that there is a great difference between diluting a colour and whitening ofit ; for dtluting a colour, is to make the colour’d parts mor# thin, fo that the ting’d light, which is made by trajedling thofe ting’d bodies, does not receive fo deep a tinfture ; but whitening a colour is onely an intermixing of many clear refleftions of light among the fame ting’d parts ; deepning allb, and darkning or blacking a colour, are very different ; for deepning a colour, is to make the light pals through a greater quantity of the fame tinging body ; and darkning or blacking a colour, is onely interpofing a multitude of dark or black Ipots among the lame ting’d parts, or placing the colour in a more faint light.
Firft therefore,as to the former of thefe operations,that is,diluting and deepning, moft of the colours us’d by the Limners 'and Painters are in- capable of, to wit. Vermilion and Red-lead^ and Oker^ becaule the ting’d parts are lb exceeding fmall, that the mofi: curious Grindftones we have, are not able to feparate them into parts adually divided fo fmall as the ting’d particles are ; for looking on the moft curioully ground Ver- milion^ and Oker^ and Red-lead^ I could perceive that even thofe fmall corfufcles of the bodies they left were compounded of many pieces, that is, they leem’d to be fmall pieces compounded of a multitude of lefler ting’d parts ; each piece feeming almoft like a piece of Red Glals,or ting’d Cryflal all flaw’d ; fo that unlefs the Grindftone could actually divide them into Imaller pieces then thofe flaw’d particles were, which com- pounded that ting’d mote I could fee with my Microfeope^ it would be impoffible to dilute the colour by grinding, which, becaule the fineft we have will not reach to do in Vermilion or Okgr^ therefore they cannot at all, or very hardly be diluted.
Other colours indeed, whole ting’d particles are fuch as may be made fmaller, by grinding their colour, may be diluted. Thus Icveralofthe
M 2 Blues
Micrographia.
Blues may be diluted^z% S?^alt and Bije and MaJlicut^wKich. is YelloWjmay be made more faint ; And even Verwilion it felf may^by too much grind- ing, be brought to the colour of Red-lead^ which is but an Orange colour, which is confeft by all to be very much upon the Yellow. Now, though perhaps fomewhat of this diluting of Vermilion by overmuch grinding may be attributed to the Grindftone, or muller, for that fomc of their parts may be worn off and mixt with the colour, yet there fecms not ve- ry much, for I have done it on a Serpentine-ftone with a muller made of a Pebble, and yet obferv'd the fame effedl: follow.
And fecondly, as to the other of thefe operations on colours, that is, the deepning of them. Limners and Painters colours are for the moft part alfo uncapable. For they being for the moft part o^acous ^ and that opa~ coufncf^ as I faid before, proceeding from the particles, being very much flaw a. unleft we were able to joyn and re-unite thole flaw’d particles again into one piece, we (hall not be able to deepen the colour, which fince we are unable to do with moft of the colours which are by Painters accounted cpacous^ we are therefore unable to deepen them by adding more of the fame kind.
But becaufe all thole opacous colours have two kinds of beams or Rays reflefted from them,that is,Rays unting’d, which arc onely refledted from the outward liirface, without at all penetrating of the bodyjand ting’d Rays which are refledted from the inward lurfaces or flaws after they have luffer’d a two-fold refradtion 5 and becaulc that tranfparent liquors mixt with fuch corpufcles^ do,for the moft part, take off the former kind of refledlion 5 therefore thefe colours mixt with Water or Oyl, appear much deeper than when dry, for moft part of that white refledfion from the outward liirface is remov’d. Nay, fome of thefe colours are very much deepned by the mixture with fome tranfparent liquor, and that becaule they may perhaps get between thofe two flaws, and lb confcquently joyn two or more of thole flaw’d pieces together , but this happens but in a very few.
Now, tolhewthat all this is wotgratk di&um^ I (hall fet down fome Experiments which do manifeft thefo things to be probable and likely, which I have here deliver’d.
For, firft, if you take any ting’d liquor whatlbever, efpecially if it be pretty deeply ting’d, and by any means work it into a froth,the congeries of that froth (hall feem an opacous body, and appear of the fame colour, but much whiter than that of the liquor out of which it is made. For the abundance of refledtions of the Rays againft thole lurfaces of the bubbles of which the froth conlifts, does fo often rebound the Rays backwards, that little or no light can pals through^, and confequcntly the froth ap- pears opacous.
Again, if to any of thefo ting’d liquors that will endure the boiling there be added a fmall quantity of fine flower (the parts of which through the Microfeope are plainly enough to be perceiv’d to confift of tranfpa^ rent corpujcles') and luffer’d to boyl till it thicken the liquor, the mals of the liquor will appear opacous ting’d with the lame colour, but very much whiten’d. Thus
Micrographia.
Thus, if you take a piece of tranfparent Glafs that is well colour’d^ and by heating it, and then quenching it in Water, you flaw it all over, it will become opacoas, and will exhibit the fame colour with which the piece is ting d, but fainter and whiter.
Or, if you take a Pipe of ^this tranfparent Glafs, and in the flame of a Lamp melt it, and then blow it into very thin bubbles, then break thofe bubbles, and collect a good parcel of thofe hmin£ together in a Paper, you (hall find that a fmall thicknefs of thofe Plates will conftitute an opa- cous body,jand that you may fee through the mafs of Glafs before it be thm lammated^ above four times the thicknefs ; And befides, they will now afford a colour l^by refledion as other opacouf (as they are call’d) colours will, but much fainter and whiter than that of the Lump or Pipe out of which they were made.
Thus alfb,if you take rutty ^ and melt it with any tranfparent colour’d Glafs,it will make it become an op aeons colour’d lump, and to yield a pa- ler and whiter colour than the lump, by reflexion.
1 he fame thing may be done by a preparation of Antimony^ as has been (hewn by the Learned Phyfeiau, C. M. in his Excellent Obfervations and Notes on Nero’s Art of Glafs 5 and by this means all tranfparent co- lours become opacons, or ammls. And though by being ground they lofe very much of their colour, growing much whiter by reafbn of the multi- tude of fingle refledions from their outward furface, as I fhew’d afore, yet the fire that in the nealing or melting re-unites them, and fb re- news thofe Jpnrions refledions, removes alfo thofe whitenings of the co- lour that proceed from them.
As for the other colours which Painters ufe, which are tranfparent, and us’d to varnifh over all other paintintings, ’tis well enough known that the laying on of them thinner or thicker,does very much dilute or deepen 1' their colour.
Painters Colours therefore confifting moft of them of folid particles, lb (mail that they cannot be either re-united into thicker particles by any Art yet known,and confcquently cannot be deepned 3 or divided in- to particles fb fmall as the flaw’d particles that exhibit that colour, much Jefs into fmaller,and confcquently cannot be diluted-^ It is neceflary that they which are to imitate all kinds of colours, fhould have as many de- grees of each colour as can be procur’d.
And to this purpofe, both Limners and Painters have a very great va- - riety both of Yellows and Blues, befides feveral other colour'd bodies that exhibit very compounded colours, fuch as Greens and Purples 5 and others that are compounded of leveral degrees of Yellow, or feveral de- grees of Blue, fbmetimes unmixt, and fbmetimes compounded with Ic- veral other colour’d bodies.
The Yellows,*' from the paleft to the deepefl: Red or Scarlet, which has no intermixture of Blue , are pale and deep Majiicut^ Orpansent, Englif) Oker^ brown Ok§r^ Red Lead^ and Vermilion^ burnt Englif) ok^r^ and burnt brown ok^r^ which laft have a mixture of dark or dirty parts with them,
Their
Micrographia.
Their Blues arc feveral kinds of Smalts^ and Verditures^ and Bije^ and Vltramarine^ and Indico^ which laft has many dirty or dark parts inter- mixt with it.
Their compounded colour’d bodies, as Tink^^ and Verdigrefe^^NMich. are Greens, the one a Topingay^ the other a Sea-green 5 then which is a very lovely Purple.
To which may be added their Black and White, which they alfo ufually call Colours, of each of which they have feveral kinds, fiich as Bone Black^^ made of Ivory burnt in a clofe Veflel, and Blue Black^^ made of the fmall coal of Willow^ or fome other Wood 5 and Cullens earthy which is a kind of brown Black, &c. Their ufual Whites are either ar- tificial or natural White Lead^ the laft of which is the beft they yet have, and with the mixing and tempering thefe colours together, are they able to make an imitation of any colour Tvhatfoever : Their Reds or deep Yellows, they can dilute by mixing pale Yellows with them, and deepen their pale by mixing deeper with them 3 for it is not with Opacous co- lours as it is with tranfparent, whereby adding more Yellow to yellow, it is deepned, but in opacous diluted. They can whiten any colour by mix- ing White with it, and darken any colour by mixing Black, or fome dark and- dirty colour. And in a word, moft of the colours, or colour’d bodies they ufo in Limning and Painting, are foch, as though mixt with any other of their colours, they preforve their own hue, and by being in luch very final parts dilpers’d through the other colour’d bodies, they both, or altogether reprefent to the eye a compojitum of all 3 the eye be- ing unable, by reafon of their finalnefs, to diftinguilh the peculiarly co- lour’d particles, but receives them as one intire compojitum : whereas in many of thefe, the Microfeope very eafily diftinguifties each of the com- pounding colours diftindt, and exhibiting its own colour.
Thus have I by gently mixing Vermilion and Bife dry, produc’d a very finePurple,or mixt colour,but looking on it with the Microfeope could eafily diftinguifli both the Red and the Blue particles, which did not at all produce the Phantafm oiVm fic.
To fumm up all therefore in a word, I have not yet found any folid colour’d body,that I have yet examin’d,perfed:ly opacous 3 but thofe that are leaft tranfparent are Metalline and Mineral bodies, whofe particles ge- nerally, feeming either to be very fmall, or very much flaw’d, appear for the moft part opacous^ though there are very few of them that I have look’d on with a Microfope^ that have not very plainly or circumftanti- ally manifefted themfolves tranfparent.
And indeed, there foem to be fo few bodies in the world that are in minimis opacous, that I think one may make it a rational Huery^ Whether there be any body abfolutely thus opacous .<? For I doubt not at all (and I have taken notice of very many circumftances that make me of this mind) that could we very much improve the Microfope^ we might be able to fee all thofe bodies very plainly tranfparent, which we now are fain onely to ghefs at by circumftances. Nay , the Objed Glafles we yet make ufe of are fuch, that they make many tranfparent bodies to the
eye,
MiCROGRAPHiA,
eyejieem epacous through them, which if we widen the Aperture a little^ and caft more light on the objeds, and not charge the Glafles fo deep, will again dilclofe their tranfparency.
Now, as for all kinds of colours that are didblvable in Water,or other liquors, there is nothing ib manifeft, as that all thofe ting’d liquors are transparent and many of them are capable of being diluted and com- pounded or mixt with other colours, and divers of them are capable of being ver y much chang’d and heightned, and fixt with (everal kinds of Saline menjirmms. Others of them upon compounding, deftroy or vi- tiate each others colours, and precipitate^' ov otherwife very much alter each others tindure. in the true ordering and diluting^ and deepning, and mixing, and fixing of each of which, confifis one of the greateft iny- fteries of the Dyers ^ of which particulars, becaufe o\xv Microjeope ^&oras us very little information,! fiialladd nothing more at prelent , but onely that with a very few tindures order’d and mixt after certain ways, too long to be here fet down, I have been able to make an appearance of all the various colours imaginable, without at all ufing the help of Salts^ or Saline menjlruums to vary them-
As for the mutation of Colours by Saline me^JiruuntSy they have al- ready been lb fully and excellently handled by the lately mention’d In- comparable Authonr^xhdX I can add nothing,but that of a multitude of tri- als that I made, I have found them exadly to agree with his Rules and Theories, and though there may be infinite inftances, yet may they be reduc’d under a few Heads, and compris’d within a very few Rules. And generally I find, Salim menjiruums are moft operative upon thole colours that are Purple, or have fome degree of Purple in them, and up- on the other colours much leis. The fpurious pulfes that compofe which, being (as I formerly noted) fo very neer the middle between the true ones, that a Imall variation throws them both to one fide, or both to the other, and fo confequently raufi: make a vaft mutation in the formerly ap- pearing Colour.
Obferv. XI. Of Tigmxs obferv din [mail Sancf,
S And generally feems to be nothing elfe but exceeding Imall Pebbles^ or at Icaft Ibme very Imall parcels of a bigger ftone j the whiter kind feems through the to confift'of fmalltranfparent pieces of Ibme
pel/ucidhody^ each of them looking much like apiece of Alum^ or Sah Ge«?f,and this kind of Sand is anglea forsthe moft part irregularly ,without any certain fhape, and the of it are for the moft part flaw’d,though
amongft many of them it is not difficult to find fome that are perfectly pel/ucidj like a piece of clear Cry ftal, and divers likewife moft ciirioufly ibap’d, much after themanner of the bigger stiris of Cryftal, ot like the fmall Diamants I obfervd in certain Flints, of which I lhall by and by re- late, wfijeh laft particular feems to argue, that this kind of Sand is not
8o Micrograph! A.
made by the comminution of greater traniparent Cryftaline bodies, but by the concretion or coagulation of Water,or fbme other fluid body.
There are other kinds of courfer Sands, which are browner, and have their particles much bigger 5 thefe, view'd with a Microjcope^ leem much courfcrand more opacous fubftances,and moftofthem arc of lome irregu- larly rounded Figures , and though they fcem not lb opacous as to the naked eye, yet they feem very foul and cloudy, but neither do thcle want euriouUy tranfparent, no more than they do regularly figur'd and well colour’d particles, as I have often found.
There are multitudes of other kinds of Sands, which in many particu- lars, plainly enough dilcoverable by the Mcrofeope^differ both from thcle laft mention’d kinds of Sands, and from one another : there leeming to be as great variety of Sands,as there is of Stones. And ’as amongft Stones Ibme arc call’d precious from their excellency, lb alfo are there Sands which dclerve the lame Epithite for their beauty 3 for viewing a fmall parcel of Eajl-India Sand (which was given me by my highly honoured friend, Mr. Daniel ColwaU') and, fince that, another parcel, much of the lame kind, I found leveral of them, both very tranfparent like precious Stones, and regularly figur’d like Cryftal, Cornijb Diaraants, fome Rubies, d^c. and alio ting’d with very lively and deep colours, like Rnbys, Saphyrs^ Eme- ralds^ &c. Thefe kinds of granuls I have often found allb in Engli^ Sand* And ’tis cafie to make fuch a counterfeit Sand with deeply ting’d Glals, Enamels and Painters colours.
It were endlcls to deferibe the multitudes of Figures I have met with in thefe kind of minute bodies, luch as SphericalyOvalJ^yramidal^ Conical^ Trifmatical^ of each of which kinds I have taken notice.
But amongft many others, I met with none more obfcrvable than this pretty Shell (deferibed in the Figure X. of the fifth Scheme) which, though as it was light on by chance, deferv’d to have been omitted (I being unable to diredf any one to find the like) yet for its rarity was it not inconfiderable, elpecially upon the account of the information it may afibrd us. For by it we have a very good inftance of the curiofity of Na- ture in another kind of Animals which are remov’d, by rcalbn of their minutenels,beyond the reach of our eyes, lb that as there are feveral forts of Infers, as Mites, and others,fo Imall as not yet to have had any names 3 (fome of which I Ihall afterwards deferibe) and fmall Fifties, as Leeches in Vineger 3 and final vegetables, as Mofi, and Rofc-Leave-plants 5 and Imall Mulhroms, as mould: foare there, it feems, Imall Shel-fifti like- wife, Nature fliewing her curiofity in every Tribe of Animals^ Vege- tables^ and Minerals,
I was trying feveral Imall and fingle Magnifying Clafles, and calually viewing a parcel of white Sand, when I perceiv’d one of the grains exadcly Ihap’d and wreath’d like a Shell, but endeavouring to diftinguilh it with my naked cyc,it was lb very finall,that I was fain again to mate ufe of the Glals to find it 3 then,whileft 1 thus look’d on it, with a Pin I feparated all the reft of the granules of Sand,and found it afterwards to appear to the naked eye an exceeding %all white (pot, no bigger than the point of a
Pin.
X.
Vl I C R O G K A P H I
Pin. Afterwards I view'd it every way with a better Mkrofcope^Sind fonnd itonboth fidesjandedge-^ways, to refemble the Shell of a fmall Water Snail with a flat fpiral J^iell : it had twelve wreathmgs, &ci
all very proportionably growing one lefs than another toward the middle Or center of the Shell, where there was a very fmall round white fpot. I could not certainly difeoVer Whether the Shell were hollow or rtot, but it feem’d fill’d with fomewhat, and tis probable that) it might be pettiffd2LS other larger Shels often are, fuebas are metifiqri dinthe
{tVQUt^QtithObJervatioiJ.
Obferv. XII. Of Gravel inVrine.
I Have often obferV'd the Sand Ot idravel of Utinej tii'hich leeats to be a tartareouf fubftance, generated out of a Saline and a terrejirial fiib- Ifance cryflalli^d together, in the form of Tartar^ fometimes {ticking to the fides of the Vrinal^ but for the moft part finking to the bottom, and there lying in the form of coorfe common Sand 5 thefe, through the Afi- crofcope^apipezrto be a Company of fmall bodies,partly tranfparent, and partly opacous^ fome White, fome Yellow, ibme Red, others of more brown and duikie colours.
The Figure of them is for the moft part flat, in the manner of Slats, or fuch like plated Stones, that is, each of them feemto be made up of feve- ral other thinner Plates, much like AInfeovie Glamor Englijh Sparrow the Ja{f of which, the white plated Gravel feems moft likely f for they feem notonely plated like that, but their fides fhap’d ahb into Rhombs^Rhom- boeids^znd. fometimes into ReB angles and /quarcs.^Thtn bigneft and Figure may be fecn in the fccond Figure of the fixth which reprefents about a dozen of them lying upon a plate ABC D,fonie of which, as c, d, feem’d more regular than the reft, and e, which was a fmall one, ftick- ing on the top of another, was a perfed Rhombdeid on the top, and had four ReB angular fides.
The line E which was the tnealure of the Merofeope^ is pi part of an Englijh Inch, fo that the greateft bredth of any of them, exceeded not I as part of an Inch.
Putting theie into feveral liquors, I found Oj/l of ViirioJ Spitit of Zlrine^atid fevctal other Saline ntenjiruums to diflolve them; and the firft of thefe in lefs than a minute without £^;///ztzV>»,Water,and feveral other liquors, had no hidden operation upon them. This I mention, becaule thofe liquors that diflblve them,firft make them very white, not vitiating^ but rather reftifying their Figure, and thereby make them afford a very pretty objeeft for the Microfeope,
How great an advantage it would be to fuch as are troubled with the Stone, to find fome fnenjtruum that might diflblve them without hurting the Bladdcr^is eafily imagin’d, fince fome injeBions made of fuch bodies might likewife diflolve the ftone, which feems much of the fame nature.
N P
82
Micrographia.
It may therefore, perhaps, be worthy fomePhyficians enquiry, whether there may not be Ibmething mixt with the Urine in which the Gravel or Stone lies, which may again make it diflblve it, the firft of which feems by it’s regular Figures to have been fometimes Crjfial/izd out of it. For whether this Cryjlallization be made in the manner as Alum^ Peter^Scc. are cr)flalliz,ed out of a cooling liquor, in which, by boyling they have been diflblv’d 5 or whether it be made in the manner of Tart arum Vitriolatum^ that is, by the Coalition of an acid and a Sulphureous lubftance, it foems not impoffible,but that the liquor it lies in,may be again made a dijfolvenf of it. But leaving thefe inquiries to Phyhcians or Chymifts, to whom it does more properly belong, I lhall proceed.
Oblcrv. X I H. Of the fmall Diamants, or Sparks in Flints.
CHancing to break a Flint ftone in pieces, I found within it a certain cavity all crufted over with a very pretty candied fubftance, Ibme of the parts of which, upon changing the pofture of the Stone, in refpedi: of the Incident light, exhibited a number of Imall, but very vivid re^ fledions , and having made ule of my Microjeope^ I could perceive the whole liirface of that cavity to be all befet with a multitude of little Cryjialine or Adamantine bodies, fo curioufly fliap’d, that it afforded a not unpleafing objed.
Having confidered thofe vivid repercujjions of light,I found them to be made partly from the plain external furface of thefe regularly figured bodies (which afforded the vivid reflexions) and partly to be made from within the Ibmewhat pellucid body, that is, from fome furface of the body,oppofite to that fuperficies of it which was next the eye.
And becaufe thefe bodies were fo fmall, that I could not well come to make Experiments and Examinations of them, I provided me feveral fmall firice of Cryftals or Diamants, found in great quantities in Corn- walLznd are therefore commonly called Cornijh Diamants : thefe being very pellucid^ and growing in a hollow cavity of a Rock (as I have been feveral times informed by thofe that have obferv’d them) much after the fame manner as thefe do in the Flint ^ and having befides their outward furface very regularly fhap’d, retaining very near the fame Figures with fome of thofe I obferv’d in the other, became a convenient help to me for the Examination of the proprieties of thofe kinds of bodies.
And firft for the RefleXions , in thefe I found it very obfervable. That the brighteft refieXions of light proceeded from within the pellucidhody 5 that is, that the Rays admitted through the pellucid fubftance in their getting out on the oppofite fide, werV by the contiguous and ftrong re- neXing furface of the Air very vividly refieXed, fo that more Rays were refieXed to the eye by this furface, though the Ray in entring and getting out of the Cryftal had fuffer’d a double refraXion, than there were from the outward furface of the Glafs where the Ray had fufter’d no reflraXion at all. And
Sche.\~n
MiC RO GR A PHI A.
And that this was the furface of the Air that gave fo Vivid a re-percuf- fion I try’d by this means. I funk half o^ajiiria in Waterj fo that only Water was contiguous to the under iurfacCj and then the internal re-' fledbion was lb exceedingly faint, that it was fcarce difcernable. Again,
I try’d to alter this vivid reflection by keeping off the Air, with a body not fluid, and that was by rubbing and holding my finder very hard againfl: the under furface, fo as in many places the pulp of my finger did touch the Glafs, without any interjaceKt air between 5 then bbferving the refledbion, I found,that wherefbever my finger or Ikin toucht the furface, from that part there was no refledbion, but in the little furrow's or creafes of my fkin, where there remain’d little fmall lines of air,from them was. return’d a very vivid refledtion as before. I try'd further,by making the furface of very pure Quickfilver to be contiguous to the under furface of this pellucid body, and then the refledbion from that was fo exceeding- ly more vivid than from the air , as the refledbion from air was than the refledbion from the Watery from all which trials I plainly faw, that the ftrong refle(fi:ing air wasthe caufe of this rh£r2omenon.
And this agrees very well with the Hypethejis of light and Vellucidho^ dies which I have mention’d in the defcription of Mufcovy-glaf'^ for we there fuppofe Glafs to be a medium ^'w\f\ch. does lefs refifb the pulfe oflight, and confequcntly,that mofb of the Rays incident on it enter into it,ahd at e refradbed towards the perpendicular 5 whereas the air I fuppofe to be a: body that does more refifb it, and confequently more are re-percufs' d then do enter it : the fame kind of trials have I made, with Cryjialline Glaf^ with drops of fluid bodies, and feveral other ways,which do all feem to I agree very exadbly with this Theory. So that from this Principle well efta- blifh’d, we may deduce feverall Corollaries not unworthy obfervation.
; And the firfb is, that it plainly appears by this, that the produdbion of the Rainbow is as much to be afcribed to the refledbion of the concave furface of the air, as to the refradbion of the Globular drops : this will be evidently manifefb by thefe Experiments, if you foliate that part of a Glafs-ball that is to refledb an /m, as in the Cartejian Experiment, above mention’d, the refledbions will be abundantly more fbrong, and the co- lours more vivid : and if that part of the furface be touch’d with Water, fcarce affords any fenfible colour at all.
Next we learn, that the great reafbn why pellucid bodies beaten fmall are white, is from the multitude of refledions, not from the particles of the body, but from the contiguous furface of the air. And this is evident- ly manifefbed, by filling the Interjlitia of thofe powder’d bodies with Water, whereby their whitenefs prefently difappears. From the fame f reafbn proceeds the whitenefs of many kinds of Sands, which in the I crojcope appear to be made up of a multitude of little/?e/5feaV/ bodies,
^ whole brightefb refledbions may by the Microjcope be plainly perceiv’d i\ to come from their internal lurfaces 5 and much of the whitenefs of it may 1 be defbroy’d by the afiufion of fair Water to be contiguous to thofe I fiirfaces.
I The whitenefs alfb of froth, is for the mofb part to be afcribed to the
N 2 refledbion
$4 Micrographia.
refleftion of the light from the furface of the air within the BubbleSjand very little to the refleftion from the llirface of the Water it felf : for this laft refledion does not return a quarter fo many Rays, as that which is made from the furface of the air,as I have certainly found by a multitude of Obfervations and Experiments.
The whitenels of Linnen^ Taper ^ 8cc. proceeds much from the
fame reafon, as the Mkrofeope will eafily difeover , for the Paper is made up of an abundance of pellucid bodies, which afford a very plentifull re- fledion from within, that is, from the concave furface of the air contigu- ous to its component particles 5 wherefore by the affufion of Water, Oyl, Tallow,Turpentine,<^c."all thofe refledions are made more faint^and the beams of light are fuffer’d to tra jed & run through the Paper more freely.
Hence further we may learn the reafon of the whitenefs of many bo- dies, and by what means they may be in part pellucid: As white Marble for inftance, for this body is compofed of a pellucid body ex- ceedingly flaw’d, that is, there are abundance of thin, and very fine cracks or chinks amongft the multitude of particles of the body,that con- tain in them fmall parcels of air, which do fo re-percufaud drive back the penetrating beams, that they cannot enter very deep within that body, which the Mkrofeope does plainly inform us to be made up of a Congeriei of pellucid particles. And I fvirther found it fomewhat more evidently by fome attempts I made towards the making tranlparcnt Marble, for by heating the Stone a little, and foaking it in Oyl, Turpentine, Oyl of Tur- pentine,I found that I was able to fee much deeper into the body of Marble then before 5 and one trial, which was not with an undluous lub- ftance,fucceeded better than the reft, of which, when I have a better op- portunity, I (hall make further trial. *
This alfo gives us a probable reafon of the fo much admired Ph£no- mena of the Oculus Mundi^ an Oval ftone, which commonly looks like white Alabafter, but being laid a certain time in Water, it grows pellucid^ and tranfparent, and being fiifier’d to lie again dry, it by degrees lofos that tranfparency, and becomes white as before. For the Stone being of a hollow Ipongie nature, has in the firft and laft of thefe appearances, all thofe pores fill’d with the obtunding and reflefting air 5 whereas in the fecond, all thofe pores are fill’d with a medium that has much the fame refraction with the particles of the Stone, and therefore thofe two being contiguous^ make,as’twere, one continued medium^ of which more is laid in the 1 5. Ohfervation.
There are a multitude of other Vhanomenajihzt are produc’d from this fame Principle,|which as it has not been taken notice of by any yet that I know, fo I think, upon more diligent obfervation, will it not be found the leaft confiderable. But I have here onely time to hint Hypothefes^ and not to prolecute them fo fully as I could wifti 5 many of them having a vaft extent in the production of a multitude of Vhanomena^ which have been by others,either not attempted to be explain’d, or elfe attributed to fome other caufe than what I have afiign’d, and perhaps than the right 5 and therefore I lhall leave this to the profecution of fuch as have more leifure :
onely
Micrographia.
onely before I leave it, I muft not pretermit to hint, that by this Prin- ciple, multitudes of the of the air, as about Clouds^ Me-
teors^ Hakes^Scc, are mold plainly and (perhaps) truly explicable, multi- tudes alfo of the Fh<enomena in colour'd bodies, as liquors, arc de-
ducible from it.
And from this I fhall proceed to a fecond confiderable Vh£tiotnenon which thefe Diamants exhibit, and that is the regularity of their Figure^ which is a propriety not lefs general than the former 5 It comprifing with- in its extent, all kinds of Metals^ all kinds of Minerals ^mott Precious fiones^ all kinds.’of .5*<2///,muItitudes of Earths^znd almoft all kinds of fluid bodies. And this is another propiety, which, though a little fuperficially taken notice'of by fome, has not, that I know, been lb much as attempted to be explicated by any.
This propriety ofbodies,asI think it the mod worthy, and next in or- der to be confider'd after the contemplation of the Globular Figure^ fb have I long had a defire as wel as a determination to have profecuted it if I had had an opportunity , having long fince propos’d to my felf the method of my enquiry therein, it containing all the allurements that I think any enquiry is capable of: For,firfl: I take it to proceed from the moft fimple principle that any kind of form can come from, next the Globular^ which was therefore the firft I let upon, and what I have therein perform’d, I leave the Judicious Reader to determine. For as that form proceeded from a propiety of fluid bodies, which I have call’d Congruity^ or Incon- gruity'^ fo I think, had I time and opportunity, I could make probable, that all thefe regular Figures that are fo confpicuoufly various and curi- . <?»/,and do fo adorn and beautifiefuch multitudes of bodies, as I have above hinted,arifc onely from three or four feveral pofitions or poftures of Globular particles,and thofe the mofi: plain,obvious, and necellfry con- junftions of frich figur’d particles that are pollible, fo that fuppofing luch and luch plain and obvious caules concurring the coagulating particles mull neceflarily compole a body of liich a determinate regular Figure, and no other 5 and this with as much neceffity and obvioulhels as a fluid body encompall with a Heterogeneous fluid mull be protruded into a Spherule or Globe. And this I have ad oculum demonllated with a com- pany of bullets,and fome few other very fimple bodies 5 fo that there was not any regular Figurc,which I have hitherto met withall, of any of thole bodies that I have above named, that I could not with the eompofition of bullets or globules, and one or two other bodies, imitate, even almoll by Ihaking them together. And thus for inllance may we find that the Globular bullets will of theralelves,if put on an inclining plain jjb that they may^tun together, naturally run into a triangular order, compofingall the variety of figures that can be imagin’d to be made out of equilateral triangles 5 and luch will you find,upon trial,all the furfaces of Alum toHbe compos’d of; For three bullets lying on a plain, as dofe to one another as they can compole an equilatero-triangular form, as in A in the -/.Scheme. If a fourth be joyn’d to them on either fide as clofely as it can, they four compofe the moll regular Rhombus confilling of two (squilaPeral triangles^
as
MiCROGRAP HIA.
as B. If a fifth be joyn’d to them on either fide in asclofe a pofition a§it can, which is the propriety of the Textnre^it makes a Trapezium^ or four- fided Figure, two of whofc angles are 1 20. and two 60. degrees, as C, If a fixth be added, as before, either it makes zn<equilateral triangU^as D, or a Rhomboeid, as E,or an Hex-atignlar Figure^ as F, which is com- pos’d of two priniarj! Rhombes. If a feventh be added, it makes either ^n squilatero-hexagonal Figure , as G , or fome kind of fix-fided Fi^ gure^ as H, or I. And though there be never fo many placed together, they may be rang’d into fome of thefc lately mentioned Figures, all the angles of which will be either do. degrees, or 120. as the figure K. which \s an (equiangular hexagonal Yignxe is compounded of 12. Globules^ or may be of 2 5, or 27, or 96, or 42, &c. and by thefe kinds of texture, or pofition of globular bodies, may you find out all the variety of regular ftiapes, into which the fmooth furfaces of Alum are form’d, as upon ex- amination any one may eafily find 5 nor does it hold only in fuperficies,but in folidity alfo.for it’s obvious that a fourth Globule laid upon the third in this texture, compofes a regular Tetrahedron^ Vhich is a very ufiial Figure of the Crjftals oi Alum. And (to haften) there is no one Figure into which Alum is obferv d to be cryftallized, but may by this texture of Globules be imitated, and by no other.
I could inftance alfo in the Figure of Sea-falt^anA Sal-gem it is com- pos’d of a texture of Globules, placed in a cubical form, as L, and that all the Figures ofthofe Salts may be imitated by this texture of Globules,and by no other whatfbever. And that the forms Vitriol and oi Salt-Pet er,
as alfo of Cryfial,Hore-fro^, 8cc. are compounded of thele two textures, but modulated by certain proprieties : But I have not here time to in- fift upon, as I have not neither to ihcw by what means Globules come to be thus context, and what thofe Globules are, and many other particulars requifite to a full and intelligible explication of this propriety of bodies. Nor have I hitherto found indeed an opportunity of profocuting the in- quiry fofarr as I defign’d 5 nor do I know when I may, it requiring abun- dance of time, and a great deal of afliftance to go through with what I defign’d 5 the model of which was this :
Firft,to get as exadf and full a collcdfion as I could, of all the difiering kinds of Geometrical figur’d bodies, fome three or four foveral bodies of each kind.
Secondly, with them to get as exaft a Hiftory as pofiibly I could learn of their places of Generation or finding, and to enquire after as many circumftances that tended to the Illuftrating of this Enquiry, as poflibly I could obferve.
Thirdly, to make as many trials as upon experience I could find re- quifite,in Difilblutions and Coagulations of foveral cryftallizing Salts ^ffbr the necdfull inftrudeion and information in this Enquiry.
Fourthly, to make foveral trials on divers other bodies, as Metals, Minerals, and Stones, by diflblving them in foveral Menjiruums, and cryftalizing them, to fee what Figures would arifo from thofe foveral Compojitums,
Fifthly,
M I C R O G R A P H i A.
Fitfthlyj to make Cora pofitions and Coagulations of feveral Salts to^ gether into the iame mals, to obfcrve of what Figure the produd of them would be j and in all, to note as many circumftances as I fhould judge conducive to my Enquiry.
Sixthly, to enquire the clofene(s,or rarity of the texture.of thefe bo- dies, by eXaiuining their gravity, and theif refradioil,
Seventhly, to enquire particularly what operations the fire has upon leveral kinds of Salts, what changes it caufes in their Figures, Textures, or Energies.
Eighthly, to examine their manner of diflolution, or ading upon thole bodies dilloluble in them ^ The texture of thofe bodies before and after the procels. And this for the Hiftory.
Next for the Solution, To have examin’d by Vv^hat, and how many means, luch and fuch Figures, adions and effeds could be produc'd poliibly.
And laltly, from all circumftances well weigh’d, I Ihould have ertdea^ vourcd to have Ihewn which of them was moft likely, and (if the infor- mations by thele Enquiries would have born it) to have demonftrated which of them it muft be, and was.
But to proceed, As I believe it next to the Globular the moft limple ^ fo do I, in the fecond place, judge it not lefs plcafant 5 for that which makes an Enquiry pleafant, are, firft a noble Inventnm that promiles to crown the fuccelsfull endeavour 5 and fuch muft certainly the knowledge of the elEcient and concurrent caufes of all thefe curious Geometrical Figures be, which has made the Philofophers hitherto to conclude nature in thele things to play the Geometrician, according to that faying of fUto^ ‘o 0ii< Or next, a great variety of matter in theEnqui^
ry 5 and here we meet with nothing left than the Mathematicks of nature^ having every day a new Figure to contemplate, or a variation of the fame in another body.
Which do afford us a third thing, which will yet more fweeten the En- quiry ,and that is,a multitude of information 5 we are not fo much to grope in the dark, as in moft other Enquiries, where the Inventnm is great 5 for having luch a multitude of inftances to compare, and fuch ealiewaysof generating,or compounding and' of deftroyiqg the form, as in xS\Q. 'Solution and Cryfiallizaiioh of Salts, we cannot but learn plehtifull information to proceed by. And this will further appear fromtheuniverfalityofthe Principle which Nature has made ufe of almoft in all inanimate bodies. And therefore, as the contemplation of them all conduces to the know- ledg of any one ^ lb from a Scientihcal knowledge of any one does follow the fame of all, and every one.
And fourthly, for the ufefulncft of this knowledge, when acquir’d^ certainly none can doubt, that conliders that it caries us a ftep for- ward into the Labirinth of Nature, in the right way towards the end we propofe our felves in all Philolophical Enquiries. So that know-* ing what is the form of Inanimate or Mineral bodies. We lhall be the better able to proceed in our next Enquiry after the forms of Vegeta^
tive
88
Mi CROGR AP HIA.
tive bodies , and laft of all, of Animate ones, that feeming to be the higheft ftep of natural knowledge that the mind of man is capable of
Obferv. XIV. Of feveral kinJes of frozen Figures,
I Have very often in a Morning, when there has been a great hoar-frojl^ with an indifferently magnifying Mcrofiope^ obferv’d the fmall Stirie^ or Gryftalline beard, which then uflially covers the face of moft bodies that lie open to the cold air, and found them to be generally Hexangular prifffiatical bodies, much like the long Cryftals of Salt-peter^ fave onely that the ends of them were differing : for whereas thofe of Nitre are for the moft part pyramidal^ being terminated either in a point or edge 5 -thefeof Froft were hollow, and the cavity in fome feem'd pretty deep, and this cavity was the more plainly to be feen, becaufe ufually one or other of the fix parallelogram fides was wanting, or at leafi: much fhorter then the reft.
But this was onely the Figure of the Bearded hoar-froji 3 and as for the particles of other kinds of hoar-frojis^ they feem’d for the moft part irre- gular, or of no certain iFigure. Nay, the parts of thofe curious branch- ings, or vortices^ that ufually in cold weather tarnifh the furface of Glafs, appear through the Microjeope very rude and unftiapen, as do moft other kinds of frozen Figures^ which to the naked eye feem exceed- ing neat and curious, fuch as the Figures of S»on>, frozen Vrine^ Hail^ feveral Figures frozen in common Water,c^c. Some Obfervations of each of which I fhall hereunto annex, becaufe if well confider’d and ex- ami nd, they may, perhaps, prove very inftrudlive for the finding out of what I have endeavoured in the preceding Obfervation to fhew, to be (next the Globular Figure which is caus'd by congruity^ as I hope I have made probable in the {v^^Obfervation) the moft fimple and plain opera- tion of Nature, of which, notwithftanding we are yet ignorant.
I.
Several Ohfervables in the fix-branched Figures form'd on the fur- face of Vrine by freezing,
Sihern. 8. 1 The Figures were all frozen almoft even with the fiirfacc of the
Fig. ». Vrifte inthe Veflel, but the bigger ftems were a little prominent above that forface, and the parts of thole ftems which were neareft the center (a) were biggeft above the forface.
2 I have obferv’d leveral kinds of thefo Figures, fome Imaller, no big- ger then a Two-pence, others lb bigg, that I have by meafure found one of its ftems or branches above four foot long 3 and of thefe, fome were pretty round, having all their branches pretty neer alike 3 other of them were more extended towards on«fide, asufoally thofe very laygeones
were
T
/
f
M I c R d G R A P H I Ai
werCj which I have obrerv’d in Ditches which have been fidl of foul water.
g None of all thefe Figures I have yet taken notice of, had any regu- lar pofition in refpeft of one another, or of the hdes of the Veflel5 nor did I find any of them equally to exaftnefs extended every way from the center a.
4 Where ever there was a center, the branchings from it, ab^4c^cid^ a e, ag, were never fewer, or more then fix, which ufually eoncurf d, or met one another very neer in the fame point or center, /15 though oftentimes not exafdy ^ and were enclin’d to each other by an angle, of very necr fixty degrees, I fay, very neer, becaule, though having en- deavoured to meafure them the moft acurately I was able, with the largefi: Compafies I had, I could not find any fenfible variation from that meafure, yet the whole fix-branched Figure Teeming to compole a folid angle, they muft necefiarily be fomewhat lefs.
5 The middle lines or ftems of thefe branches, a a e, a 4 af^ ag^ feem’d fomewhat whiter, and a little higher then any of , the intermediaH branchings of thefo Figures ? and the center was the mofi: prominent part of the whole Figure, foeming the apex of a folid angle or pyramid^ each of the fix plains beinga little enclin’d below the ftirface of the Vnn,
6 The lateral branchings ifiiiing out of the great ones, fijeh as op^ See. were each of them inclin’d to the great ones, by the fame angle
of about fixty degrees,as the great ones were one to another, and always the bigger branchings were prominent above the lefi, and the left above the leaft, by ^roipoitiomte gradations.
7 The lateral branches fhooting out of the great ones, went all of them from the center, and each of them was parallel to that great branch, next to which it lay fo that as all the branches on one fide were parallel to one another, fo were they all of them to the approximate great branch, asp Oy q r, as they were parallel to each other, and (hot from the center, fo were they parallel alfo to the great branch a b.
8 Some of the Items of the fix branches proceeded ftraight, and of a thicknels that gradually grew fharper towards the end, as ag.
9 Others of the Items of thofe branches grew bigger and knotty to- wards the middle, and the branches alfo as well as ftems, from Cylinders grew into Plates, in a moft admirable and curious order, fo exceeding re- gular and delicate, as nothing could be more, as is vifible in ab^ac^a dy a e^afy but towards the end of fome of thefe ftems, they began again to grow finallerandto recover their former branchings, as about 4 and n,
10 Many of the lateral branches had collateral branches (if I may fb call them) as q m had many fuch as f ty and moft of thofe again fub- collateraly as v n?, and thefe again had others lefs, which one may call terojubcollateraly and thefe again others^ and they others, in greater Figures.
1 1 The branchings of the main Stems joyn’d not together by any re- gular line,nor did one fide of the one lie over the other fide of the other, but the fniall collateral and ^uhcoUateral branches did lie at top of one
O another
M I C RO G R A P H I A.
another according to a certain order or method, which I always obferv’d to be this.
12 That fide of a collateral or fubcollateral^ 8cc. branch, lay over the fide of the approximate (as the feathers in the wing of a Bird) whole branchings proceeded parallel to the laft biggeft ftem from which it (prung,and not to the biggeft ftem of all, unlels that were a fecond ftem backwards.
15 This rule that held in the branchings of the Sexa^gnlar Figure held allb in the branchings of any other great or fmall ftem, though it did not proceed from a center.
14 The exadlnels and curiofity of the figuration of thcfe branches, was in every particular fo tranfeendent, that I judge it almoft impoliible for humane art to imitate.
1 5 Tailing feveral deer pieces of this Ice^ I could not find any Vrin^ OHS tafte in them, but thofe few I tailed, feem’d as insipid as water.
16 A figuration Ibmewhat like this, though indeed in Tome particu- lars much more .curious, I have feveral times obferv’d in regulus martk fiellatus^ but with this difference, that all the ftems and branchings arc bended in a moll excellent and regular order, whereas in Ice the ftems and branchings are ftreight, but in all other particulars it agrees with this, and feems indeed nothing but one of thefe ftars,or branched Figures frozen on Vrine^ diftorted, or wreathed a little, with a certain propor- tion : Lead alfo that has Arfenick^ and Ibme other things mixt with it, I have found to have its lurface, when liiffer’d to cool, figured ibmewhat like the branchings of Vrine^ but much Imaller.
17 But there is a Vegetable which does exceedingly imitate thefe branches, and that is, Fearn^ where the main ftem may be obferv’d to (hoot out branches, and the ftems of each of thefe lateral branches, to fend forth collateral^ and thofe JubcoUateral^ and thofe latero jitbcollate- ral^ &c. and all thofe much after the lame order with the branchings, di- vifions, and fubdivifions in the branchings of thefe Figures in frozen Vrine 5 lb that if the Figures of both be well confider’d, one would ghels that there were not much greater need of a fiminal principle for the pro- duction of Fearn, then for the production of the branches of Vrine^ or the Stella martk ^ there feeming to be as much form and beauty in the one as in the other.
And indeed, this Plant of Fearn, if all particulars be well confider'd, will feem of as fimple, and uncompounded a form as any Vegetable, next to Mould or Mufljromes, and would next after the invention of the forms of thofe, deferve to be enquir’d into , for notwithftanding feveral have affirm’d it to have feed, and to be propagated thereby 5 yet, though I have made very diligent enquiry after that particular, I cannot find that there is any part of it that can be imagin’d to be more feminal then an- other : But this onely here by the by :
For the freezing Figures in Vrine, I found it requifite,
Firft, that the Superficies be not difturbed with any wind, or other commotion of the air, or the like-4
Secondly,
M I C R O G R A P H 1 Ai
Secondly^ that it be not too long expofed, fo as that the whole bulk be frozen-for oftentimes^in fuch cafesjby reafon of the fwelling the o^ Ice^ or from fome other caufe^ the curious branched Figures difappear.
Thirdly, an artificial freezing with Skoxv and Salt, apply d to the out- fide of the containing Veflel, fuceeeds not well, unlefs there be a very little quantity in the Vcfleh . / :
Fourthly, If you take any deer and fmooth Glais, and wetting all the infideofit with Vrine, you expofe it to a very fharp freezing, you will find it cover’d with a very regular and curious Figure* , , , ,
!L • : ^ •
I J . . V
Obfervables in figur'd Snow.
Expofing a piece of black Cloth, or a black Hatt to the falling Snow, I have often v/ith great pleafure, obferv’d fuch an infinite variety of cu= rioully figur’d Snow, thsx it would be asimpolfible to draw- the Figure and fhape of every one of them, as to imitate e:^adtly the curious and Geometrical of Nature in anyone. Some coorfe draughts,
fuch as the coldnefs of the weather, and the ill provifions, I had bype for fuch a purpofe, would permit me to make, I have here added in the Second F/^»re of the Eighth
In all which lobferv’d, that if they were of any regular Figure% they were always branched out with fix principal branches, all, of equal length,- fhape and make, from the center, being each of them inclin’d to eithej of the next branches on either fide of it, by an angle of fixty degrees.
Now, as all thefe ftems were for the moft part in one flake ex-adfly of the fame^^^make, fo were they in differing Figures of very differing ones 5 fb that in a very little time I have obferv’d above an hundred ley^fa^ cizes and fhapes of thefe ftarry flakes. , .j;
The branches alfb out of each ftem of jany one of thefe flakes, w.^^jc^- adfly alike in the fame flake j fb that of whatever Figure one of the branches were, the other five were.fiite to beof the fame, very ek^<ftly, that is, if the branchings of the one were finall Veralielipipeds or; I^lates, the branchings of the other five were of the fame, and generally^ the branchings were very conformable to the rules and method obferv’d be- fore, in the Figures on Vrine, that is^ the branchings from eagh fide ^of the ftems were parallel to the next ftem on that; fifig, /andiif tfip were plated, the branches alfb were the fmne, if the,ftem^ wetekvery: long, the branches a I fo were fo, ' ' iji .
Obferving fbrae of thefe figur’d flakes with a Mierpfiope, I fonnd thefn not to appear fb curious and exaftly figur’d as one would haye^int^gin'd, but like Artificial Figures, the bigger they were niagnify’d, thft ir*? regularites appear’d in them 5 but this irregularity feem’d; afojitifiablejtQ the thawing and breaking of the flake by the fall, and not, at all tOi (the defed of the virtue of Nature, whole curiofity in the forjnatiQn
ofmoftofthefeJkindofregularFigureSjfuchas thofeof Salt.Min4vM^s^t:»
O 2 appears
MiCROGR AP H lA.
appears by the help of the Mkrofeope^ to be very many degrees fmaller then the moft acute eye is able to perceive without it. And though one ofthefe fix-branched Stars appear’d here below much of the fhape de- (cribed in the Third Figure of the Eighth Scheme 3 yet I am very apt to think, that could we have a fight of one of them through a Microfeope as they are generated in the Clouds before their Figures are vitiated by external accidents, they would exhibit abundance of curiofity and neat- nefi there alfo, though never lb much magnify ’d : For fince I have ob- ferv’d the Figures o{ Salts and Minerals to be fome of them lb exceeding finall,that I have Icarcely been able to perceive them with the Microfeope^ and yet have they been regular, and fince (as far as I have yet examin’d it) there feems to be but one and the fame caule that produces both thele effeds, I think it not irrational to luppole that thele pretty figur’d Stars of Snovp^ when at firft generated might be allb very regular and exad.
III.
Several kinds of Figures in Wzter frozen.
Putting fair Water into a large capacious Veflel of Clafi, and expofing it to the cold, I oblcrv’d after a little lime, fevcral broad, flat, and thin laminse^ or plates of /ce, croffing the bulk of the water and one another very irregularly, onely moft of them feem’d to turn one of their edges to- wards that fide of the Glals which was next it, and feem’d to grow, as Were from the infide of the Veftel inwards towards the middle, almoft like lb many blades of Fern. Having taken leveral of thefe plates out of water on the blade of a Knife, I obferv’d them figur’d much after the Herring hones ^ or Fern blades^ that is, there was one bigger ftem in the middle like the back-bone, and out of it, on either fide, were a multitude of Imall fikri<^i or icicles^ like the Imaller bones,or the fmaller branches in Frr», each of thefe branches on the one fide, were parallel to all the reft on the lame fide, and all of them feem’d to make an angle with the ftem,towards the top, of lixty degrees, and towards the bot- tom or root of this ftem, of 1 20. See the fourth Figure of the 8. Plate.
I oblerv’d likewile leveral very pretty varieties of Figures in Water, frozen on the top of abroad flat Marble-ftone, expos’d to the cold with a little Water on it, Ibme like feathers, Ibme of other lhapes, many of them Were Very much of the lhape expreft in the fifth figure of thO 8. Stheme:, which is extremely differing from any of the other Figures.
* I oblerv’d likewile, that the Ihootings of Ice or\ the top of Water, be- ginning to ffeez, were in ftreight prijmatical bodies much like thole of rooh-pter^ that they croft eacn other ufually without any kind of order or rule, that they were always a little higher then the furface of the Wa- ter that lay between them $ that by degrees thofe interjacent fpaces would be fill’d with Ice alfo, which ullially would be as high as the liir- faoe ofthereft.
In flakes of ice that had been frozen on the topof Water to any con-
fiderable
1 c
R O G R A P H i A
fiderable thicknels, I obferv’d that both the tipper and the under lides of it were curioufly quilld, furrow’d, or grained, as it were, which when the Sun (hone on the Plate, was exceeding ea(ily to be perceiv’d to be much after the (hape of the lines in the 6. Figure cf the 8. Scheme^ thatis, they confilfed of leveral ftreight ends of parallel Plates, which were of divers lengths and angles to one another without any certain order.
The caufe of all which regular Figures (and of hundreds of others, namely of Salts^ Minerals^ Metals^ &c. which I Could have here inferted, would it not have been too long) feemstobe deducible from the fame Prindples,which I have (in the 13. OhfervatToh')hintcd on\y^ having not yet had time to compleat a Theory of them. But indeed (which I there al(b hinted) I judge it the fecond ftep by which the Pyramid of natu- ral knowledge (which is the knowledge of the form of bodies) is to beafeended: And whofoever will climb it, muft be well furnifh’d with that which the Noble Vernlam calls Scalam Intelle&us 5 he muft have fcaling Ladders, other wife the fteps are fo large and high, there will be no getting up them, and conlequently little hopes of attaining any higher ftation, fuchas to the knowledge of themoft fimple principle of Vegetation raanifefted in Mould and Mufbroraes, which, as I elfe- where endeavoured to (hew, feems to be the third (fep; for it feemsto me, that the Intelleft of man is like his body, deftitute of wings, and cannot move from a lower to a higher and more (ubliiiie ftation of know- lcdg,otherwi(e then ftep by ftep^nay even there where the way is prepar’d and already made pafiible , as in the Elements of Geometry^ or the like, where it is fain to climb a whole feries of Propefitions by degrees, before it attains the knowledge of one Prohkme. But if the afeent be high, dif- ficult and above its reach, it muft have recoiirfc to a novum organum^ (bme new engine and contrivance, (bme new kind of Algebra^ or Analy‘^ tick^ Art before it can (urmount it^
Obferv. X V. Of Kettcring-ftone, dnd of the fores (f In^i^ mate bodies,
THis Stone which is brought from Ketterihg in Northampton-flsireyLnd schm.
digg’dout of a Quarty,‘as I am inform’d, has a grain altogether admirable, nor have I ever (een or heard of any other ftone that has the ; like. It Is made up of an innumerable company of (mall bodies, not all : of the (ame cize or (hape, but for the moft part, not much differing frorii
: a Globular form, nor exceed they one another in Diameter above three
I or four times 5 they appear to the eye, like the Cobb or Ovary of a Her^
\ tring^ or feme (mailer fi(hes, but for the moft part, the particles (eeirt f fomewhat le(s, and not fo uniform 5 but their variation from a perfoft
f lobular ball,(eems to be only by the preflure of the contiguous bals which ave a little depreft and protruded thofe toucht fides inward, and forc’d
the
Micrographia.
the other fides as much outwards beyond the limits of a Globe 5 juft as it would happeOjif a heap of exadly round Balls of fbftClay were heap’d upon one another ^ or, as I have often feen a heap of fmall Globules of g^Htcksilver ^ reduc’d to that form by rubbing it much in a glaz’d Vcflel, with feme llimy or lluggifh liquor, fuch as Spittle, when though the top of the upper Globules be very neer fpherical, yet thofe that are preft upon by others , exadly imitate the forms of thefe lately mention’d grains.
Where thefe grains touch each other, they are (b firmly united or fettled together, that they feldom part without breaking a hole in one or th’other of them, luch as &c. Some of which fradions,
as rf, <?, a, where the touch has been but light, break no more then the outward cruft, or firft (hell of the ftone, which is of a white colour, a little dafh’d with a brownifti Yellow,and is very thin,like the (hell of an Egg : and I have feen fomc of thofe grains perfeftly relemble fome kind of Eggs, both in colour and lhape : But where the union of the contiguous granules has been more firm, there the divulfion has made a greater Chafm, as at /», in fo much that I have obferv’d fomc of them quite broken in two, as at c, c, c, which has dilcovered to me a further refem- blance they have to Eggs,they having an appearance of a white and yelk, by two differing lubftances that envelope and encompaft each other.
That which we may call the white was pretty whitifh neer the yelk, but more dufkie towards the fhell 3 Ibme of them I could plainly per-^ ceivc to be (hot or radiated like a Pj/rites or fire-jione 3 the yelk in Ibme I law hollow, in others fill’d with a dufkie brown and porous fiib- ftance like a kind of pith.
The fmall pores, or interjiitia e e e e betwixt the Globules, I plainly faw,and found by other trials to be every way pervious to air and water, for I could blow through a piece of this ftone of a confiderable thicknefs, as eafily as I have blown through a Cane, which minded me of the pores which Des Cartes allow his materia Jubtilis between the athereal globules.
The objedf, through the Microfeope^ appears like a Congeries or heap of Pibbles, flich as I have often feen caft up on the ftiore, by the w-orkr ing of the Sea after a great ftorm, or like (in fhape, though not colour) a company of fmall Globules of Quickfilver, look’d on withxMicrofiopej when reduc’d into that form by the way lately mentioned. And per- haps, this laft may give fbme hint at the manner of the formation of the former ; For fuppofing fbme Lapiclejcent fubftance to be generated, or fbme way brought (either by fbme commixture of bodies in the Sea it folf, or protruded in, perhaps, out of fbme Jubterraneous caverns) to the bottom of the Sea,and there remaining in the form of a liquor like C^uick- filver, heterogeneous to the ambient Saline fluid, it may by the working and tumblings of the Sea to and fro be jumbled and comminuted into fuch Globules as may afterwards be hardned into Flints, the lying of which one upon another, when in the Sea, being not very hard, by rca- fbn of the weight of the incompalling fluid, may caufe the undermoft to be a little,though not much, varied from a globular Figure. But this only by the by. After
Micrograph lA,
After what manner this Ketterwg-flone Ihould be generated I cdnrlot learn, having never been there to view the place, and oblervethccir- cumftances ^ but it feems tome from the ftrudlurc of it to be generated from fome fubftance once more fluid, and afterwards by degrees growing harder, almoft after the fame manner as I flippofed the generation of Flints to be made.
But whatever were the caufe of its curious texture, we may learn this information from it 5 that even in thole things which we account vile, rude,and coorlc. Nature has not been Wanting to fhew abundance of cu- riofity and excellent Mechanilme.
We may here find a Stone by help of a Microfeope, to be made up of abundance of fmall Balls, which do but juft touch each other, and yet there being lb many contafts,they make a firm hard mals, or a Stone much harder then Free-ftone.
Next, though we can by a Mkrofiope dilcern lb curious a Ihape in the particles, yet to the naked eye there ftarce appears any luch thing'5 which may affbrd us a good argument to think, that even in thole bodies allb, whole texture we are not able to dilcern, though help’d with Micros fcopes. there may be yet latent lb curious a Schematifme^ that it may abun* dantly fatisfie the curious fearcher, who lhall be lo happy as to find fome way to difoover it.
Next, we here find a Stone, though to the naked eye a very dole one, yet every way perforated with innumerable pores, which are nothing elfo but the yV/^er^ft^jbetween thole multitudes of minute globular particles, thatcompofe thebulkitfelf, and thefe pores are not only difeovefd by the MkroJcopCy but by this contrivance.
I took a pretty large piece of this ftone, and covering it all over with cement, lave only at two oppolite parts, I found my lelf able, by blowing in at one end that was left open, to blow my fpittle, with which I had wet the other end, into abundance of bubbles, which argued thefe pores to be open and pervious through the whole ftone, which affords us a very pretty inftance of the poroulhefs of fome leemingly dole bodies,of which kind I lhall anon have occalion to lubjoyn many more, tending to prove the fame thing.
I rauft not here omit to take notice, that in this' body there is not a vegetative that Ihould fo contrive this ftrudure for any peculiar
ufo of Vegetation or growth, whereas in the other inftances of vegetable porous bodies, there is an anima^ or forma inf or mans, that does contrive all the Strudures and Mechanifmes of the conftituting body, to make them fubfervient and ufcfull to the great Work or Fundion they are to perform. And lb I ghds the pOres in Wood, and other vegetables, in bones,and other Animal fubftances,to be as fo many channels,provided by the Great and Alwile Creator, for the conveyance of appropriated juyees to particular parts. And therefore,that this may tend, or be pervious all towards one part,and may have impedimcnts,as valves or the like, to any other 3 but in this body we have very little reafon to fulped there fhould be any foch defign, for it is equally pervious eveiy way, not onely for-
I
M I C RO G R A P H I A.
ward, but backwardsjand fide- ways, and Teems indeed much rather to be Homogeneom or fimilar to thofe pores, which we may with great proba- bility believe to be the channels of bodies, not dirediied, or more open any one way, then any other, being equally pervious every way. And, according as thefe pores are more or greater in refped of the in- terfiitial bodies, the more tranlparent are the To conftituted concretes 5 and the finaller thofe pores are, the weaker is the Impulfe of light com- municated through them, though the more quick be the progrels.
Upon this Occafiorjj I hope it will not be altogether unfeafonable, if I propound my conjectures and Hypothejis about the medium and con- veyance of light.
I fuppofe then, that the greateft part of the Interjlitia of the world, that lies between the bodies of the Sun and Starrs, and the Planets, and the Earth, to be an exceeding fluid body , very apt and ready to be mov’d, and to communicate the motion of any one part to any other part, though never To far diftant ; Nor do I much concern my felf, to deter- mine what the Figure of the particles of this exceedingly fubtile fluid medium muft be 5 nor whether it have any interftitiated pores or vacui- ties,it being fufficient to folve all the Vh^uomena to liippofe it an exceed- ingly fluid, or the moft fluid body in the world, and as yet impofiible to determine the other difficulties.
That being lb exceeding fluid a body, it eafily gives pajflage to all other bodies to move to and fro in it. •
That it neither receives from any of its parts, or from other bodies, nor communicates to any of its parts, or to any other body, any impulfe, or motion in a direCt line, that is not of a determinate quicknefs. And that when the motion is of fuch determinate fwiftnels, it both receives, and communicates, or propagates an impulfe or motion to any imaginable diftancein ftreight lines, with an unimaginable celerity and vigour.
That all kind of Iblid bodies confift of pretty maflie particles in re- IpeCt of the particles of this fluid medium^ which in many places do To touch each other,that none of this fluid medium interpofes much after the fame mannner (to ufe a grofs fimilitude) as a heap of great ftones compafi one great cotjgerm or mafs in the midfl: of the water.
That all fluid bodies which we may call tangible^ are nothing but Ibmc more fubtile parts of thofe particles, that ferve to conftiture all tangible bodies.
That the water, and fiich other fluid bodies, are nothing but a congeries of particles agitated or made fluid by it in the lame manner as the particles of Salt are agitated or made fluid by a parcel of water, in which they are diflblv’d, and fubfiding to the bottom of it, conftitute a fluid body, much more maflie and denlc, and left fluid then the pure water it felf
That the air on the other fide is a certain company of particles of quite another kind, that is, fuch as are very much fmaller, and more eafiely moveable by the motion of this fluid medium 5 much like thofe very lub- tile parts of techenel^mdi other very deep tinging bodies,whcre by a very
fmall :
Micrographiaj
final! parcel of matter is able to tinge and diffule it felf Over a very great
quantity of the fluid diflblvent 5 or Ibmewhat after that mannerj as finoakj and fuch like minute bodies, or fteams, are obferv d to tinge a very great quantity of air j onely this lafl: iimilitude is deficient in one propriety, and that is a perpetuity or continuance in that ftare of com- mixture with the air, but the former does more neerly approach to the nature and manner of the air s being diflblv'd by this fluid or JEthen And this Similitude \vill flirther hold in thefe proprieties 5 that as thole tindiures may be increaled by certain bodies,fo may they be precipitated by others 5 as I lhall afterwards Ihew it to be very probable, that the like accidents happen even to the Air it felf
Further, as thele Iblutions and tindures do alter the nature of thcle fluid bodied, as to their aptnels to propagate a motion or impulfe through them, eveh lb does the particles of the Air, Water, and other fluid bo- dies, and of Clafi, Cryfial, €^c. which are cominixt with this bulk of the j£ther^ alter the motion of the propagated pulfe of light ; that is, where thefe more bulkie particles are more plentifull, and confequently a lefler quantity of the JEther between them to be mov’d ,there the motion muft necefiarily be the fwiftcr,though not fo robuft, v/hich will produce thole effeds, which I have (I hope) with Ibme probability, aferibed to it in the digreliioh about Colours, at the end of the obfirvatiom on fiovy-glaff.
Now, that other Stones, aiid thole which have the cloleftand hardeft textures, and leem (as far as we are able to difeover with oUr eyes, though help’d with the bell Mkrofe apes') freefi: from pores, are yet not° withftanding replenifh’d with them , an Inflance or two Will, I luppofe, make more probable.
A very Iblid and iinflaw’d piece bfcleer white Marble^ Wit be well polilh’d and glaz’d, has lb curioufly Iraooth a furface, that the beft and moft polilk’d lurface of any wrought-glals, feems not to the naked eye, nor through a Mkrofeope^ to be more Imooth, and leis porous. And yet, that this hard dole body is replenilh’d with abundance of pores, I think thefe following Experiments will fufficicntly prove,
The.firfl: is. That if you take fuch a piece, and for a pretty While boyl it in Turpentine and Oyl of Turpentine, you lhall find that the ffone will be all imbu’d with it 5 and whereas before it look’d more white, but more opacouS, now it will look more greafie, but be much more tranfparent, and if you let it lie but a little While, and then break off a part of it, you lhall find the Undhibus body to have penetrated k to fuCb a determinate depth every way within the lurfaCe, This may be yet eafier try’d with a piece of the lame Marble^ a little V/afm’d in the fire, and then a Iktle Pitch or Tarr melted on the top of it 5 for thefe black bodies, by their rnfinu- adng themfelves into the invifible pores of the ftone, ting it with lb black a hue, that there can be no further doubt of the truth of this afleftion, that it abounds with finall imperceptible pores; .
Now, that other bodies will allb fink into the pores of Mar'bh^ befioes unQu&ffs^ I have fry’d, and found, that a very Blue tindure made irt
p
^8 M I C R O G R A P H I A.
JpiritcfVrme would very readily and eafily fink, into it, as would alio fcveral tinftures drawn with Jpirit of IVine.
Nor is Marble the only feemingly clofe ftone, which by other kinds of Experiments may be found porous 5 for I have by this kind ofExperi- ment on divers other (tones found much the fame eftc6t, and in Ibme, in- deed much more notable. Other (tones ! have found fo porous, that with the Mkrofcope I could perceive feveral finall winding holes, much like Worm-holes,as I have noted in fome kind of Purbeckfione^ by looking on the (urface of a piece newly flaw’d ofF^ for if otherwife, thelurface has been long expos’d to the Air, or has been feraped with any tool , thole (mall caverns arc fill’d with du(t,and difappear.
And to confirm this ConjeBure^ yet further,! (hall here infert an excel- lent account, given into the Royal Society by that Eminently Learned Phy- fician, Dodtor Goddard^ of an Experiment, not lefs inftrudive^hen curi- ous and accurate, made by hirafelf on a very hard and (eemingly dole (lone call’d Oculus Mundi^ as ! find it preferv’d in the Records of that Honourable Society.
A fmall ftone of the kind, call’d by fome Authours, Ocului Mundiy being dry and cloudy, weigh’d 5 Grains.
The fame put under water for a night, and fomewhat more, became tranfparent, and the fuperficies being wiped dry, weighed 6 ^ Grains,
The difference between thefe two weights, o ^of a Grain.
The fame Stone kept out of water one Day and becoming cloudy again weighed, 5^ Grams.
Which was more then the firft weight, of a Grain.
The fame being kept two Days longer weighed, Grams.
Which was lefs then at firft, of a Grain.
' i 56
Being kept dry fomething longer it did not grow fenfibly lighter.
Being put under water for a night and becoming again tranf. parent and wiped dry, the weight was, Grains^ the fame with the firft after putting in water, and more then the laft weight after keeping of it dry, of a Grain.
Another Stone of the fame kind being variegated with milky Mte and graj like fome forts of Agates^ while it lay under water, was alwaies invironed with little Bubbles, fuch as appear in '
water
Micrographia.
water a little before bciyling, next tfie fides of the Veflel.
There were alfo fome the like Bubbles on the Surface of the water juft over it, as if cither fdme exhalations came but of it, or that it did excite fome fermentation in the parts of the water contiguous to it.
There was little fenfible difference in thetranfparcncy of this Stone, before the putting under water, and after ; To be fure the tmV&j-whke parts continued as before, but more difference in weight then in the former. For whereas before the putting into the water the weight was 1 8 Graims, After it had lyen in about four and twenty hours the weight was 20^ Grmes^ fo the difference was, i ^ Graines,
The fame Stone was infufed in the water fcalding hot, and fo continued for a while after it was cold, but got no more weight then upon infufing in the cold, neither was there any fenfible Diffoence in the weight both times.
In which Experimentjthere are three Obfervablesjthatfeem very roani- feftly to prove the poroufneft of thefe fecmingly dole bodies ; the firft is their acquiring a tranlparency, and lofing their whitenels afrer/teeping in water, which will feem the more ftrongly to argue it, if what I have already laid about the making tranfparent, or clarifying of Ibme bodies, as the white powder of beaten Glals, and the froth of Ibme glutinous tranlparent liquor be well confider’d ^ for thereby it will leem rational to think that this tranfparency arifes from the infinuation of the water (which has much the lame refraftion with fuch ftony particles, as may be dilcoverd by Sand view’d with a Microfiope)into thole pores which were formerly repleat with air (that has a very differing refradfion, and con- lequently i^ very refledfive) which feems to be confirm’d by the lecond ObferVable, namely, theinerealeof weight after Ifeeping, and decreale upon drying. And thirdly,feem’d yet more fcnfibly confirm’d by the mul- titude of bubbles in the lalt Experiment.
Wc find allb moft Acid Salts very readily to dilfolvc and feparate the parts of thbbody one from another 5 which is yet a farther Argument to confirm the poroiifibefs oi bodies, and will ferve as liich, to Ihew that even Glals alfo has an abundance of pores in it,fince there are feveral li- quors, that with long flaying in a Glafi, will lb CarrocU and cat into it, as atlaft, to^makeit pervibus fo the liquor it contain’d, of which I have feen very many Inllances. ' .
Since therefore we find by other prqoft, that many of thc^ bodies
P 2 which
100 M ICR OGR AP H lA.
which wc think the moft folid ones, and appear fo to our fight, have not- withftanding abundance of thofe grofler kind of pores, which will ad- mit leveral kinds of liquors into them, why fliould we not believe that Clafs, and all other tranfparent bodies abound with them,fince we have many other arguments, befides the propagation of light, which feem to argue for it ?
And whereas it may be objeded, that the propagation of light is no argument that there are thofe atomical pores in glafs, fince there are Hy- pothefes plaufible enough to folve thofe Fh£nomena^ by fiippofing the pulfe onely to be communicated through the tranfparent body.
To this I anfwer, that that Hypothejis which the induftrious Moreanuf has publifti'd about the flower motion of the end of a Ray in a denfer wedinm^thtn in a more rare and thin,feems altogether unfufEcient to folve abundance of Vhanomena^ of which this is not the leaft confidcrablejthat it is impoflible from that luppofition, that any colours fliould be gene- rated from the refradion of the Rays, for fince by that Hypothecs the undulating pulfe is always carried perpendicular, or at right angles with the Ray or Line of diredion,it follows, that the ftroke of the pulfe of light, after it has been once or twice refraded (through a Prifine,for ex- ample) muft affed the eye with the fame kind of ftroke ^s if it had riot been refraded at all. Nor will it be enough for a Defendant of that Hy~ pothejis^ to fay, that perhaps it is becaufo the refradions have made the Rays more weak, for if fo, then two refradions in the two parallel fides of a §^adr angular Prijke would produce colours, but we have no fuch Vhdmntena product.
There are foveral Arguments that I could bring to evince that there are in alj tranfparent bodies fuch atomical pores. And that there is fuch a fluid body as I am arguing for, which is the medium^ or Inftrument, by which the pulfe of Light is convey’d from the lucid body to the en- lightn’d. But that it being a digreflion from the Oblervations I was re- cording, about the Pores oi Kettering Stone ^ it would be too much fuch, if I fhould protrad it too long, and therefore I fhall proceed to the next Obfervation,
Obferv. XVI. Charcoal, pr Vegetables.
CHarcoaljOr a Vegetable burnt black,aflbrds an ob)cd[no left pleafant than inftrudive 5 for if you take a fmall round Charcball,^nd break itlhort with your fingers, you may perceive it to break 'with a very finooth and fleekfurtace, almoftlikethcfurfece of blackfeahng Wax ^ this furface,if it be look’d on with an ordinary does manifeft
abundance of thofe pores which are alfo vifible’to the eye in many kinds of Wood^ rang’d round the pith, both a in kind of circular order, and a radiant one. Of thefc there are a multitude in the fubftance of the Coal, every where almoft perforating and drilling it from end to end^ by
means
Micrographia* lOi
means of which, be the Coal never fo long, you may eafily blow through it 5 and this you may prefcntly find, by wetting one end of it with Spittle, and blowing at the other.
But this is not all, for befides thofe many great and confpicuous irre- gular Ipots or pores, if a better Microfcope be made ule of, there will ap- pear an infinite company of exceedingly fmall, and very regular pores, lb thick and fo orderly fet, and fo clofe to one another, that they leave very little room or fpace between them to be fill’d withafolid body,for the apparent >ir7terjiitia^ or feparating fides ofthefe pores feem fo thin in fome places, that the texture of a Honey-comb cannot be more porous. Though this be not every where fo, the intercurrent partitions in fome places being very much thicker in proportion to the holes.
Mofi: of thefe fmall pores feem’d to be pretty round, and were rang’d in rows that radiated from the pith to the bark 5 they all of them leem’d to be continued open pores, running the whofo length of the Stick 5 and that they were all perforated , I try’d by breaking off a very thin Oiver of the Coal crols-ways, and then with my diligent-
ly furveying them againft the light, for by that means I was able to fee quite through them.
Ihefe pores were fo exceeding fmall and thick,that in a line of them, j-g part of an Inch long, I found by numbring them no lefs then 150. linall pores j and therefore in a line of them an Inch long, muft be no lels then 2700. pores, and in a circular area of an Inch diameter, muft be about 5725350. of the like pores 5 fo that a Stick of an Inch Diameter, may containe no lefs then feven hundred and twenty five thonfand, be- fides 5 Millions of pores, which would, I doubt not, feem even incredible, were not every one left to believe his own eyes. Nay, having fince ex- amin’d Cocus^ blacky and green Ebony ^Lignnm Vita I found, that all
thefe Woods have their pores, abundantly fmaller then thofe of foft light Wood 5 in fo much, that thofe of Guajacum feem’d not above an eighth part of the bignefs of the pores of Beech, but then the Interjiitia were thicker 5 fo prodigioully curious are the contrivances, pipes, or fluces by which the Succtfs nntritius^ or juyee of a Vegetable is convey’d from place to place.
This Obfenvation feems to afford , us the true reafon of feveral Pha- nomend of Coals 5 as r
Firft, why they look black 5 and for this we need go no further then the scheme^ lor certainly, a body that has fo many pores in it as this is dif- cover’d to have, from each of which no light is reflefted, muft ncceflarily look black, cfpccially, when the poxes are fome what bigger in proporti- on to the intervals themthey are cut in the Scheme^ black being nothing elfe but a privation of Light, or a want of reflection 5 and wherefover this reflecting quality is deficient, there does that part look black, whe- ther it be from a pordufhefs of the body,as in thisInftance,or in adeadning and dulling.quality,.fuchas I have obferv’d in the Scoria, of Lead, Tin, Silver, Copper, ^ •
Next, we may alfo as plainly fee the reafon of its fhining quality, and
that
2 M I CROGR A PH I A.
that is from the even breaking off of the ftick, the folid interflitia having a regular termination or furface, and having a pretty ftrong re- hefting quality, the many fmall refleftions become united to the n^ed eye, and make a very pretty (hining furface.
Thirdly ,the reafon of its hardnefs and brittlenels (eems evidentjfor’fince all the watery or liquid fubftance that moiftn’d and toughn’d thofe Inter- fiitia of the more lolid parts, are evaporated and remov’d, that which is left behind becomes of the nature almoft of a ftone, which will not at all, or very little,bend without a divuljion or Jblntion of its continuity.
It is not my defign at prefent, to examine the ule and Mechanifnie of thefe parts of Wood, that being more proper to another Enquiry 3 but rather to hint, that from this Experiment we may learn,
Firft, what is the caufe of the blacknefs of many burnt bodies, which we may find to be nothing elle but this 3 that the heat of the fire agi- tating and ratifying the watcrifh, tranfparent, and volatile water that is contain’d in them,by the continuation of that aftion,docs fo totally expel and drive away all that which before fill d the pores, and was dilpers’d allb through the folid mafe of it, and thereby caus’d an univerfal kind of tranlparency, that it not onely leaves all the pores empty, but all the In- terfiitia alfo fo dry and opacouf, and perhaps alfo yet further perforated, that that light oncIy is reflefted back which falls upon the very outward edges of the pores, all they that enter into the pores of the body, never returniHg, but being loft in it.
Now, that the Charring or coaling of a body is nothing elfe, may be cafily believ’d by one that (hall confider the means of its produftion, which may be done after this, or any (iich manner. The body to be chart’d or coal’d, may be put into a Cr»c/^/e,Pot,or any other Veflel that will endure to be made red-hot in the Fire without breaking, and then cover’d over with Sand, fo as no part of it be (uffer’d to be open to the Air, then let into a good Fire, and there kept till the Sand has continu’d red hot for a quarter, half, an hour or two, or more, according to the nature and bigneft of the body to be coal’d or chair’d, then taking it out of the Fire,and letting it ftand till it be quite cold, the body may be taken out of the Sand well chart’d and cleans’d of its waterifh parts 5 but in the taking of it out, care muft be had that the Sand be very neer cold, for elfo, when it comes into the free air, it will take fire, and readily burn away.
This maybe done alfo in any dole Veflel of Glals,as a Retort, of the like, and the feveral fluid fubftances that come over may be receiv’d in 2. ht Recipient, which will yet further countenance this : And
their manner of charring Wood in great quantity comes much to the fame thing, namely, an application of a great heat to the body, and preferving it from the free accels of the devouring air 3 this may be cafily learn’a from the Hiftory of Charring of Coal, moft excellently defer ib’d and publifli’d by that moft accomplifh’d Gentleman, ? Mr. John Bvelin, in the 100, loi, 105, pages of his Sylva, to which I (hall therefore refer the cu- rious Header that defires a full information of it.
Next
Micrographia. 1
Next, we may learn what part of the Wood it is that is the comhujlibie matter , for fince we (hall find that none, or very little of thole fluid fub“ ftances that are driven over into the Receiver are combujiible^ and that moft of that which is left behind is fo,it follows, that the folid interjiitja of the Wood are the combnjiible matten Further, the reafori why un- charr’d Wood burns with a greater flame then that which is charr'd, is as evident, becaufe thofe waterilh or volatil parts ifluing out of the fired Wood, evety way, not onely (hatter and open the body, the better for the fire to enter, but ifluing out in vapours or wind, they become like fo many little aolipiles^ or Bellows, whereby they blow and agitate the fir’d part, and conduce to the morefpeedy and violent eonfumption or diflblution of the body.
Thirdly, from the Experiment of dharring of Coals (whereby we (ee that notwithflanding the great heat, and the duration of it, the (olid parts of the Wood remain, whilefl: they are preferv’d from the free accels of the air iindiflipated) v;e may learn,that which has not,that I know o^ been publi(h’d or hinted, nay^ not fo much as thought of, by any 5 and that in (hort is this.
Firft, that the Air in which we live, move, and breath, and which en- compafles very many, and cherifhes mofl: bodies it encompafles, that this Air is the «?e/^r»»«?,or univerlal diflblvent of all Sulphureous bodies.
Secondly, that this aBion it performs not, till the body be firfl: fuffi= ciently heated, as we find requifite alfo to the diflblution of many other bodies by (everal other meujiruums.
Thirdly, that this aBion of diflblution, produces or generates a very great heat,and that which we call Fire 5 and this is common allbtomany diflblutions of other bodies, made by menfirunms^ of which I could give multitudes of Inflances.
Fourthly, that this aBion is perform’d with (b great a violence, and does (b minutely aft, and rapidly agitate the fmallefl: parts of the com-^ matter, that it produces in the diaphanous medium oi the Air, the aftion or puKe of light,which what it is, I have elfe-where already (hewn.
Fifthly,/^dt the dijjolution of (ulphureous bodies is made by a (ublfance inherent, and mixt with the Air, that is like, if not the very fame, with that which is fixt mSalt-peter^ which by multitudes of Experiments that may be made with Saltpeter^WiW^ I think,moft evidently be demonftrated.
Sixthly, that in this dijfblution of bodies by the Air, a certain part is united and mixt, ordifiTolv’d and turn’d into the Air, and made to fly up and down with it in the fame manner as a metalline or other body difl Iblv’d into any menfiruums^ does follow the motions and progrefles of that menjiruum till it be precipitated.
Seventhly, That as there is one part that is diflbluble by the Air,(b are there other parts with which the parts of the Air mixing and uniting, do make a Coagulum^ or precipitation^ as one may call it, which caufes it to be (eparated from the Air, but this precipitate is (b light, and in fo fmall andrarify’d or porous clufters, that it is very volatil, and iseafily carry ’d up by the motion oftW Air^though afterwards,when the heat and
agitation
4 M I C RO G R A P H I A.
agitation that kept it rarify’d ceafes^it eafily condenfes,and commixt with other indiflbluble parts, it flicks and adheres to the next bodies it meets withall ^ and this is a certain Salt that may be extraded out o^Soot» Eighthly, that many indiflbluble parts being very apt and prompt to be rarify’d, and fb, whilefl: they continue in that heat and agitation, are lighter then the Ambient Air, are thereby thrufl and carry’d upwards with great violence, and by that means carry along with them, not onely that Saline concrete I mention’d before, but many terreflrial, or indif^ folublc and irrarcfiable parts, nay, many parts alfo which are diflblubic, but arc not fuflfer’d to flay long enough in a fufficient heat to make them prompt and apt for that adion. And therefore we find in soot^ not onely a part, that being continued longer in a competent heat, will be d\t- folv’d by the Air, or take fire and burn ^ but a part alfo which is fixt, ter- reftrial, and irrarcfiable.
Ninthly, that as* there are thefe fevcral parts that will rarifie and fly, or be driven up by the heat, fo are there many others, that as they are indiflbluble by the aerial n/enjirmmjo are they of fuch fluggifh and grofi parts, that they are not eafily rarify’d by heat, and therefore cannot be rais’d by it 5 the volatility or fixtnels ofa body feeming to confifl only in this, that the ‘One is of a texture, or has component parts that will be eafily rarify’d into, the form of Air, and the other, that it has fuch as will not, without much ado,be brought to fuch a conflitution 5 and this is that part which remains behind in a white body call’d Afhes, which contains a fubflance,or .J4/r, which Chymifls call All(ali:what the particular natures ofeachofthefe bodies are, I fhall not here examine, intending it in an- other place,but fhall rather add that this Hypothejis does fo exadly agree with Phenomena of Fire, and fo genuinely explicate each particular circumflance that I have hitherto obferv’d, that it is more then probable, that this caufe which I have aflign’d is the true adequate, real, and onely caufe of thofe Phenomena 5 And therefore I fhall proceed a little fur- ther, to fhew the nature and ufe of the Air.
Tenthly, therefore the diflblving parts of the Air are but few,that is, it feems of the nature of thofe Saline mcnjlrmms, or fpirits, that have very much flegme mixt with the fpirits, and therefore a fmall parcel of it is quickly glutted, and will diflblve no more 5 and therefore unlefs feme frefh part of this ntenfiruum be apply ’d to the body to be diflblv’d, the aftion ceafes, and the body leaves to be diflblv’d and to fhine, which is the Indication of it, though plac’d or kept in the greatefl heat, whereas Salt-peter is a menjirnum^ when melted and red-hot, that abounds more with thofe Diflblvent particles, and therefore as a fmall quantity of it will diflblve a great fulphureous body, fo will the diflblution be very quick and violent.
Therefore in the Eleventh place, it is obfervable, that, as in other folutions, if a copious and quick fupply of ffefti menfirmm^ though but weak, be poured on, or applied to the diflbluble body, it quickly con- femes it : ^ this menjirnum of the Air, if by Bellows, or any other fuch contrivance, it be copioufly apply’d to the Ihining body, is found to
diflblve
MlCROGRAPHiA.
diflblvc it as (bon, and as violently as the more ftrong menjiruHfJi of melted Nitre.
Therefore twelfthly, it feenis reafbnable to think that there is no fuch thing as an Element of Fire that Ihould attraftor draw up the flame, or towards which the flame fhould endeavour to afeend out of a defire or appetite of uniting with that as its Homogetieal primitive and generating Element ^ but that that fhining tranfient body which we call Flame^ is nothing clfe but a mixture of Air, and volatil fulphureous parts of dido- luble or combuftible bodies, which are ading upon each other whil’d they afeend, that is, flatne feems to be a mixture of Air, and the com- buftible volatil parts of any body, which parts the encompaffing Air does diflblve or work upon, which aftion,as it does intend the heat of the aerial parts of the diflblvent,fo docs it thereby further rarifie thofe parts that are afting, cr that are very neer them, whereby they growing much lighter then the heavie parts of that Menjiruum that are more remote,arc thereby protruded and driven upward , and this may be eafily obferv'd alfb in diflplutions made by any other menjirnnm^ efpecially fuch as either create heat or bubbles. Now, this aftion of the or Air^ on the
diflbluble parts, is made with fuch violence, or is fuch, that it imparts liich a motion or pulfe to the diaphanous parts of the Air, as I have elfe- where fhewn is requifite to produce light.
T\{\s Hypothejis I have endeavoured to raife from an Infinite ofObfer- vations and Experiments, the procefs of which would be much too long to be here inferred, and will perhaps another time afford matter copious enough for a much larger Difeourfe , the Air being a Subjedt which (though all the world has hitherto liv’d and breath’d inland been uncon- verfant about)has yet been fo little truly examin’d or explain’d,that a di- ligent enquirer will be able to find but very little information from what has been (till of late) written of it ; But being once well underftood, it will, I doubt not, inable a man to render an intelligible, nay probable, if not the true reafbn of all the Ph£nomena of Fire, which, as it has been found by Writers and Philofophers of all Ages a matter of no finall dif ficulty, as may be fufficiently underftood by their ftrahge Hypothejes^ and unintelligible Solutions of Ibme few Phenomena of it 5 fb will it prove a matter of no fmall concern and ufe in humane affairs, as I fhall elfewhere endeavour to manifefi: when I come to fhew the ufe of the Air in refpi- ration, and for the prefervation of the life, nay, for the confervation and reftauration of the health and natural conftitution of mankind as welfas all other aereal animals^ as alfo the ufes of this principle or propriety of the Air in chymical, mechanical, and other operations. In this place I have onely time to hint an Hypothecs, which, if God permit me life and opportunity, I may elfewhere profecute, improve and publifli. In the mean time, before I finifh this Difeourfe, I muft not forget to acquaint the Rcader,that having had the liberty granted me of making feme trials on a piece of Lignum fojjile (hewn to the Royal Society, by the eminently Ingenious and Learned Phyfician, Dodor who receiv’d it for a Pre- lent from the famous Ingeniofo Cavallhro de Pozziyt being one of the fairelt
lO^ M1CROGR.APHIA.
and beft pieces of Lignum fojfile he had feen , Having (I fay) taken a fmall piece of this Wood, and examin’d it, I found it to burn in the open Air almoft like other Wood, and infteed of a refinous fmoak or fume, it yielded a very bituminous one, Imelling much of that kind of lent ; But that which I chiefly took notice ol, was, that cutting off a fmall piece of it, about the bignels of my Thumb, and charring it in a Crucible with Sand, after the manner I above prcfcrib’d, I found it infinitely to abound with the Iraaller fort of pores, fo extreme thick, and fo regularly perfo- rating the fubftance of it long- ways, that breaking it off a-crols, I found it to look very like an Honey-comb ^ but as for any of the fecond, or bigger kind of pores, I could not find that it had any 5 fo that it feems, whatever were the caufo of its produftion, it was not without thofe linall kind of pores which we have onely hitherto found in Vegetable bo- dies : and comparing them with the pores which I have found in the Char- coals that I by this means made of feveral other kinds of Wood, I find it refomble none fo much as thofe of Firr, to which it is not much unlike in grain alfo, and feveral other proprieties. ^
And therefore, what ever is by fomc, who have written of it,and parti- cularly by Francijco Stel/uto^who wrote a Trcatife in Italian of that Sub- jeft, which was Printed dXRome^ 1637* affirm’d that it is a certain kind of Clay or Earth, which in trad of time is turn’d into Wood,I rather fufped the quite contrary, that it was at firft certain great Trees of Fir or Pine, which by fome Earthquake, or other cafualty, came to be buried under the Earth,and was there,after a long time’s refidence(according to the fo- veral natures of the encompafling adjacent parts)either rotted and turn’d into a kind of Clay, or petrify d and turn’d into a kind of Stone, or elfo had its pores fill’d v^ith'^Certain Mineral juices,which being ftayd in them, and in trad of timecoagulatcd, appear’(i, upon cleaving out,likc fmall Metaline Wires, or elfo from fome flames or Icorching forms that arc the occafion oftentimes,and ufoally accompanyEarthquakes,might be blafted and turn’d into Coal, or elfo from certain fubterraneous fires which arc affirm’d by that Authour to abound much about thofe parts (namely, in a Province of Italy^ call’d Vmbria, now the Dutchie of Spoletto, in the Territory of T<7^/7,anciently call’d T«£/<?r3and between the two Villages of Co//efecco3indRofaronot fardiftant from the high-way leading to Rome, where it is found in greater quantity then elfowhere)are by reafon of their - being cncompaflfed with Earth, and fo kept clofo from the diflblving Air, charr’d and converted into Coal. It would be too long a work to de- foribe the feveral kinds of pores which I met withall, and by this means difoovered in feveral other Vegetable bodies ^ nor is it my prefont defign to expatiate upon Inftances of the fame kind, but rather to give a Spe- cimen of as many kinds as I have had opportunity as yet of obferving, re- forving the profocution and enlarging on particulars till a more fit op- portunity 3 and in profocution of this defign, I (hall here add :
Oblerv.
Schcm:^.
M
ICROGRAPH lA.
Obfcrv. XVII, Of Petrify ’d wood, anJothet^etrlffd bodicso
OF this fort of fubftance, I obferv’d feveral pieces of very differing kindsj both for their outward fhape, colour, grain, texture^ hard- nefi, feme being brown and redifh 5 others gray, like a Hone 5 others black, and Flint-like : fome foft,like a Slate or Whetftoiie, others as hard as a Flint, and as brittle. That which I more particular exafnin’d,was a piece about the bignels of a mans hand, which feem’d to have been a part of feme large tree, that by rottennefs had been broken off fr6m it before it began to bepe^nj^' <5^.
And indeed, all that I have yet feen, feem to have been rotfen Wood before the petrifadcion was begun ; and not long fince, examining add viewing a huge great that feem’d with meer age to be rotten as it ftood, I was very much confirm’d in this opinion , for I found, that the grain, colour, and fhape of the Wood, was exadily like thispe/r^Wfiib- fiance ^ and with a Mkrojeope, I found, that all thofe Microfeopical pores, which in fappy or firm and found Wood are fill’d with the natural or in- nate juices of thofe Vegetables, in this they were all empty, like thol« o£ Vegetables chart d'-y but with this difierence, that they feem’d much larger then I have feen any in Char-coals ^ nay, even then thofe of Coals made of great blocks of Timber, which are commonly call’d Old-coals.
The reafbn of which difference may probably be, that the charring of Vegetables, being an operation quickly perform’d, and whileft the Wood is fappy, the more fblid parts may more eafily fhrink together, and con- traft the pores or interfitia between them, then in the rotten Wood, where that natural juice feems onely to be wafh’d away by advefttitiossf or unnatural moifture 5 and fb though the natural juice be wafted from between the firm parts, yet thofe parts are kept afunder by the adventi- tious moyftures, and fo by degrees fettled in thofe pofrures.
And this I likewife found in the petrify’ d Wood, that the pores were fbmewat bigger then thofe of Charcoal^ each pore being neer upon half as bigg again, but they did not bear that difproportion which is expreft in the tenth Scheme^ between the fmall fpecks or pores in the firft Fi- gure (which reprefenteth the pores of Coal or Wood charr’d) and the black fpots of the fecond Figure (which reprefent the like Microfeopical pores in the petrify’ d Wood) for thefe laft were drawn by a Microfeope that magnify’d the ob jedl above fix times more in Diameter then the Micre^ fcope by which thofe pores of Coal were obferv’d.
Now, though they were a little bigger, yet did they keep the exadt figure and order of the pores of Coals and of rotten Wood, which laft alfb were much of the fame cize.
The other Obfervations on petrify' d fubftance, that a while fince,
by the appointment of the Royal Society^ I made, and prefented to them an account of^ were thefe that follow, which, had the honour done them
Q_2 by
Micrographia.
by the moft accomplifh’d Mr. Evelin^ my highly honour’d friend, to be inferred and publiftied among thofe excellent Obfervations wherewith his Sylva is replenilh’d^ and would therefore have been here omitted, had not the Figure of them, as they appear’d through the il^Hcrofiopg been ^ before that engraven.
This Petriffd fubftance rcfembled Wood, in that
Firft, all the parts of it feem’d not at all dijlocated^ or alter’d from their natural Pofition, whil’ft they were Wood, but the whole piece re- tain’d the exad (hape of Wood, having many of the confpicuous pores 1 of wood ftili remaining pores, and (hewing a manifeft difference vifible enough between the grain of the Wood and that of the bark, efpecially when any lide of it was cut finooth and polite 5 for then it appear’d to have a very lovely grain, like that of feme curious clofe Wood.
Next (it refcmbled Wood) in that all the (mailer and (if I may (b call thofe which are onely vilible with a good magnifying Glafs) Microfeopt- cal pores of it appear (both when the fubftance is cut and polilh’d tranf iverjly and parallel to the pores of it) perfectly like the Microfiopical ^ovts offeveral kinds of Wood, elpecially like and equal to thofe of feveral forts of rotten Wood which I ha ve fince obferv’d, retaining both the lhape,po(itionand magnitude of fuch pores. It was difteringfrom Wood : Fiife, in weighty being to common water as 35 to i. whereas there are few of our EngUJh Woods, that when very dry are found to be full as heavie as water.
Secondly, in hardnef, being very neer as hard as a Flint 5 and in feme places of it alfo refembling the grain of a Flint: and, like it, it would j very readily cut Glafs, and would not without difficulty, efpecially in fome parts of it, be ferateh’d by a black hard Flint : It would alfo as rea- dily ftrike fire againft a Steel, or againft a Flint, as any common Flint.
Thirdly, in the clofettef oi it, for though all the Microfcopical pores of this petriffd fubftance were very confpicuous in one pofition ,yet by al- tering that pofition of the polifh’d furface to the light, it was alfo mani- feft:, that thofe pores appear’d darker then the reft of the body, onely becaufe they were fill’d up with a more dufkie fubftance, and not be- caufe they were hollow.
Fourthly, in its incombnfiibknef^ in that it would not burn in the fire 5 I
nay,though I kept it a good while red-hot in the flame of a Lamp, made very intenfe by the blaft of a (mail Pipe, and a large Charcoal, yet it feem’d not at all to have diminifh’d its extenfion 5 but only I found it to have chang’d its colour, and to appear of a more dark and dufkie brown colour f nor could I perceive that thofe parts which feem’d to have been Wood at firft, were any thing wafted, but the parts appear’d as folid and clofe as before. It was further obfervable alfo, that as it did not confome like Wood, fo neither did it crack and flie like a Flint, or fuch like hard Stone, nor was it long before it appear’d red-hot.
Fifthly, in its dijjelabknef j for putting fome drops of diftill’d Vinegar upon the Stone, I found it prefently to yield very many Bubbles, juft like thofe which may be obferv’d in fpirit of Vinegar when it corrodes corals^
though
M ! c R O G R A P H I A*
though perhaps many of thofe fmall Bubbles might proceed from Ibm^ imall parcels of Air which were driven out of the pores of this j’elr^W (ubftance by the infinuating liquid I v-v v
Sixthly, in its ngidfzefs and friabihtjf^ being not 06* all fle5?ibJe;but brittle like a Flint, infomuch that I could with one khock.of aHanmieS break off a piece of it, and with a few more, reduce ihat in&o.a pretty, finepowden ^ ''rioS-. ,1 h. »
Seventhly, it Teem’d allb very differing from.Woodto the ?»^morc cold then Woodufually does, and much likfj other elpTe ftOnes and Minerals. ’ *
The Reafons of all which Vh^nomem feeni to b©, • [jwXh g.; ' That thh petrify’d Wood having lain in feme place where h w'asrwel) Coak'd withpetrifjiwg water (that is., fueb a water ;as;i& well with ftony and earthy particles) did by degree? Teparate,either.by..fei'n* ing and 0tration^ or perhaps,by precipHatioft^ cohefionQt dance of Tfony particles from the permeating watetj which. fton,y pat’* tielesjbeing by means of the fluid vehicle convey d^not ondy into the^/?r trpfcppical pores, and fo perfeftly hoping them up, but al(b into: the' poj^es or mterfi/tid^which may, perhaps, be even in the texture or. ^ch^miijyfe of that part of the Wood, which, through the appears moft:
lid, do thereby To augment the weight of the Wood.,, as to fnakci®’ above three times heavier then water^ and perhap.s, fix times as heavie as itiwa$ when Wood. i,/; . : I
Next, they thereby fo lock up and fetter the paris of the Woodytte the fire cannot eafily make them file away, but the affioa .e^ tl^Sxb upon them isonely able to char thoTc parts, as it were, like a . piece of Wood^^f it be clos’d very faft up in Clay,and kept a good while red-hot fo^tbe fire^ will by the heat of the fire be chart’d and not conTum’d',.which iWyiperi^ haps, alTo be fomewhat of the caufe, why the petrify' appear’d of a dark brown colour after it had been burnt. ■ , :
By this intrufion of th^ petrifying particles, this Tubfiance alfo becomes hard and friable for the fmaJIer pores of the Wood being perfefHy wedg’d, and ftuft up with thofe ftony particles, the fin all parts of .the Wood have no places or pores into which they may fiide upon bendings land confoquently little or no flexion or yielding at all can be caus’d in fnch a fiibftance.
The remaining particles likewife of the Wood among the ftony par- deles, may keep them from cracking and flying when put into the fire, as they are very apt to do in a Flint.
Nor is Wood the onely Tubftance that may by this kind of iff tim be chang’d into ftone 5 for I my felf have feeo and examin’d very fBairy kinds of Tubftances, and among very credible Authours, we may meet with Hiftories of foch Metamorphofes wrought almoft on all kind of fijbftances, both Vegetable and Ammal^ which Hiftodes, it is not my bufineft at preTent, either to relate, or epitomife^ but only to let down feme Obforvation I lately made on feVeral kindof/>^/r7^’d Shels, found about Kemjham^ which lies within four or five miles of BrifiofyMf^aio commonly call’d Serpentine-jiones. Exami^
D M I CROGRAPHIA.
Examining feveral of thcfe very curioufly figur’d bodies (which are commonly thought to be Stones form’d by feme extraordinary Plajiic^ virtue latent in the Earth it felf ) I took notice of thefe particulars :
Firftj that thefe figured bodies, or ftoncs, were of very differing fub- ftances, as to hardnefs : fome of Clay, fome Marie, fome foft Stone, al- moft of the hardnefs of thofe foft ftoncs which Mafons call Fire-ftone, others as hard as Portland ftone, others as hard as Marble, and fome as hard a a Flint or Cryftal.
Next, they were of very differing fubftances as to tranfparency and colour ^ fome white, fome almoft black, fome brown, fome Metalline, or like Marchafites^ fome tranfparent like white Marble, others like flaw’d Cryftal,fome gray, fome of divers colours , fome radiated like thefe long petrify d drops ^ which are commonly found at the Veak^^ and in other jithterraneons caverns^ which have a kind of pith in the middle.
'fhirdly, that they were very different as to the manner of their out- ward figuration 5 for fome of them feem’d to have been the fubftance that had fill’d the Shell of fome kind of Shcl-fifh ^ others, to have been the fubftance that had contain’d or enwrapp’d one of thefe Shels,on both which,the perfed impreffion either of the infide or outfide of fiich Shells feem’d to be left, but for the moft part, thofo impreffions feem’d to be made by an imperfed or broken Shell, the great end or mouth of the Shell being always wanting, and oftentimes the little end, and fometimes half^ and in fome there were impreffions, juft as if there had been holes broken in the figurating, imprinting or moulding Shell 5 fome of them feem’d to be made by fuch a Shell very much brufed or flaw’d, infomuch that one would verily have thought that very figur’d ftone had been broken or brufed whilft a gelly, as 'twere, and fo hardned, but within in the grain of the ftone, there appear’d not the leaft fign of any foch brufo or breaking, but onely on the very uttermoft fuperficics.
Fourthly, they were very different,as to their outward coverings fome having the perfed Shell, both in figure, colour, and fubftance, fticking on upon its furface, and adhering to it, but might very eafily be fepa- rated from it, and like other common Cockje or Scolopf})eIs^ which fome of them moft accurately refembled,were very diftoluble in common Vinegary others of them,efpecially thofo Serpentine^ or Helical Jiones were cover'd or retained the fhining or Pearl-colour’d fubftance of the infide of a Shel, which fubftance, on fome parts , of them, was exceeding thin, and might very eafily be rubbed off^ on other parts it was pretty thick, and re- tained a white coat, or flaky fubftance on the top, juft like the outfides of fuch Shells^ fome of them had very large pieces of the Shell very plainly fticking on to them, which were eafily to be broken or flaked on by degrees : they likewife, fome of them retain’d all along the fiirface of them very pretty kind of juturesy fuch as are obforv’d in the fkulls of fo- vcral kinds of living creatures, which futures were moft curioufly fhap’d in the manner of leaves, and every one ofthem in the fame Shell, exadly one like another, which I was able to difeover plainly enough with my naked eye, but more pcrfedly and diftindjy with my Mkrofeope 5 all
thefe
M I C R d G R A P H I Ai
tliefe jutures^ by breaking fome of thele ftonesj fotmd to be the termihi^ . or boundings of certain diaphragms. ot partitions^ which feem’d to divide ; the cavity of the Shell into a multitude of very proportionate and regu- lar cells or caverns^ thefc Diaphragms.^ in many ofthem, I found very per- fed: and compleat, of a very diftind fubftance from that which fill’d the I' cavities, and exadly of the fame kind with that which covered the out- ; fide, being for the moft part whitilh, or mother-of-pearl colour’d.
As for the cavities between thole Diaphragms^ I found fome of tfiem fill’d with Marie, and others withfeveral kinds of ftones, others, for the ^ moft part hollow, onely the whole cavity was ufually covered over I with a kind of tartar eons petrify d fubftance, which ftuck about the fides^ I and was there (hot into very curious regular Figures, juft as Tartar [ other diftblv’d Salts are obferv’d to ftick and cryfaUi%& about the fides of I the containing Veftels^ or like thole little which I before ob-
ferved to have covered the vaulted cavity of a Flint , others liad thele cavities all lin’d with a kind of metalline or marcha(lte-likg fiibftancea which with a Microjeope I could as plainly lee moft curioully and regu- larly figured, as I had done thole in a Flint.
From all which, and feverai other particulars which I obferv’d, I can- not but think, that all thefe, and moft other kinds of ftony bodies which ! are found thus ftrangely figured, do owe their formation and figuration, not to any kind of Flafick^ virtue inherent in the earth, but to the Shells of certain Shel-fifties, which, either by fome Deluge, Inundation, Earth- <]uake,or fomefuch other means, came to be thrown to that place, and there to be fill’d with fome kind of Mudd or Clay, or petrifying Water, or Ibme other fubftance, which in trad of time has been fettled toge- ther and hardned in thole Ihelly moulds into thole lhaped fubftanees we now find them 5 that the great and thin end of thele Shells by that Earth- quake, or what ever other extraordinay caule it was that brought them thither, was broken off, and that many others were otherwife brol^en, bruiled and disfigured 5 that thele Shells wfoich are thus Jpirallied and fe- parated with Diaphragmes^were fome kind of Nautili or Porcelane fells 3 and that others were fhells of Cockles^MufclesTerirvincles^ Scolopsfyic. of various forts 3 that thefe Shells in many, from the particular nature of the containing or enclos’d Earth, or fome other caufo, have in trad of time rotted and mouldred away, and onely left their impreffions, both on the containing and contained fubftanees , and fo left them pretty loofe one within another, fo that they may be eafily feparated by a knock or two of a Hammer, l hat others of thele Shells, according to the nature of the lubftanccs adjacent to them, have, by a long continuance in that pofture, been petriffd and turn’d into the nature of ftone, juft as I even now obforv’d feverai forts of Wood to be* That oftentimes the Shell may be found with one kind of fubftance within, and quite another without, having, perhaps, been fill’d in one place, and afterwards tranfla- ted to another, which I have very frequently observ’d in Cockle:, Mufile^ Veriwincle^ and other Ihells, which I have found by the Sea fide. Nay, further, that fome parts of the fame Shell may be fill’d in, one place, and
fome
II2 Micrographia.
fo«ie other caverns in another, and others in a third, or a fourth, of a fifth place, for fo many differing fubftances have I found in one of thefe trifyd Shells,and perhaps all thefe differing from the encompafling earth or ftonc ^ the means how all which varieties may be caus’d, I think, will not be difficult to conceive, to any one that has taken notice of thole Shells, which are commonly found on the Sea Ihore ; And he that ftiall throughly examine leveral kinds of fuch curioully form’d ftones,wilI (I am very apt to think) find reafon to fuppole their generation or forma- tion to be afcribable to fome fuch accidents as I have mention’d, and not to any Plajiick^ virtue : For it feems to me quite contrary to the in- finite prudence of Nature, which is oblcrvable in all its works and pro- dudions, to defign every thing to a determinate end, and for the attain- ing of that end, makes ule of liich ways as are (as farr as the knowledge of man has yet been able to reach) altogether conlbnant, and moft agreeable to man’s realbn, and of no way or means that docs contradid, or is contrary to humane Ratiocination 5 whence it has a long time been a general oblervation and maxime, that Nature does mthiug in vain 5 It Icems, I lay, contrary to that great Wifdom of Nature, that thele prettily Ihap’d bodies Ihould have all thofe curious Figures and contrivances (which many of them are adorn’d and contriv’d with) generated or wrought by a Plajiick^ virtue^ for no higher end 'then onely to exhibite filch a form 5 which he that lhall throughly conlidcr all the circumftances of filch kind of Figur’d bodies, will, I think, have great realbn to be- lieve, though, I confels, one cannot prelently be able to find out what Nature’s defigns are. It were therefore very defirable, that a good col- ledion of luch kind of figur’d ftones were colleded ^ and as many par- ticulars, circumftances, and informations colleded with them as could be obtained, that from fuch a Hiftory of Oblervations well rang’d, ex- amin’d and digefted, the true original or produdion of all thole kinds of ftones might be perfedly and liirely known 5 fuch as are Jhundcr- Jiones^ Lapides Stellar es^ Lapides Judaici^znd multitudes of other, where- of mention is made in Aldrovandus IVormius^ and other Writers of Minerals.
Oblcrv. X V 1 1 J, Of the Schcmatifme or Texture (f Cork, and of the Cells and Fores of fome other fuch frothy Bodies,
I Took a good clear piece of Cork, and with a Pen-knife lharpen’d as keen as a Razor, I cut a piece of it off, and thereby left thelurface of it exceeding fmooth, then examining it very diligently with a Micro- JeopCj me thought I could perceive it to appear a little porous, but I could not lb plainly diftinguilh them, as to before that they were pores, much left what Figure they were of: But judging from the lightnefi and yielding quality of the Cork, that certainly the texture could not be lb
curious.
Migrographia.
curious, but that poffibly, if I could ufe fortie further diligence, I might find it to be dilcernable with a Mkrofcope^ I with the fame fharp Pen- knife, cut off from the former frUooth furface an exceeding thin piece of it, and placing it on a black objedl: Plate, bccaule it was it felf a white body, and cafting the light on it with a deep plano-convex Glafs^ I could exceeding plainly perceive it to be all perforated and porous,much like a Honey-comb,but that the pores of it were not regular, yet it was not unlike a Honey-comb in thefe particulars.
Firff, in that it had a very little folid fubftance, in comparilbh of the empty cavity that was contain'd between, as does more raanifeftly appear by the Figure A and B of the X I. Scheme^ for the Interjiitia^ or walls (as I may fo call them) or partitions of thofe pores were ncer as thin in proportion to their pores, as thole thin films of Wax in a Honey-comb (which enclofe and conftitute the Jexangnlar cells') are to theirs.
Next, in that thele pores, or cells, were not very deep, but confided ofa great many little Boxes, feparated out of one continued long pore, by certain Diaphragms^ as is vilible by the Figure B, which rcprefents a fight of thofe pores fplitthe long- ways.
I no looner dilcern’d thefe ( which were indeed the firft microfiopkal pores I ever law, and perhaps, that were ever feen, for I had not met with any Writer or Perlbn, that had made any mention of them before this) but me thought I had with the difeovery of them, prefently hinted to me the true and intelligible realbn of all the rh<fnomena of Cork , As,
Firft, if I enquir’d why it was lb exceeding light a body? my Micro-^ jeope could prefently inform me that here was the feme realbn evident that there is found for the lightnefs of froth, an empty Honey-comb, Wool^ a Spunge, a Pumice-ftone, or the like 5 namely, a very fmall quantity of a fblid body, extended into exceeding large dimenfions.
Next, it feem’d nothing more difficult to give an intelligible reafon^ why Cork is a body lb very unapt to fuck and drink in Water, and con- fequently preferves it felf^ floating on the top of Water, though left on it never lb long : and why it is able to ftop and hold air in a Bottle,though it be there very much condens’d and confequently prefles very ftrongly to get a paflage out, without fuflering the leaft: bubble to pafs through its mbftance. For, as to the firft, fince our Microfeope informs us that the fubftance of Cork is altogether fill’d with Air, and that that Air is per- fe(ftly enclofed in little Boxes or Cells diftind from one another. It feems very plain, why neither the Water, nor any other Air can eafily infinu-* ate it felf into them, fince there is already within theiti an intus exijiens, and confequently, why the pieces of Cork become lb good floats for Nets, and floppies for Viols, or other clofe Veffels.
And thirdly, if we enquire why Cork has fuch a fpringinels and Iwel- ling nature whem comprels’d ? and how it comes to fiifl[cr lb great a com- preffion, or feeraing penetration of dimenfions, fb as to be made a fiib- ftance asheavie again and more, bulk for bulk, as it was before compref fion,andyet lufler’d to return, is found to extend it felf again into the feme Ipace ? Our Microfeope will eafily inform us, that the whole mals
R. confifts
^ M ICROGRAPHIA.
confifts of an infinite company of fmall Boxes or Bladders of Air, which is a fubftance of a fpringy naturCj and that will fuffer a confiderable con- dcnfation (as I have feveral times found by divers trials, by whith I have moft evidently condens’d it into lefi then a twentieth part of its ufual di- mcnfions neer the Earth, and that with no other ftrength then that of my hands without any kind of forcing Engine,fuch as Racks, Leavers, Wheels, Pullies, or the like, but this onely by and by) and befides, it feems very probable that thofe very films or fides of the pores,have in them a fpring- ing quality, as almoft all other kind of Vegetable fubfiances have, fo as to help to reftore themfelves to their former pofition.
And could we fo eafily and certainly discover the Schematifme and texture even of thele films,and of le veral other bodies, as we can thele of Cork 5 there leems no probable reafon to the contrary, but that we might as readily render the true reafon of all their Vh^nomena x, as namely, what were the caufe of the fpringinefs, and toughnefs of fbme, both as to their flexibility and reftitution. What, of the friability or brittlenefs of fome others, and the like 5 but till fuch time as our Mkrojeope^ or fbme other meanSjenable us to difeover the true Schematijm and Texture of all kinds of bodies, we muff grope, as it were, in the dark, and onely ghels at the true reafbns of things by fimilitudes and comparifons.
But, to return to our Obfervation. I told feveral lines of thele pores, and found that there were ufually about threefcore of thefe Imall Cells placed end-ways in the eighteenth part of an Inch in length, whence I concluded there muff be neer eleven hundred of them, or fbmewhat more then a thouland in the length of an Inch, and therefore in a fquare Inch above a Million, or ii66400.and in a Cubick Inch,above twelve hundred Millions, or 1 2 5 97 1 2000. a thing almoft incredible, did not our Microjeope afliire us of it by ocular demonftration ^ nay, did it not difeo- ver to us the pores of a body, which were they diaphragm d^Wkt thofe of Cork, would afford us in one Cubick Inch, more then ten times as many little Cells, as is evident in feveral charr’d Vegetables^ fo prodigioufly curious are the works of Nature, that even thefe confpicuous pores of bodies, which feem to be the channels or pipes through which the Snccus nutritius^ or natural juices of Vegetables are convey’d, and feem to cor- refpondto the veins, arteries and other Veflels in fenfible creatures, that thefe pores I fay, which feem to be the Veflels of nutrition to the vaflefl: body in the World, are yet fb exceeding fmall, that the Atoms which Epi-r curushneyd would go neer to prove too bigg to enter them, much more to conflitute a fluid body in them. And how infinitely fmaller then muff: be the Veflels of a Mite, or the pores of one of thofe little Vegetables I have difeovered to grow on theback-fide of aRofe-leaf, andfhall anon more fully deferibe, whofe bulk is many millions of times lefs then the bulk of the fmall fhrub it grows on, and even that fhrub, many millions of times lefs in bulk then feveral trees (that have heretofore grown in Evglandy and are this day flourifhing in other hotter Climates, as we are very cre-^ dibly inform’d) if at leaft the pores of this fmall Vegetable fhould keep any fuch proportion to the body of it , as we have found thefe pores
of
MlC R O GR A P H i Ai Il5
of Other Vegetables to do to their bulk. But of thefe pores I have laid more elfewhere.
To proceed then, Cork feems to be by the trahlverfe conflitution of the pores, a kind of Fatigue or Muflirome, for the pores lie like fo many Rays tending from the center, orpithof the tree, outwards 5 fb that if you cut oft a piece from a board of Cork tranfverlly, to the fiat of it^ you will, as it were, fplit the pores, and they will appear juft as they are exprefs’d in the Figure B of the X I. Scheme. But if you (have off a very thin piece from this board, parallel to the plain of it,, you will cut all the pores tranlverlly, and they will appear almbft as they are exprels’d in the Figure A, lave onely the Iblid Interjiitia will not appear lb thick as they are there reprefented.
So that Cork feems to fuck its nourilhment froiii the fubjacent bark of the Tree immediately, and to be a kind of excrefcence, or a lubftance diftirid: from the fubftances of the entire Tree, fomething analogus to the Mulhrome, or Mofs on other Trees, or to the hairs on Animak. And having enquir’d into the Hiftory of Cork, I find it reckoned as an excrelcency of the bark of a certain Tree, which is diftind from the two barks that lie within it, which are common alfo to other trees , That tis fome time before the Cork that covers the young and tender Iprouts comes to be dilcernable^ That it cracks, tlaws,and cleaves into many great chaps, the bark underneath remaining entire. That it may beleparatcd and remov’d from the Tree, and yet the two under-barks (liich as arc allb common to that with other Trees) not at all injur’d, but rather helped and freed from an external injury. Thus Jo^Jioms in Dendrologiay fpeaking de Subere^ fays. Arbor eji proceru. Lignum eji robujinm^ dempto cortice in aquk non fluitat^ Cortice in orbem detraSto juvatur^ crafeefeens enimprajiringit jirangulat^ infra triennium iterum repletur : Candexubi adolefcit crajjiis^ cortex Juperior denfus carnojus^duos digitos crajjus^jeaber^ rimojhs^ qui niji detrahatur dehifeit^ alioque jubnafeente expeUitur^ intc*
rior qui JubeJi novellus ita rubet ut arbor minio piBa videatur. Which Hiftories,if well confider’d, and the tree, fubftance, and manner of grow- ing, if well examin’d, would, lam very apt to believe, much confirm this my conjecture about the origination of Cork.
Nor is this kind of Texture peculiar to Cork onely , for upon exami- nation with my Microfeope, I have found that the pith of an Elder, or al- molt any other Tree, the inner pulp or pith of the Cany hollow ftalksof feveral other Vegetables : as of Fennel, Garrets, Daucus, Bur-docks, Tealels, Fcarn, fome kinds of Reeds, ^c. have much fuch a kind of Schematifme^ as I have lately Ihewn that of Cork, lave onely that here the pores are rang’d the long-ways, or the fame ways with the length of the Cane,whereas in Cork they are tranfverle.
The pith alfo that fills that part of the ftalk of a Feather that is above the Quil, has much foch a kind of texture, lave ortely that which way fo- ever I let this light lubftance, the pores feem’d to be cut tranlVerfly 3 fo that I ghefs this pith which fills the Feather, not td confift of abundance of long pores feparated with Diaphragms, as Cork does, but to be a kind
R 2 of
J Micrographia.
of fblid or hardncd frothjor a cetigeries of very Imall bubbles confolidated in that fornijinto a pretty ftiffas well as tough concretejand that each Ca- vern, Bubble, or Cell, is diftindly leparate from any of the reft, without any kind of hole in the encompafling films, fo that I could no more blow through a piece of this kinde of lubftance,then I could through a piece of Cork, or the found pith of an Elder.
But though I could not with my Microjcope^ nor with my breath, nor any other way I have yet try’d, difoover a pallage out of one of thofo cavities into another, yet I cannot thence conclude, that therefore there are none fiich, by which the Succus "or appropriate juices of Ve-
getables, may pais through them 5 for, in fcveral of thofe Vegetables, whil’ft green, I have with my Mkrofeope^ plainly enough difeover’d thefe Cells or Poles fill'd with juices, and by degrees (wearing them out ; as I have alfo obforved in green Wood all thofe long Microfcopical pores which appear in Charcoal perfedly empty of any thing but Air.
Now, though I have with great diligence endeavoured to find whe- ther there be any iiich thing in thofo Microfeopical pores of Wood or Piths, as the Valves in the heart,veins,and other paflages of Animals,that open 'and give paflage to the contain'd fluid juices one way, and ihut themfolves,and impede the paflage of fuch liquors back again,yet have I not hitherto been able to (ay any thing pofitivein it 3 though, me thinks, it foems very probable,that Nature has in thefo paflages,as well as in thofo of Animal bodies,very many appropriated Inftruments and contrivances, whereby to bring her defigns and end to pais, which 'tis not improbable, but that fome diligent Obforver, if help’d with better Microfeopes^ may in time detedt.
And that this may be fo, foems with great probability to be argued from the ftrange Phammena of fonfitive Plants, wherein Nature foems to perform feveral Animal aftions with the fame Schematifm or Orgini^a'- tion that is common to all Vegetables, as may appear by fome no left inftrudtive then curious Obforvations that were made by divers Emi- nent Members of the Royal Society on fome of thcle kind of Plants, where- of an account was delivered in to them by the moft Ingenious and Excel- lent Phyjician^ Dodior Clarke, which, having that liberty granted me by that moft Illuftrious Society, I have hereunto adjoyn'd.
Obfervations on the Humble and Senfible Plants in M' Chiffin’i Garden in Saint ]zmes"s Park-i ^^de Auguft the 9'**’
Prefent^ the Lord Brouncker^ Sr. Robert Moray^ Dr. Wilkins, Mr. Evelin, E>r,HenJhavp, andP^r, Clarkj
There are four Plants, two of which are little fhrub Plants, with a little (hort flock, about an Inch above the ground, from whence are fpread feveral fticky branches, round, ftreight, and
fmooth,
M I C R OG R A P H 1 A. II7
fmootli in the diftancea between the Sprouts, but juft under the Sprouts there are two ftiarp thorny prickles, broad in the let- ting on,‘ a^ in the Bramble, one juft under the: Sprout, the other on the oppofite fide of the branch. . . .
The diftances betwixt the Sprouts are uftially forhething ^ scs more then an Inch, and many upon a Branchy according to its »• length, atid they grew fo, that if the lower Sprout be on the left fide of the Branch, the next above is on the right, and^fo to the end, not Iprouting by pairs. As • . r p i '
At the end of each Sprout are generally four fprigs, two at the Extremity, and one on each fide, juft under it. At theifirft fprouting of thefe from the Branch to the Sprig where the leaves grow, they are full of little fhort white hairs, which wear off as -the leaves grow, and then they are fmooth as the Branch.^ rlj r o Upon each of thefe fprigs, are, for the moft'part, eleven pair of leaves, neatly fa into the uppermoft part’of the little fprig, exaffly one againft another,, as it were in little articu/atms^fuch as Anatomifts call Enarthrcfis^ where the round head of a Bone is received into another fitted for its motion ; and ftandiiig very fitly to fhut themfolves and touch, the pairs juft above them clofing fomewhat upon them, as in the (hut fprig ^ifo is the little round Pedunculus of this leaf fitted into a little cavity of the fprig, vifible to the eye in a fprig new pluck’d, or in a fprig withered on the Branch, from which the leaves eafily fall by touching.
The leaf being almoft an oblong fqnare, and let into the Fe^ dunculus^ 2.1 ont of the lower corners, receiveth from that not onely a as I may call it, which, paffing through the leaf^ divides it fo length-ways that the outer-fide is broader then the inner next the fprig, but little fibres paffing obliquely towards the oppofite broader fide, feem to make it here a little mufcular, and fitted to move the whole leaf^ which, tc^ether with the whole fprig, are fa full with little fhort whitifh hairs.
One
ii8
Micrographi a.
One of thefe Plants, whofe branch feem’d to be older and inore grown then the other, onely the tender Sprouts of it, after the leaves are (hut, fall and hang down ; of the other, the whole branches fall to the ground, if the Sun fhine very warm,upcn the firft taking ofFtheGlals, which I therefore call the humble Plant.
The other two, which do never fall, nor do any of their branches flagg and hang down, fhut not their leaves, but upon fomewhat a hard ftrokc ; the ftalks fcem to grow up from a root, and appear more herbaceous^ they are round and fmooth, without any prickle, the Sprouts from them have fevcral pairs of fprigs, with much lefs leaves then the other on them, and have on each fprig generally feventeen pair.
> Upon touching any of the fprigs with leaves on, all the leaves on thatTprig contradling themfelves by pairs, joyned their up- per fuperficies clofe together.
Upon the dropping a drop of Aqua forth on the fprig be- twixt the leaves, f f all the leaves above fhut prefcntly, thole below by pairs fucccffivcly after, and .by the lower leaves of the other branches, / /, kk-, &c. and fo every pair fucceffively, with fome little diftance of time betwixt, to the top of each fprig, and fo they continu’d fhut all the time we were there. But I re- turning the next day, and feveral days lince, found all the leaves dilated again on two of the fprigs ; but from ff where the Aqua forth had dropped upwards, dead and withered ; but thofc be- low on the fame fprig, green, and doling upon the touch, and are fo at this day, Augufl 14,
With a pair of Scifl'ers, as fuddenly as it could be done, one of the leaves b b was clipped off in the middle,upon which that pair, and the pair above, clofcd prefcntly, after a little interval, d then e e, and fo the reft of the pairs, to the bottom of the fprig, and then the motion began in the lower pairs, / /, on the other fprigs, and fo fhut them by pairs upwards, though not with fuch diftind diftances.
I
Under
M
[CROGRAPHIA
Under a pretty lai^e branch with its fprigs on, there lying a large Shell betwixt two and three Inches below it, there was rubbed on a ftrong fented oyi, after a little time all the leaves on that fprig were fbut, and fo they continued all the time, of our ftay there, but at my rcturne the next day, 1 found the pohtiort of the Shell alter’d, and the leaves expanded as before, and doling upon the touch.
Upon the application of'theSun-bcams by a Burning-glafs, the more humble Plant fell, the other fhut their leavesi
We could not fo apply the fmoak of Sulfher^ as to have any- vilible- effeft from that, at two or three times trial ; but on ano* ther trial,rhe fmoak touching the leaves, it fucceeded.
The humble Plant fell upon taking off the Glafs wlaerewith it was covered.
Cutting off one of the little Sprouts, two or three drbps of li- quor were thruft out of the part from whence that was cm’, very deer, and pellucid, of a bright greenifh colour, tafting at firft t little bitt'erifh,but after leaving a licorifh-like tafte in my mouth,
Since,going two or three times when it -was cold,! took the Glafles from the more humble Plant^d^nd it did not fall as former- ly, but'fhuC its leaves onely* But coming afterwards, when the Sun fhone very warm, as foon it v/as taken off," li fell as before.' f
: Since I pluck'd off another fprig, whdfe leaves were all ihut,' and had been fo fbme cima,^ thinking to obferve the liquor ftiould €Oine from thatff had broken off, but finding none,^ thoi^h Ivkh prefling^to come, I, dexteroufly as I could, pull'd off one whole leaves were expandedfand then had upon the fh lif- ting (ffthe leaves, a httle of the haention’d liquor, from the end ofthe fprig 1 had bi’c^en from the Plant* And this twice fuc- ceflively, as often almoft as 1 durft rob the Plant. ■ ■ '
But my curiolity carrying me yet further, I cut off one of the harder branches of the ftronger Plant, and there came ofthe
liquor,^
120 Micrographia.
liquor, both from that I had cut, and that I had cut it from, without preflure.
Which made me think, that the motion of this Plant upon touching, might be from this, that there being a conftant courfe betwixt every part of this Plant and its root, either by a cir- culation of this liquor,or a conftant prefling of the fubtiler parts of it to every extremity of the Plant. Upon every preflure, from whatfoever it proceeds, greater then that which keeps’^it up, the fubtile parts of this liquor are thruft downwards, towards \xz ar- ticulations of the leaves, where, not having room prcfently to get into the fprig,the little round pedunculus^ from whence the Spine and thole oblique Fibres I mention’d rife, being dilated, the Spine and Fibres (being continued from it} muft be conrraded and fhorrned, and fo draw the leaf upwards to joyn with its fel- low in the fame condition with it fclf^ where, being clofed,thcy are held together by the implications of the little whitifh hair, as well as by the ftill retreating liquor, which diftending the Fibres that are continued lower to the branch and root, fhorten them above ; and when the liquor is fo much forced from the Sprout, whole Fibres are yet tender, and not able to fupport themfelves, but by that tenfnefs which the liquor filling tlieir inter fiices gives them, the Sprout hangs and flags.
But, perhaps, he that had the ability and leifurc to give you the exad Anatomy of this pretty Plant, to fhew you its Fibres, and vifible Canales^ through which this fine liquor circulateth, or is moved, and had the faculty of better and more, copioufly cxprefling his Obfervations and conceptions, fuch a one would ealily from the motion of this liquor, folve all the Phdinomenai and would not fear to affirm, that it is no obfeure fenfation this Plant hath. But I have faid too much, I humbly fubmk^ and am ready to ftand correded.
I have not yet made lb full and latisfaftory Oblervations as I deflre on this Plant, which leeras to be a Subjed that will afibrd abundance of
information.
MlCROGRAPHlAi I2I
information. Ent as fan as 1 have had opportunity to examine itj have difcovered with my Microjcope very curious ftrudures and contrivances, but defigning much more accurate examinations and trials^both with my Mtcrofcope^ and otherwife, as foon as the feafon will permit, I (hall not till jthen add anything of what I have already taken notice of^ but as fan as I have yet oblerv’d,! judge the motion of it to proceed from caufes very differing from thofe by which Cut-ftrings^or Lute-ftrings,the beard of a wilde Oat^ or the beard of the Seeds of Geramum^ Mojcatum^ or Mnsk^. graJ^SLud other of kinds of Cr^/?f/4i//,move themfelves. Of which I fhall add more in the lubfequent ObferVations on thofe bodies.
Obferv. XIX. Of a growing in the blighted or yellow f^eck^
oy'Damask-rofe-Ieaves, Bramble-leaves, and form other hind cf leaves,
T Have for feveral years together, in the Moneths oijnne^jnly^ Augnji^ and September (when any of the green leaves oiRofes begin to dry and grow yellow) obferv’d many of them, efpecially the leaves of the old Ihrubs of Damast^RoJes^ all befpecked with yellow iftains, and the under- fides juft againft them, to have little yellow hillocks of a gummous fub- ftance, and feveral of them to have fmall black fpots in the midft of thofe yellow ones, which, to the naked eye, appear'd no bigger then the point of a Pin, or the fmalleft black fpot or tittle of Ink one is able to make with a very fharp pointed Pen.
Examining thefe with a Microfcope^ I was able plainly to diftihguii"b,up and down the furface, feveral fmall yellow knobs, of a kind of yellowifh' red gummy flibftance, out of which I perceiv’d there fprung multitudes of little cafes or black bodies like Seed-cods, and thofe of them that were quite without the hillock of Gumm, difclos’d themfelves to grow out of it with a fmall Straw-colour’d and tranfparent ftem, the which feed and ftcm appear’d very like thofe of common Mofs (which I elfc- wherc defcribe) but that they were abundantly left, many hundreds of them being not able to equalize one fingle feed Cod of Moft.
. 1 have often doubted whether they were the feed Cods of fome little Plant, or feme kind of fmall Buds, or the Eggs of feme very fmall Infed, they appear’d of a dark brownifh redj fbrrie almoft quite black, and of a Figure much refembling the feed-cod of Moft, but their ftalks on which they grew were of a very fine tranfparent fubftance, almoft like the ftalk of mould, but that they feem’d fbmewhat more yellow.
That which makes me to fuppofe them to be Vegetables, is for that! perceiv’d many of thofe hillocks bare or deftitute, as if thofe bodies lay yet cohceaI’d,as C. In others of them,they were juft fpringing out of their gummy hillocks, which all feem’d to (hoot direftly outwards, as at A. In Others, as at B, I found them juft gotten out, with very little or no ftalk,'
S ^nd
122
MiCR O GR AP H I A.
and the Cods of an indifferent cize^but in othcrs^as C, I found them begift to have little fhort ftalks, or ftems^ in others^ as D, thofe ftetnsWei*e grown bigger, and larger , and in others, as at E, F, H, I, K, L, &c. thofe ftems and Cods were grown a great deal bigger, and the ftalks were more bulky about the root, and very much taper'd towards the top, as at F and L is moft vifible.
I did not find that any of them had any feed in them, or that any of them were hollow, but as they grew bigger and bigger, I found thofe heads or Cods begin to turn their tops towards their roots, in the (atrio manner as I had obferv'd that of Mofs to do 5 fo that in all likelihood. Nature did intend in that pofture, what (he does in the like feed-cods of greater bulk, that is, that the leed, when ripe, (hould be Ihaken out and dilperfed at the end of it, as we find in Columbine Cods, and the like.
The whole Oval OOOO in thefecond Ftgurh of the i'i. sche>ftd reprefents a iinall part of a Rofe leaf, about the bignels of the little Oval in the hillock, C, marked with the Figure X. in which I have not par- ticularly obferv’d all the other forms of the furface of the Rofe-leai^ as being little to my prefent purpofe.
Now, if thefe Cods have a feed in them fo proportion’d to the Cod, as thofe of snd Carnations^ and Columbines^ and the like, how unima- ginably finall muft each of thofe feeds necelfarily be, for the whole length of one of the largeft of thofe Cods was not part of an Inch 3 fome not above , and therefore certainly, very many thoufand of them would be unable to make a bulk that fhould be vifible to the naked eye 3 and if each of thefe contain the Rudiments of a young Plant of the fame kind, what muft we fay of the pores and conffituent parts of that }
The generation of this Plant feems in part,afcribable to a kind of Mil^^ ikvp or £//^^^,whereby the parts of the leaves grow fcabby, or putrify’d, as it were, fo as that the moifture breaks out in little feabs or fpots, which, as I laid before, look like little knobs of ' a red gummous fubffance.
From this putrify ’d feabb breaks out this little Vegetable 3 which may be fomewhat like a Mould or Mof 3 and may have its equivocal genera- tion much after the fame manner as I have fuppofed Mofs or Mould to have, and to be a more fimple and uncompounded kind of vegetation, which is fet a moving by the putrifaSlive and fermentative heat, joyn’d with that of the ambient aerial, when (by the putrifadfion and decay of fome other parts of the vegetable, that for a while ftaid its progrels) it is unfetter’d and left at liberty to move in its former eourfe, but by reafon of its regulators^ moves and adis after quite another manner then it did when a coagent in the more compounded machine of the more perfedf Vegetable.
And from this very fame Principle, I imagine the Mifleto of Oaks, Thoms, Appletrecs, and other Trees, to have its original : It feldom or never growing on any of thofe Trees,till they begin to wax decrepid,and decay with age, and are pcftcr’d with many other infirmities.
Hither alfo may be referr’d thofe multitudes and varieties of Mujhroms^ fuch as thatjcall’d jfe»x-e4rx, all forts oigrajf smdgmn Mofles,&e. which
infeft
Micrograph i a.
infeft all kind of Trees3fhrubs5and the likejelpecially when they eome to any bignefs. And this we fee to be very much the method of Nature throughout its operations, putrifaBive Vegetables very oiten producing a Vegetable ofa much lefs compounded nature, and of a much inferiour tribe 5 and putrefaBive animal fubftances degenerating into fomekind of animal production of a much inferiour rank,and of a more fimple nature.
Thus we find the humours and fubfiances of the bodv,upon putrifaBi- on^to produce ftrange kinds of moving Vermine : the pntrifaBion of the Himes and juices of the Stomack and Cuts, produce Worms almoft like Earth-worms,the Wheals in childrens hands produce a little Worm,eaird a Wheal-vporm : The bloud and milk, and other humours, produce other kinds of Worms, atleaft, if we may believe what is deliver’d to us by very famous Authors though, I confefs, I have not yet been able to dif cover fuch my lelfi
And whereas it may feem ftrange that Vinegar^ Meal^ mufty Casks , are obferv’d to breed their differing kinds of InfeCts, or living creatures, whereas they being Vegetable fubftances, feem to be of an inferiour kind, and fo unable to produce a creature more noble, or of a. more com- pounded nature then they themfelves are of, and fo without fome con- current feminal principle, may be thought utterly unfit for fiichan ope- ration ^ I muft add, that we cannot prefently pofitively fay, there are no animal fubftances, either mediately, as by the foil or fatning of the Plant from whence they fprung,or more immcdiately,by thereal miixture orcompofitionof fuch fubftances, join’d with them 5 or perchante fome kind of Infeft, in fuch places where fuch kind of putrifywg ot fermenV ing bodies are, may, by a certain inftinCt of nature, eje<ft forae fort of fe^ minal principle, which cooperating with various kinds of pntrifyivg fub- ftances, may produce various kinds of Infeds,or Animate bodies ; For we find in moft forts of thole lower degrees of Animate bodies, that the pHtrifyitig fubftances on which thefe Eggs, Seeds, or feminal principles arccaft by the Infedc, become, as it were, the Matrices or Wombs^that conduce very much to their generation, and may perchance alfoto theit variation and alteration, much after the fame manner, as, by ftrange and unnatural copulations, feveral new kinds of Animals are produc’d, as Mules^ and the like, which are ufually call d Monftrous, becaufe a little unufual, though many of them have all their principal parts as perfectly fliap’d and adapted for their peculiar ufes, as any of the moft perfeft Animals. If therefore the putrifying body, on which any kind of feminal or vital principle chances to be caft. become fomewhat more then meet- ly a nurfing and foftering helper in the generation and produdfion of any kind of Animate body, the more neer it approaches the true nature of a Womb, the more power will it have on the by-blow it inclofes. But of this fomewhat more in the defoription oi the Water-gnat. Perhaps fome more accurate Enquiries and Obfervations about thefe matters might bring the Queftion to fome certainty, which would be of no fmall concern in Natural Philofophy. >
But that putrifying animal fubftances may produce animals of an inferior
S 2 kind^
T24
Micrographia.
kind, I fee not any fo very great a difficulty, but that one may, without much ablurdity,admit : For as there may be multitudes of contrivances that go to the making up of one compleat Animate body 5 fo,That Ibmc of coadjutors perfeft exiftence and life of it, may be vitiated, and the life of the whole deftroyed, and yet feveral of the confrituting contrivances remain intire,! cannot think it beyond imagination or poffibi- lity5 no more then that a like accidental procels,as I have elfwhere hinted, may allb be fuppofed to explicate the method of Nature in the Met amor- phojis of Plants. And though the difference between a Plant and an Ani- mal be very great, yet I have not hitherto met with any fo cogent an Ar- gument, as to make me pofitive in affirming thefe two to be altogether Heterogeneous of quite differing kinds of Nature: And befides^as there
are many Zoophyts^ and fenfitive Plants(divers of which I have feen, which are of a middle nature,and feem to be Natures tranfition from one degree to another, which may be obferv’d in all her other paffages, wherein fhe is very feldom obferv’d to leap from one ftep to another) fo have we,in ibme Authors, Inftancesof Plants turning into Animals, and Animals into Plants, and the like , and fome other very ftrange (bccaule unheeded) proceedings of Nature^ Ibmething of which kind may be met with, in the delcription of the Water-Gnat^ though it be not altogether fb direbt to the prelent purpole.
But to refer this Dilcourle of Animals to their proper places, I lhall add, that though one Ihould fuppole, or it fhould be prov’dby Obferva- tionSj that leveral of thele kinds of Plants are accidentally produc’d by a caliial putrifaBion^ I lee not any great reafon to queftion, but that, not- withftanding its own produftion was as ’twere cafual, yet it may germi-*- natc and produce feed, and by it propagate its own, that is, a new Species. For we do not know, but that the Omnipotent and All- wife Creator might as direftly defign the ftrufture of fuch a Vegetable, or fuch an Animal to be produc’d out of fuch or luch a putrifaBion or change of this or that body, towards the conffitution or ftrudlure of which, he knew it necelTary, or thought it fit to make it an ingredient 5 as that the digeftion or moderate heating of an Egg, either by the Female, or the Sun, or the heat of the Fire, or the like, fhould produce this or that Bird 5 or that VutrifaBive and warm fteams lhould,out of the blowings, as they call them, that is, the Eggs of a Flie, produce a living Magot, and that,by degrees, be turn’d into an Aurelia^ and that, by a longer and a propor- tion’d heat, be tranfmuted into a Fly. Nor need we therefore to fuppole it the more imperfed: in its kind, then the more compounded Vegetable or Animal of which it is a part , for he might as compleatiy furnilh it with all kinds of contrivances necellary for its own exiftenee, and the propagation of its own Species, and yet make it a part of a more com- pounded body : as a Clock-maker might make a Set of Chimes to be a part of a Clock, and yet, when the watch part orffriking part are taken away, and the hindrances of its motion remov’d, this chiming part may go as accurately, and ftrike its tunc as exadiy, as if it were ffill a part of the compounded Automaton, So, though the original caule, or
feminal
Micrographia^ I
feminal principle from which this minute Plant on Rofe leaves did fpringi were, before the corruption caus’d by the Mill-dew, a compguent part of the leaf on which it grew, and did ferve as a coagent in the produdli- on and conftitution of it, yet might it be fo confummate, as to produce a feed which might have a power of propagating the fame fpeciesdhe works of the Creator feeming of fech an excellency, that though they are unable to help to the perfedfing of the more compounded exiftencc of the greatet Plant or Animal,they may have notwithflanding an ability of ading (ingl;^? upon their own internal principle, fo as to produce a Vegetable body^ though of a lefs compounded nature, and to proceed fo farr in the me-^ thod of other Vegetables, as to bear flowers and feeds, which may be ca- pabale of propagating the like. So that the little cafes which appear tq grow on the top of the flender ftalks, may, for ought I know, thou^li I (hould fuppofe them to fpring from the perverting of the ufual courjfe of the parent Vegetable, contain a feed, which, being fcattef d on othef leaves of the fame Plant, may produce a Plant of much the feme kind.
Nor are Damafk-Rofe leaves the onely leaves that produce thefe kinds of Vegetable fproutings, for I have obferv’d themalfoin feveral other kinds of Rofe leaves, and on the leaves of feveral forts of Briers, and on Bramble leaves they are oftentimes to be found in very great duffers , fb that I have found in one cIufter,three,four, or five hundred of them, making a very confpicuous black ipot or feab on the back fide of the leaf.
Obferv. XX. Of blue Mould, and (f the fixfi Prmdfks of Vc4 getation arifmg from Putrefaftion,
THe Blue and White and feveral kinds of hairy mouldy fpots, which are obfervable upon divers kinds o{putn^ahodms, whether Ani- mal fubff ancesjor Vegetable,fiich as the fkin, raw or dtefs’d, ficfh,b]oud, humours, milk, green Cheefe,^c. or rotten feppy Wood, or Herbs, Leaves, Barks, Roots, of Plants, are all of them nothing elfe but fe- veral kinds of fmall and varioufly figur’d Mufhroms, which, from coni/e- nient materials in thofe putrifying bodies, are, by the concurrent heat of the Air, excited to a certain kind of vegetation, which will not be un- worthy our more ferious fpeculation and examination, as I (hall by and by fhew. But, firft, I muff premife a fliort defeription of this Specimen^ which I have added of this Tribe, in the firft Figure of the XII. Scheme, which is nothing elfe but the appearance of a fmall white fpot of hairy mould,multitudes of which I found to bofpeck & whiten over the red co- vers of a fmall book, which, it feems, were ofSheeps-fkin,that being more apt to gather mould, even in a dry and clean room, then other leathers^ Thefe fpots appear d,through a gpqdMieroJcope, to be a very pretty ftiap’d Vegetative body, which, from almoft the fame part of the Leather, fhbt
Micrographia.
out multitudes of fmall long cylindrical and tranlparent ftalks,not exad- Jy ftreightjbut a little bended with the weight of a round and white knob that grew on the top of each of them ^ many of tliefe knobs I obferV’d to be very round, and of a fmooth furface, fuch as A A, others fmooth likewife,but a little oblongjas B j feveral of them a little broken, or cloven with chops at the top, as C ^ others flitter’d as ’twere, or flown all to pieces, as D D. The whole fubftance of thefc pretty bodies was of a very tender conftitution, much like the fubftance of the (bfter kind of common white Mulhroms, for by touching them with a Pin, I found them to be brufed and torn ^ they leem’d each of them to have a di- ftinft root of their own 5 for though they grew neer together in a clufter, yet I could perceive each ftem to rife out of a diftinft part or pore of the Leather j fome of thefe were ftnall and fhort, as (eeming to have been but newly fprung up, of thefo the balls were for the moft part round, others were bigger,and taller,as being perhaps of a longer growth, and of thefe, for the moft part, the heads were broken, and fome much wafted, as E 3 what thefe heads contain’d I could not perceive 5 whether they were knobs and flowers, or feed cafes, I am not able to fey, but they feem’d moft likely to be of the fame nature with thofe that grow onMufliroms, which they did,fome of them, not a little refemble.
Both their Imell and tafte, which are aftive enough to make a fenfible impreflion upon thofe organs, are unpleafant and noifome.
I could not find that they would fo quickly be deftroy’d by the adual flame of a Candle, as at firft fight of them I conceived they would be,but they remain’d intire after I had paft that mrt of the Leather on which they ftuck three or four times through the flame of a Candle^ fo that, it Icems they arc not very apt to take fire, no more then^the common v/hite Mufhroms are when they are fappy.
There are a multitude of other (hapes, of which thefe Microfiopical Muftiroms are figur’d, which would have been a long Work to have de- fcribed,and would not have fuited fo well with my defign in this Treatife, oneIy,amongft the reft, I muft not forget to take notice of one that was a little like to, or refembled, a Spunge, confifting of a multitude of little Ramifications almoft as that body does, which indeed feems to be a kind of Water-Mulhrom, of a very pretty texture, as I elfe-where manifeft. And a fecond, which I muft not omit, becaufe often mingled, and neer adjoining to thefe I have deferib’d,and this appear’d much like a Thicket of bufties, or brambles, very much branch’d, and extended,fome of them, to a great length,in proportion to their Diameterdike creeping brambles.
The manner of the growth and formation of this kind of Vegetable, is the third head of Enquiry ,which, had I time,I fliould follow : the figure and method of Generation in this concrete feeming to me, next after the Enquiry into the formation, figuration, or chryftalization of Salts, to be the moft fimplc, plain, and eafie^ and it feems to be a ntedinm through which he muft neccflarily pals, that would with any likelihood inveftigate t\iQ forma informans of Vegetables ; for as I think that he Ihall/ find it a very difficult talk, who undertakes to difcover the form of Sa- line
M ! C R O G R A P H I A. 12’J
line cryftallizationsj without the coiifideration nnd prefcience of the na- ture and reafon of a Globular form, and as difficult to eicpiicate this con- figuration of Mufhroms, without the previous confideration of the form of Salts; lb will the enquiry into the forms of Vegetables be no lefs, if not much more difficult, without the fore-knowledge of the forms of Mulhroms, thefe feveral Enquiries having no left dependance one up- on another then any feleft number of Propofitions in Mathematical Ele- ments may be made to have.
Nor do I imagine that the Ikipsfrom the one to another will be found very great, if beginning from fluidity, or body witliout any form, we delcend gradually,till we arrive at the higheft form of a bruite Animals Soul, making the fteps or foundations of our Enquiry, Fluidity. Orbicn^ lation^ Fixation^ Angulii^ation^ or CryJid//iz,atiou Germination or Ebulli- tion. VegetuiionJ^lant animation^ Animation.^ Seujation^ Imagination.
Now, that we may the better proceed in our Enquiry, It will be re- quifite to confider :
Firft, that Mould and Mulhroms require no feminal property, but the former may be produc’d at any time from any kind of futrifying Animal, or Vegetable Subftance,as Flelh,€>'’c. kept moift and Warm, and the latter, if what Mathiolm relates be true, of making them by Art, are as much within our command, of which Matter take the Epitomie which Mr, Farkjnfon has deliver’d in his Herbal^ in his Chapter of MnJl)roms^ becaufe I have not Mathiolus now by me : Unto thefe MufrotHs (laith he) may dlfo be adjoynd tbofe rohich are made of Art (m^ere^Mathiolus makes men- tion) that grow naiufaUy ainong certain jiones in Naples, and that the fiones being digged np^ and carried to Rome, and other places^ where they fet them in their Wine Cellars^ covering them with a little Earth^and Jprin^ ling a little ioarm water thereon.^ would within four days produce Mufroms fit to be eaien^ at what time one will : As alfo that Mujlsioms may be made to grow at the foot of a wilde Poplar Tree, within four days after ^ warni fpater wherein fome leaves have been difiolvd f!?all be pour d into the Root (which mnfi be flit) and the flocks above ground.
Next, that as Mufhroms may be generated without feed, fo does it not appear that they have any luch thing as feed in any part of them ; for having confidered feveral kinds of them, I could never find any thing in them that I could with any probability ghefs to be the feed of it, fo that it does not as yet appear (that I know of) that Mulhroms may be ge- nerated from a feed, but they rather feem to depend merely upon a con- venient conftitution of the matter out of which they are made, and a concuriience of either natural or artificial heat.
Thirdly, that by feveral bodies (as Salts and Metals both in Water and in the air, and by feveral kinds of ffiblimations in the Air) actuated and guided with a congruous heat, there may be produc’d feveral kinds of bodies as curioufly, if not of a more compos’d Figure ; feveral kinds of riling or Ebulliating Figures feem to fnanifefi: ; as witnels the (hooting in the Reftiftcation of Ipirits oFUrine^ Hart-horn^ Bloud^ See. witnels alibi the curious branches of evaporated diflolutions, feme of them againft
128 Ml CROGRAPHIA.
the fid es of the containing Jar : others (landing up, or growing an end, out of the bottom, of which I have taken notice of a very great variety. But above all the reft, it is a very pretty kind of Germination which is af- forded us in the Silver Tree, the manner of making which with Mercury and Silver, is well known to the Chymifts, in which there is an Ebullition or Germination, very much like this of Muihroms, if I have been rightly inform’d of it.
Fourthly, I have very often taken notice of, and alfoobferv’d with a Microfeope^ certain excrefcencies or Ebullitions in the (huff of a Candle, which, partly from the (licking of the (moaky particles as they are car- ryed upwards by the current of the rarify’d Air and flame, and partly alfo from a kind of Germination or Ebullition of fome aduated unduous parts which creep along and filter through fome fmall ftring of the Week, are formed into pretty round and uniform heads, very much relembling the form of hooded Mufhroms, which, being by any means expos’d to the frefh Air, or that air which encompalfes the flame, they are prefently lick’d up and devour’d by it, and vanifh.
The reafon of which Phenomenon (eems to me, to be no other then this :
That when a convenient thread of the Week is fo bent out by the fides of the fnuff that are about half an Inch or more, remov’d above the bottom,or lowed part of the flame, and that this part be wholly included in the flame 5 theOyl (for the rea(bn of filtration, which I have cKe- where rendred) being continualy driven up the (huff^ is driven like- wife into this ragged bended-end , and this being remov’d a good diftance, as half an Inch or more, above the bottom of the flame, the parts of the air that pafles by it, are already, almoft fatiated with the di(^ (blution of the boiling unftuous (learns that ifliied out below, and there- fore are not onely glutted, that is, candiflblve no more then what they are already aiding upon, but they carry up with them abundance of uniduousand footy particles, which meeting with that rag of the Week, that is plentifully fill’d with Oyl, and onely (pends it as fad as it evapo- rates, and not at all by difldlution or burning, by means of thefe fteamy parts of the (literate d Oyl ifluing out at the fides of this ragg, and being inclos’d with an air that is already (atiated and cannot prey upon them nor burn them, the alcending (boty particles are ftay’d about it and fix’d, (b as that about the end of that ragg or filament of the fnuff, whence the greateft part of the (learns ifliie, there is conglobated or fix’d a round and pretty uniform cap, much relembling the head of a Muftirom, which, ifit beof any great bignels, you may oblerve that its underfid e will be bigger then that which is above the ragg or ftem of it , for the Oyl that i^ brought into it by filtration,being by the bulk of the cap a little fhelter’d from the heat of the flame, does by that means iflue as much out from be-^ neath from the ftalk or downwards, as it does upwards, and by realbn of the great accels of the adventitious (moak from beneath, it increales mod; that way. That this may be the true reafon of this Phenomenon^ I could produce many Arguments and Experiments to make it probable ; As,
Firft, that the Filtration carries the Oyl to the top of the Wcck,at lead
as
Micrographia.
as high as thefe raggs^ is vifible to one that will obferve the TnufT of A burning Candle with a Microfcope^ where he may fee an Ebullition or bubbling of the Oyl, as high as the fnufFlooks black.
Next,that it does fteam away more then burn 5 I could telkyou of the dim burning of a Candlcj the longer the fnuff be which arifes from the abundance of vapours out of the higher parts of it.
And, thirdly, that in the middle of the flame of the Candle, heer the top of the fnuff, the fire or diflbl ving principle is nothing neer fo ffrongj as neer the bottom and out edges of the fl.ame, which may be obferv’d by the burning afunder of a thread, that will firfl: break in thofe parts that the edges of the flame touch, and not in the middle.
And I could add feveral Obfervables that I have taken notice of in the flame ofa Lamp aduated with Bellows, and very many others that con= firm me in my opinion, but that it is not fo much to my prefent purpofe, which is onely to coniider this concreet in the fniiff of a Candle, fo farr as it has any refemblance of a Mufhrom, to the confideration of which, that I may return, I fay, we may alfo obferve ;
In the firft place, that the droppings or trillings of Lapidefcent waters in Vaults under ground,feem to conffitute a kind oCpetriJy'd body,form’d almofflike feme kind ofMufhroms inverted,in fo much that I have feen fomeknobb’d a little at the lower end, though for the moft part, indeed they are otherwife fhap’d,and taper’d towards the endj the generation of which feemsto be from no other reafon but this, that the water by fbak- ing through the earth and Lime (fori ghefs that fubftance to add much to It petrifying quality) does fb impregnate it felf withftony particles, that hanging in drops in the roof of the Vault , by reafon that the leaking of the water is but flow, it becomes expos’d to the Air, and there- by the outward part of the drop by degrees grows hard, by reafon that the water gradually evaporating the ftony particles neer the outfides of the drop begin to touch, and by degrees, to dry and grow clofer toge- ther, and at length conft itute a cruft or fhell about the drop 5 and this Ibaking by degrees, being more and more fupply’d, the drop grows longer and longer, and the fides harden thicker and thicker into a Quill or Cane, and at length, that hollow or pith becomes almoft ftop’d up, and folid : afterwards the foaking of the petrifying water, finding no longer a pafl&ge through the middle, burfts out, and trickles down the outfide, and as the water evaporates, leaves new foperinduc’d fhellsj which more and more fwell the bulk of thole Iceicles x and becaule of the great fupply from the Vault, o^ petrifying water, thole bodies grow bigger and bigger next to the Vault, and taper or fharpen towards the point 3 for the accefi from the arch of the Vault being but very flow,and conlequently the water being Ipread very thinly over the llirface of the Iceicle, the water begins to lettle before it Can reach to the bottom, or corner end of it 3 whence, if you break one of thele, you would almoft imagine it a ftick of Wood petrify it having fo pretty a relemblance of pith and grain , and if you look on the outfide of a piece, or of one whole, you would think no left, both from its vegetable roundneft and
T tapering
1^0 M I C R O G R A P H I A,
tapering form^ but whereas all Vegetables are oblery’d to flioot and grow perpendicularly upwards , this does flioot or propend diredly downwards.
By which lafl: Obfervables, we lee that there may bq a very pretty body fliap’d and concreeted by Mechanical principles, without the leaft (hew or probability of any other feminal formatrix.
And fince we find that the great reafon of the Thanomeva of this pret- ty petrifaBion^ are to be reduc’d from the gravity of a fluid and pretty volatil body impregnated with ifony particles, why may not the rham- mena of Ebullition or Germination be in part poffibly enough deduc’d from the levity of an impregnated liquor, which therefore perpendicu- larly afeending by degrees, evaporates and leaves the more folid and fix’d parts behind in the form of a Muflirom, which is yet further diverfi- fy’d and Ipecificated by the forms of the parts that impregnated the li- quor, and compofe or help to conftitute the Mufhrom.
That the foremention’d Figures of growing Salts, and the Silver Tree, are from this principle, I could very eafily manifefi: 5 but that I have not now a convenient opportunity of following it, nor have I made a fiiflici- ent number of Experiments and Obfervations to propound, explicate,and prove fb ulefull a "Theory as this of Mufliroms ; for, though the con- trary principle to that of petrify d Iceicles may be in part a caufe , yet I cannot but think, that there is fbmewhat a more complicated caufe, though yet Mechanical, and poffible to be explain’d.
We therefore have further to enquire of it, what makes it to be fuch a liquor, and to afeend, whether the heat of the Sun and Air, or whe- ther that of firmentiation and pntrifaBion^ or both together 5 as alfb whe- ther there be not a third or fourth 5 whether a Saline principle be not a confiderable agent in this bufinels alfo as well as heat , whether alfb a fixa- tion, precipitation or fettling of certain parts out of the aerial Mufhrom may not be alfb a confiderable coadjutor in the bufinefs. Since we find that many pretty beards or Jiiri£ of the particles of Silver may be preci- pitated upon apiece of Brafs put into ajolution of Silver very much di- luted with fair water, which look not unlike a kind of mould or hoar upon that piece of metal 5 and the hoar froft looks like a kind of mould 5 and whether there may not be feveral others that do concurr to the pro- duftion of a Mufhrom, having not yet had fufficient time to profecute ac- cording to my defires, I muft referr this to a better opportunity of my own, or leave and recommend it to the more diligent enquiry and exa- mination offlich as can be mafters both of leifurc and conveniencies for fiich an Enquiry.
And in the mean time, I muft conclude, that as far as I have been able to look into the nature of this Primary kind of life and vegetation, I can- not find the leaft probable argument to perfwadc me there is any other concurrent caufe then flichas is purely Mechanical, and that the eflbds or produftions are asneceflary upon the concurrence of thofe caufes as that a Ship, when the Sails are hoift up, and the Rudder is fet to fuch a pofition,fhould,when the Wind blows, be mov’d in fuch a way or courfe
to
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MigrOgraphia;
to that or t’other place 5 Or, as that the brufed Watch, which I men- tion in the defcription of Mofs, fhould, when thofe parts which hindred its motion were fallen away, begin to move, but after quite another man- ner then it did before.
Obferv. X X 1 . Of Mofs, and fever al other fmall vegetative SuB- fiances,
Ti A Ofs is a Plant, that the wifeft ot' Kings thought neither unworthy iV| his fpeculation, nor his Pen, and though amongft Plants it be in bulk one of the fmallelf , yet it is not the lead: confiderable : For, as to its (hape, it may compare for the beauty of it with any Plant thatgrowsj and bears a much bigger breadth 3 it has a root almoft like a feedy Parl^ nep, furnilh’d with fmall ftrings and fuckers, which are all of them finely branch’d, like thofe of the roots of much bigger Vegetables 5 out of this fprings the ffera or body of the Plant, which is foitiewhat g>uadraKgHlar^^ rather then Cylindrical^ moft curioully or ftrung with Imall creafes, which ruojfor the mod: ^2xt^paralIel t\\Q whole ftem 5 on the fides of this are dole and thick fet, a multitude of fair3large,well-diap’d leaves, (bme of them of a rounder, others of a longer fhape, according as they are younger or older when pluck’d 5 as I ghels by this, that thole Plants that had the (talks growing from the top of them, had their leaves of a much longer (bape, all the furface of each fide of which, is curioully cover’d with a multitude £>f little oblong tranfparent bodies, in the manner as you lee it exprels’d in the leaf B, in the XIII. Scheme,
This Plant, when young and fpringing up, does much relemble a Houfi- leek,having thick leaves,almod: like that, and feems to belbmwhatofkin to it in other particulars 3 allb from the top of the leaves, there (hoots out a (mail white and tranfparent hair, or thorn : This ftem, in time,comc to (hoot out into a long,roundand even Ifalk, which by cutting tranlverfly, when dry, I manifeftly found to be a (fid, hard, and hollow Cane, or Reed, without any kind of knot, orftop, from its bottom, where the leaves encompals’d it, to the top, on which there grows a large feed cafe, A, cover’d with a thin, and more whitifb (kin, B, terminated in a long thorny top, which at firft covers all the Cafe, and by degrees, as that fwells, the (kin cleaves, and at length falls off, with its thorny top and all (which is a part of it) and leaves the feed Cafe to ripen, and by degrees, to fhatter out its feed at a place underneath this cap, B, which before the feed is ripe, appears like a flat barr’d button, without any hole in the middle^ but as it ripens, the button grows bigger, and a bole appears in the middle ofit, E, outofwhich, in all probability, the feed falls ; For as it ripens by a provifionof Nature, that end of this Cafe turns down<^ ward after the fame manner as the ears of Wheat and Barley ufually do ; and opening feveral of thefe dry red Cafes, F, I found them t6 be
T 2 quite
132
MiCROGR AP H I A.
quite hollowjwithout any thing at all in them 5 whereas when I cut them afunder with a fharp Pen-knife when green, I found in the middle of this great Cafe,another fmaller round Cafejbetwcen which two,the interjlices were fill’d with multitudes of ftringie fibres ^ which feem'd to fufpend the Idler Cafe in the middle of the other, which (as farr as I was able to dip cern) feem’d full of exceeding fmall white feeds, much like the feed-bagg in the knop of a Carnation , after the flowers have been two or three days, or a week,fallen off^ but this I could not fo perfectly difeern, and therefore cannot pofitively affirm it.
After the feed was fallen away, I found both the Cafe, Stalk,and Plant, all grow red and wither, and from other parts of the root continually to ipring new branches or flips, which by degrees increafed, and grew as bigg as the former, feeded, ripen’d, fhatter’d, and wither’d.
I could not find that it obferv’d any particular feafons for thefe feveral kinds ofgrowth, but rather found it to be fpringing, mature, ripe, feedy, and wither’d at all times of the year 3 But I found it moft to flourifh and increafe in warm and moifi: weather.
It gathers its nourifhments,for the moft part, out of fome Lapidefeent^ot other fubftance corrupted or chang’d from its former texture, or fub- ftantial form 3 for I have found it to grow on the rotten parts of Stone, of Bricks, of Wood, of Bones, of Leather, cfic.
It oft grows on the barks of feveral Trees, fpreading it felf^ fometimes from the ground upwards, and fometimes from feme chink or cleft of the bark of the 1 ree, which has fome putrifyd fubftance in it 3 but this feems of a diftinft kind from that which I obferv’d to grow on pHtriffid inanimate bodies, and rotten earth.
There are alfb great varieties of other kinds of Mofles, which grow on Trees, and feveral other Plants, of which I fhall here make no mention, nor of the Mofs growing on the fkull of a dead man, which much re- lembles that of Trees.
Whether this Plant does fometimes originally fjpring or rife out of cor- ruption,without any difleminated feed, I have not yet made trials enough to be very much, either pofitive or negative 3 for as it feems very hard to conceive how the feed fhould be generally difpers’d into all parts where there is a corruption begun, unlefs we may rationally fuppofe, that this feed being fo exceeding fmall,and confequently exceeding light ,is there- by taken up, and carried to and fro in the Air into every place, and by the falling drops of rain is wafh’d down out of it, and fo difpers’d into all places, and there onely takes root and propagates, where it finds a con- venient foil or matrix for it to thrive in 3 fb if we will have it to proceed from corruption, it is not left difficult to conceive,
Firft, how the corruption of any Vegetable, much left of any Stone or Brick, fhould be the Parent of fo curioufly figur’d, and fo perfe^ a Plant as this is. But here indeed, I cannot but add, that it feems rather to be a produft: of the Rain in thofe bodies where it is flay’d, then of the very bodies themfelves, fince I have found it growing on Marble, and Flint 3 but always the A^icrofiope^ if not the naked eye, would difeover fome little hole of Dirt in which it was rooted. Next,
MicROGR A P H i A.
Nextjhow the corruption of each ofthoie exceedingly differing bodies fhould all confpirc to the produdion of the fame Plant, that is, that Stones, Bricks, Wood, or vegetable fubftances, and Bones, Leather, Horns, or animate fubfcances, unlefs we may with (bmc plahfiblenefs lay, that Air and Water are the coad jutors, or menjirunmy’m all kinds oipHtrifa^ioTis^ and that thereby the bodies (though wbifft they retain’d their fubftan- tial formsjwere of exceeding differing natures,yet)fincc they arediffblv’d and mixt into another, they may be very Homogeneous^ they being almoff: rcfolv’d again into Air, Water, and Earth5retaining,perhaps,one part of their vegetative faculty yet entire, which meeting with congruous af- fiftants, fuch as the heat of the Air, and the ffuidity of the Water, and filch like coadjutors and conveniences, acquires a certain vegetation for a time, wholly differing perhaps from that kind of vegetation it Bad before.
To explain my meaning a little better by a grofs Similitude ;
Suppofe a curious piece of Clock-work, that had had feveral motions and contrivances in it, which, when in order, would all have mov’d in their defign’d methods and Periods. We will further fuppofe, by fbme means, that this Clock comes to be broken, bruled, or otherwife difbr° dered, fo that feveral parts of it being diflocated, are impeded, and fo (land ff ill, and not onely hinder its own progreffivc motion, and produce not the effed which they were defign’d for, but becaufe the other parts alfb have a dependence upon them, put a flop to their motion likewife 5 and lb the whole Inftrument becomes unferviceable,, and not fit for any ufe. This Inftrument afterwards, by fbme (baking and tumbling, ana throwing up and down, comes to have feveral of its parts fhaken out, and feveral of its curious motions, and contrivances, and particles all fallen afunder , here a Pin falls out, and there a Pillar, and here a Wheel, and there a Hammer, and a Spring, and the like, and among the reft, away falls thofe parts alfb which were bru(ed and diforder’d, and had all this while impeded the motion of all the reft 5 hereupon feveral of thofe other motions that yet remain, whofe fprings were not quite run down, being now at liberty, begin each of them to move,thus or thus, but quite after another method then before, there being many regulating parts and the iike,fallen away and loft. Upon this, the Owner, who chances to hear and obfervefome of thefe effedfs, being ignorant of the Watch-makers Art, wonders what is betid his Clock, and prefently imagines that fome Artift has been at work, and has fet his Clock in order, and made a new kind oflnftrument of it, but upon examining circumftances,he finds there was no fiich matter, but that the cafual flipping out of a Pin had made feveral parts of his Clock fall to pieces, and that thereby the ob*> ftacle that all this while hindred his Clock, together with other ufefull parts were fallen out, and fb his Clock Was fet at liberty. And upon winding up thofe fprings again when run down, he finds his Clock to go, but quite after another manner then it was wont heretofore.
And thus may it be perhaps in the bufinefs of Mofs and Moulds^ and Mufhroms, and feveral other fpontaneous kinds of vegetations, which
may
1^4 Micrograhp I A.
may be caus’d by a vegetative principle, which was a coadjutor to the life and growth of the greater Vegetable, and was by the deftroying of the life of it ftopt and impeded in performing its office , but after- wards, upon a further corruption of feveral parts that had all the while impeded it, the heat of the Sun winding up, as it were, the fpring, lets it again into a vegetative motion, and this being fingle,and not at all regu- lated as it was before(when a part o f that greater machine the priftine ve- getable)is mov’d after auite a differing manner,and produces effeds very differing from thofe it did before.
But this I propound onely as a conjedure, not that I am more enclin’d to this Hj/potheJfs then the feminal, which upon good reafon 1 ghels to be Mechanical alfo^ as I may ellewhere more fully fhew: But becaufe I may, by this, hint a pofiible way how this appearance may be folv d ^ fiippofing we fhould be driven to confefs from certain Experiments and Obfervati- ons made, that ffich or luch Vegetables were produc’d out of the cor- ruption of another, without any concurrent feminal principle (as I have given fbme reafon to fuppofe, in the defeription of a Alicrojcopical Mufh- rome) without derogating at all from the infinite wifdom of the Creator. For this accidental produdion, as I may call it, does manifeft as much, if not very much more, of the excellency of his contrivance as any thing in the more perfed vegetative bodies of the world, even as the accidental motion of the Automaton does make the owner fee, that there was much more contrivance in it then at firft he imagin’d. But of this I have added more in the defeription of Mould,and the Vegetables on Role leaves,e^c. thole being much more likely to have their original from fuch a caufe then this which I have here deferibed, in the 13. Scheme^ which indeed I cannot conceive otherwile of, then as of a moft perfed Vegetable, want- ing nothing of the perfedions of the moft conlpicuous and vafteft Vege- tables of the world, and to be of a . rank lb high, as that it may very properly be reckon’d with the tall Cedar of Lebanon^ as that Kingly Botanift has done.
We know there may be as much curiofity of contrivance, and exeeb lency of form in a very Imall Pocket-clock, that takes not up an Inch fquare of room,as there may be in a Church-clock that fills a whole room 5 And I know not whether all the contrivances and Mechanifms requifite to a perfed Vegetable, may not be crowded into an exceedingly left room then this of Moft, as I have heard of a ftriking Watch lb final!, that it ferv’d for a Pendant in a Ladies ear 5 and I have already given you the delcription of a Plant growing on Role leaves, that is abundant- ly fmaller then Moft, infomuch, that neer 1000. of them would hardly make the bigneft of one fingle Plant of Moft. And by comparing the bulk of Mols, with the bulk of the biggeft kind of Vegetable we meet with in Story (of which kind we find in fome hotter climates, as Guine^ and Brajik, the ftock or body of Ibme Trees to be twenty foot in Dia- meter, whereas the body or ftem of Moft, for the moft part, is not above one fixtieth part of an Inch) we fhall find that the bulk of the one will exceed the bulk of the other, no left then 2985984 Millions,
or
MiCROGRAPHiA.
or 29859840000005 and fuppofing the prodiKTdoh on a Rofe leaf to be a Plant, we (hall have of thofe Itidian Plants to exceed a produ^Hon of the lame Vegetable kingdom no lels then 1000 times the former number 5 lb prodigioully various are the works of the Creator,and lb All-lufficient is he to perform what to man would feem unpohible, they being both alike eafie to him, even as one day, and a thoufand years are to him as one and the fame time.
I have taken notice of luch an infinite variety ot thofe Imaller kinds of vegetations, that Ihouldlhave defcribed every one of them,they would almoft hav^ fill’d a Volume, and prov d bigg enough to have made a new Herbal, luch multitudes are there to be found in moift hot weather, efpecially in the Summer time, on all kind of putrifying fubftances, which, whether they do more properly belong to the Clajjir of or
Moulds^ or Mojfes^ I lhall not now difpute, there being Ibme thatleem more properly of one kind, others of another , their colours and magnitudes being as much differing as their Figures and lubftances.
Nay, I have obferv'd,that putting fair Water (whether Rain-water or Pump-water, or May-dew^ or Snow-water, it was aimoff: all one) I have often obferv’d, I fay, that this Water would, with a little ftanding, tarniffi and cover all about the lides of the Glafs that lay under water, with a lovely green 5 but though I have often endeavour’d to difeover with my Microscope whether this green were like Mols,or long ffrriped Sea> weed, or any other peculiar form, yet fo ill and imperfed are our Microfeopes^ that I could not certainly diferiminate any.
Growing Trees alfo, and any kinds of Woods, Stones, Bone^j that have been long expos'd to the Air and Rain, will be all over cover’d with a greenifh feurff, which will very much foul and green any kind of cloaths that are rubb’d againff: it, viewing this, I could not certainly perceive j in many parts ofit any determinate form,though in many I could perceive , a Bed as ’twere of young Mofs, but in other parts it look'd almoft like t green bufnes,and very confus’d,but always of what ever irregular Figures I the parts appear’d of, they were always green, and feem’d to be either j fome Vegetable, or to have Ibme vegetating principle.
Obferv, XXII. Dj common Sponges, and fever at other Spongie
A Sponge is commonly reckon’d among the Zoophyts^ or Plant Ani- mals 5 and the of it,which the Microjeope dilcovers, (cems to
I confirm it ; for it is of a form whereof I never obferv’d any other Vege- . \ table, and indeed,it feems impolfible that any fhould be of it, for it con- ■ I fifts of an infinite number of fmall fhort fibres^ or nervous parts, much of f? the fame bignefs, curioufly jointed or contex’d together in the form cl of a Net, as is more plainly manifeft by the little Draught which I have
added
I
Ml CROGR AP HIA.
added, in the third Figure of the I X. Scheme^ of a piece of it, which yon may perceive reprefents a confus’d heap of the fibrous parts curioully jointed and implicated. The joints are, for the mod: part, where three fibres onely mcet,for I have very feldom met with any that had four.
Atthefe joints there is no one of the three that leems to be theftock whereon the other grow, but each of the fibres are, for the moft part, of an equal bignefs, and feem each of them to have an equal (hare in the joint 5 the fibres are all of them much about the fame bignefs, not finaller towards the top of the Sponge, and bigger neerer the bottom or root, as is ufiiall in Plants, the length of each I^tween the joints, is very irregu- lar and different 5 the diftance between fome two joints, being ten or twelve times more then between fome others.
Nor are the joints regular, and of an equitriagonal Figure^ but,forthe moft part, the three fibres lb meet, that they compofe three angles very differing all of them from one another.
The mefhes likewife, and holes of this reticulated body, are not left various and irregular : fome bilateral^ others trilateral^ and quadrilateral Figures, nay, I have obferv’d fome mefhes to have 5, 6, 7,8, or 9. fidcs, and fome to have onely one, fb exceeding various is the Lufits Natura in this body.
As to the outward appearance of this Vegetative body, they arefo ufiiall every where, that I need not deferibe them, confifting of a foft and porous fubftance, reprefenting a Lock, Ibmetimes a fleece of Wooll 5 |j butit hasbefides thele fmall microfcopical pores which lie between the j fibres^ a multitude of round pores or holes, which, from the top of it, pierce into the body, and fbmetimes go quite through to the bottom.
I have obferv’d many of thefe Sponges, to have included likewife in the midft of their fibrous contextures, pretty large friable ftones, which muft either have been inclos’d whil’ft this Vegetable was in formation,or generated in thole places after it was perfedly fhap’d. The later of which feems the more improbable, bccaufe I did not find that any of thefe ftony fubftances were perforated with the fibres of the Sponge.
I have never feen nor been enform’d of the true manner of the grow- ing of Sponges on the Rockjwhether they are found to increafe from little to great,like Vegetables,that is, part after part, or like Animals, all parts equally growing together, or whether they be or feed-baggsof
any kind of Fifties, or fome kind of watry Infed , or whether they are at any times bore foft and tender, or of another nature and texture, which things, if I knew, I ftiould much defire to be informed of; but from a curfory view that I at firft made with my Microfeope^ and fome other trials,! fuppofed it to be fome Animal fubftance caft out, and faftned up- | on the Rocks in the form of a froth, or congeries of bubbles, like that which I have often obferv’d on Rofemary, and other Plants (wherein I is included a little Infcdf) that all the little films which divide thefe I bubbles one from another,did prefently,almoft after the fubftance began II to grow a little harder,break,and leave onely the thread behind, which 1 1 might be, as ’twere, the angle or thread between the bubbles, that the I
great I
M I C R O G k A P H i A. 13^
gteat holes or pores oblervable in thcfe Sponges were made by the erii*^^ ption of the included Heterogeneous fubftance (whether air, or fomc' other body, for many other fluid bodies will do the fame thing) which breaking out of the lelTer, were colleded into very large bubbles, arid fo might make their way out of the Sponge, and in their paflage might leave a round cavity ^ and if it were large, might carry up with it the ad- jacent bubbles, which may be perceiv’d at the outfide of the Sponge, if it befirll throughly wetted, and fuffefd to plump it felf into its natural form, or be then wrung dry, and fuffefd to expand it felf again, which it will freely do whifftmoifl: ; for when it has thus plump’d it felf into its natural fhape and dimenfions, ’tis obvious enough, that the mouths of the larger holes have a kind of lip or riling round about them, but the other finaller pores have little or none. It may further be found, that each of thefe great pores has many other fmall pores below, that are united untof it, and help to conftitute it, almoft like fb many rivulets or (mall flreamS that contribute to the maintenance of a large River. Nor from this Hyfothejis would it have been difficult to explicate, how thofe little branches of Coral^ (mal Stones^ shells^ and the like, come to be included by thefe frothy bodies : But this indcd was but a conjedfure ^ and upon a more accurate enquiry into the form of it with the Microfeope^ it feems not to be the true origine of them 3 for whereas Sponges have onely three arms which join together at each knot, if they had been generated' from bubbles they muft have had four. '
But that they are Animal Subfiances, the examinatipn "of
them feems to manifeft, they affording a volatil Salt and fpirit, like Horn^ as does alfo their great ftrength and toughnefs, and their fmell when burn’d in the Fire or a Candle, which has a kind of fiefby fent,not much unlike to hair, And having fince examin’d feveral Authors con- cerning them,among others,! find this account given by 'Bellonius^ irr the Xl.C^^p.of his Book, De Aqtiatilibus. Spongia recehtes^Cuys
longe diverja^fcopulis aqu<e marina ad duos vd tres cubitos^nonnunquani qua- tuer tantun^ digitos immerjis, ut fungi arboribns adharent, Jordido qtrodafii Jucco aut mucoja potius fanie refarta^ujque adebfetida^ut tiel emimts naitfeani €xcitet^ continetur autem ik cavernk^ quas inanes in ftcck lotis Spangfk
cernimns : Vntrispulmonk modo nigra conjpiciuntur^ ’veriim qua in jublimi aqua najcuntur multo magis opaca nigredine fiiffufa Junt. Fivers quidem Sppngias adbuerendo Ar\{[ot€]es cenjet : abfolute vero minims : fenjumqne aliquem habere^ vel eo argumento (inquit') credantur^ quod d^ciUime ab- frahantur^niji clanculum agatur:Atq’^ ad avulforis accejjum it a contrahahtUfj ut eas evelkre dificile jit^ quod idem etiam faciunt quoties flatus tempejia- tijque urgent. Tuto autem illk Juccum fordidum quern jupra \diximui car- nis loco a natura attributum fuijje : atque meatibus latioribtk^ tan- quam inteflinis aut inter anek uti. Caterum pars ea qua Spongi a caiitibus adharent efi tanquam folii petiolus ^ a quo >veluti collum quoddam g\raciUin- cipit : quod deinde in latitudinem diflufum capitk globum facit. KicSfiiibW nihil efi fifinlofitm^ hafitantque tanquam radicibm. Superne omnes p/cftmo^ dum meatus concreti latent : Infer ne verb quaterni aut quini paten fpbr qnos
V
Micrographia.
eas fugere exifiimamus. From which Defcription, they fecm to be a kind of Plant- Animal that adheres to a Rockland thefe fmall fibres or threads which we have defer ibed, feem to have been the Veflels which (’tis very probable) were very much bigger whirft the Interjlitia were fill’d (as he affirms) with a mucousjpulpy or flelhy fubftance 5 but upon the drying were Ihrunk into the bignefs they now appear.
The texture of it is fuch, that I have not yet met with any other body in the world that has the like, but onely one of a larger fort of Sponge (which is preforv’d in the Mufieum Harveanum belonging to the moft Illuftrious and moft learned Society of the Thyficians of Londoti) which is of a homey, or rather of a fetriffa fubftance. And of this indeed, the texture and make is exadly the fame with common Sponges, but onely that both the holes and the fibres^ or texture of it is exceedingly much bigger,for fome of the holes were above an Inch and half over, and the fibres and texture of it was bigg enough to be diftinguiftied eafily with ones eye, but confpicuoufly with an ordinary fingle Afjcrofiepe. And thefo indeed, feem’d to have been the habitation of fome Animal ^ and qx'- ^mmmgArifiotle^ I find a very confonant account hereunto, namely, that he had known a certain little Animall, call’d Twnotheraj like a Spider, to be bred in thofe'eaverns of a Sponge,from within which,by opening and clofing thofe holes, he inlhares and catches the little Fiihes^ and in ano- ther place he fays, That’tis very confidently reported, that there are cer- tain Moths or Worms that refide in the cavities ol’ a Sponge, and are there nourifted ; Notwithftanding all which Hiftories,! think it well worth the enquiring into the Hiftory and nature of a Sponge, it Teeming to promife fome information of the Veffels in Animal iubftances, which (by reafon of the folidity of the interforted flelh that is not eafily remov’d, without deftroying alfo thofe interfpers’d Veflels ) are hitherto undifoover’d 5 whereas here in a Spongc,the Parenchyma’ll fecms,is but a kind of mucous gelly, which is very eafily and cleerly wafli’d away.
The reafon that makes me imagine, that there may probably be fome foch texture in Animal fubftances, is, that examining the texture of the filaments of tann’d Leather, 1 find it to be much of the fame nature and ftrength of a Sponge 5 and with my Microfeope^ I have obferv’d many fiich joints and knobs, as I have deforibed in Sponges, the fibres alfo in the hol- low, of foveral forts of Bones, after the Marrow has been remov’d, I have found fomewhat torelemble this texture, though, I confefs, I never yet found any texture exactly the fame, nor any for curiofity comparable to it.
The filaments of it are much fmaller then thole of Silk, and through the Micrefeope appear very ncer as tranlparent, nay, fome parts of them I have obferv’d much more.
Having examin’d alfo fevcral kinds of Muffiroms, I finde their texture to be fomewhat of this kind, that is, toconfift of an infinite company of finaU filaments, every way contex’d and woyeo together, fo as to make a kind of cloth, and more particnlarly, examining a piece of Touch- wood (which isa kind oijmji-ear^ot Mulhrom, growing here in £»^/<«Wallb,
on
Mi C ROGR APHIA.
on feveral forts of Trees, fuch as Elders, Maples, Willows, and is
commonly call’d by the name of Spuj^kj^ but that we meet with to bd lold in Shops, is brought from beyond Seas) I found it to be made of an exceeding delicate texture; For the fobftance of it feels, and looks to the naked eye,and may be ftretch’d any way ,exad:ly like a very fine piece of Leather, orwafh’d Leather, but it is of fomewhata brOwner.
hew, and nothing neer fo ftrong but examining it .with my Micrvfcopey, I found it of fomewhat another make then any kind ofLeathei^ fbfi whereas both chamois^ and all other kinds of Leather I have yet view’d,) confift of an infinite company of filaments, fomewhat like bulhes inter- woven one within another, that is,of bigger parts or ftems, as it were, and finaller branchings that grow out of them , or like a heap of Ropes ends, where each of the larger Ropes by degrees feeny to ^iit or untwjfj:, into many- imallef Cords, an^ each of thole Cords into Irhallet and
thofe Lines into Threads, &■€. and thefo ftrangely intangled, or inter- woven one within another .* The texture of this Touch- wood feem| more like that of a Lock or a Fleece: of Wool, for it confifts of an infinite number of fmall filaments, all of them, asfarr as hcould perceive^ of the fame bignels like thofo of a Sponge, but that \\\t filaments of this were not a twentieth part of the bignels of thofe of a Sponge 5 and I could not fo plainly perceive their joints, or their manner of interweaving, though, asfarrasi was able to difeern with that Mkrofcopel had, I fuppofeitto have fomekind ofrefemblance, but the joints are nothing neet fo thick, nor without much trdlible vifible.
The filaments I could plainly enough perceive to be evenjtoundjCylin- drical,tranlparent bodies,and to crofs each other every way, that is, there were not more feem’d to lie horizontally then perpendicularly and thwart-^ way, fo that it is fomewhat difficult to conceive how they Ihould grow in that manner. By tearing off a Imall piece of it, and looking on the ragged edge, I could among feveral fibres perceive fmall joints,
that is, one of thofe hairs fplit into two, each of the lame bignels with the other out of which they feem’d to grow, but having not lately had an opportunity of examining their manner of growth, I cannot pofitively af- firm any thing of them.
But to proceed. The fwelling of Sponges upon wetting, and the riling of the Water in it above the furface of the Water that it touches, are both from the lame caufe, of which an account is already given in the fixth Obfervation.
The fubftance of them indeed, has fo many excellent properties,foarcc to be met with in any other body in the world, that I have often won-^ dered that fo little ufe is made of it, and thofe ofiely vile and fordid 5 certainly, if it were well confider’d, it would afford much greater con- veniencies.
That ufe which the Divers are laid to make of it , feems, if true, very ftrange, but having made trial of it my felf, by dipping a fmall piece of it in very good Sallet-oyl,and putting it in my mouth,and then keep'* ing my mouth and nofe under water, I could not find any fuch thing 5 for I
V 2 was
MiCR O GR AP H I A.
was as foon out of breathjas ifl had had no Sponge,nor could I fetch my breath without taking in water at my mouth 5 but I am very apt to think, that were there a contrivance whereby the expir’d air might be forc’d to pafs through a wet or oyly Sponge before it were again infpir’d, it might much cleanfe, and ftrain away from the Air divers fuliginous and other noifome fteams, and the dipping of it in certain liquors might,
Eerhaps, fo renew that property in the Air which it lofes in the Lungs,by eing breath’d, that one fquarefoot of Air might lafta man for refpirati- on much longer, perhaps,then ten will now ferve him of common Air,
Obferv. XXIII. Of the curious texture of SeTi-vfceds,
FOr curiofity and beauty, I have not among all the Plants or Vege- tables I have yetobferv’d,(een any one comparable to this Sea-weed I have here dcicrib’d, of which I am able to fay very little more then what is reprelented by the fecond Figure of the ninth Scheme ; Namely, that it is a Plant which grows upon the Rocks under the water, and increafes and Ipreads it felf into a great tuft, which is not onely handlbmely branch’d into leveral leaves, but the whole furface of the Plant is cover’d over with a moft curious kind of carv’d work, which confifts of a tex- ture much refembling a Honey-comb , for the whole furface on both fides is cover’d over with a multitude of very fmall holes, being no bigger then lb many holes made with the point of a Iraall Finn, and rang’d in the neateft and moft delicate order imaginable, they being plac’d in the man- ner of a gluincunx^ or very much like the rows of the eyes of a Fly, the rows or orders being very regular, which way Ibever they are obferv’d : what the texture was, as it appear’d through a pretty bigg Magnifying Microfiepe, I have here adjoin’d in the firft Figure of the 14. Scheme » which round Area A B C D reprefents a part of the furface about one eighth part of an Inch in Diameter : Thole little holes, which to the eye look’d round, likefo many little Ipots, here appear'd very regularly lhap’d holes, reprefenting almoft the lhape of the foie of a round toed Ihoe, the hinder part of which, is, as it were, trod on or cover’d by the toe of that next below itjthele holes feem’d wall’d about with a very thin and tranlparent fubftance, looking of a pale ftraw-colour , from the edge of which, againft the middle of each hole, were fprouted out four fmall tranlparent ftraw-colqur’d Thorns, which feem’d to proteft and cover thole cavities, from either fide two , neer the root of this Plant, were fprouted out feveral fmall branches of a kind of baftard Cerallwe. curi- oufly branch’d, though Imall.
And to confirm this, having lately the opportunity of viewing the large Plant (ifl may fo call it) of a Sponge petrif/d^ of which I made mention in the laft Obfervatiouj I found, that each of the Branches or Figures of it, did, by the range of its pores, exhibit juft fuch a texture,
the
I \
/
r
M i C R O G R A P H I A ;
the rows of pores crofling one another, much after the manner as the rows of eyes do which are delcrib’dihthe i6.Scheme : ‘Coralline allbjand feveral forts of white Coral^ I have with a Alicrofcope obierv’d very cif rioufly ftiap’d. And I doubt not, but that he that (hall obferve thefc feveral kinds of Plants that grow upon Rocks, which the Sea fome- times overflows, and thofe heaps of others which are vomited out of it up- on the ihore, may find multitudes of little Plants, and other bodies, which like this will afford very beautifull objebfs for the Microfiopc ^ aqd thi§ Spedjnenhtte is adjoin’d onely to excite their curiofities who have op- portunity of obferving to examine and collefi: what they find worthy their notice j for the Sea, among terreflrial bodies, is alfo a pirdlijic^ mother, and affords as many Inffances of jj>ontaneous generations as ei- ther the Ail' or Earth.
Obferv. XXIV. Of the furfaces (/^ftolemary, and other leaves,
^ I His which is delineated within the circle of the fecond Figure of the
I 14. Scheme^ is a fmall part of the back or under fide of a leaf of Rofemary, which I did not therefore make choice of, becaufe it had any thing peculiar which vya’i not qbfervable with a ^icrofeop^ in -feveral other Plants, but becaufe it exhibits at one view, , * .
Firft, a ftnooth and Ihining furface, nanielyi, A B, ivhich is a part of the upper fide of the leaf, that by a kind of hem or doubling of the leaf ap-= pears on this fide. There are multitudes of leaves, whefe furfaces are like this finooth, and as it were quilted, which look like a curious quilted bagg of green Silk, or like a Bladder, or feme fuch pliable tranfparent fubftance, full ftufed out with a green juice or liquor 5 the furface of Rue, or Herbgrafs, is polifti’d, and all over indented, or pitted, like the Silk-worm’s Egg,which I fhall anon deferibe ^ the fmooth furfaces of other Plants are otherwife quilted, Nature in this, as it were, expreffing her Needle-work, or imbroidery.
Next a downy or bufhy llirface, flich as is all the under fide almofi-, appearing through the Microfeope much like a thicket of bufhes, and with this kind of Down or Hair the leaves and ftalks of multitudes of Vege- tables are covered 5 and there feems to be as great a variety in thefhape, bulk, and manner of the growing of thefe fecundary Plants, as I may call them (they being, as it were, a Plant growing out of a Plant, or fome- what like the hairs of Animals) as there is to be found ambngfi: fmall (hrubs that compofe bufhes 5 but for the moft part, they confift of fmall tranfparent parts, fome of which grow in the fhape of fmall Needles or Bodkins,as on the ThiftlCjCowag-ecod and Nettle 5 others in the form of' Cat’s claws,as in Gliders, the beards of Barley, the edges of feveral forts of Grafs and Reeds,^c. in other,as Coltsfoot, Rofc-campion, Aps, Poplar^ Willow, and almofl: all other downy Plants, they grow in the form of bufhes very much diverfify’d in each particular Plants That which I have
before
ICROGRAHPIA.
before in the 1 9. Obfervation noted on Rofe-leaves, is of a quite difJer- ing kindj and feems indeed a real Vegetable, diftind from the leaf Thirdly, among thefe fmall bufhesaue obfervable an infinite company of fmall round Balls, exadly Globular, and very much referabling Pearls, namely, C C C C, of thefe there may be multitudes obferv’d in Sage, and feveral other Plants, which I fuppofe was the realbn why Athanajius Kircher fuppofed them to be all cover'd with Spiders Eggs, or young Spiders, which indeed is nothing elfe but fome kind of gummous exfii- dation,which is always much of the fame bignefs. At firft fight of thefe,I confefs, I imagin'd that they might have been fome kind of matrices^ ov nourifhing receptacles for fome fmall Infed, juft as I have found Oak- apples, and multitudes of fuch other large excrefcencies on the leaves and other parts of Trees and fhrubs to be for Flyes, and divers other In- leds, but obferving them to be there all the year, and fcarcc at all to change their magnitude, that conjedure feem'd not fb probable. But what ever be the ufe of it, it affords a very pleafant objed through the MicroJcopCy and may, perhaps, upon further examination, prove very luciferous.
Obferv. XXV. Of th jiinging points and juice ^Nettles, and fome other venomous Plants, y
A Nettle is a Plant fo well known to every one, as to what the appear- ance of it is to the naked eye, that it needs no defcription,and there are very few that have not felt as well as feen it ; and therefore it will be no news to tell that a gentle and flight touch of the fkin by a NettIe,does oftentime, not onely create very fenfible and acute pain, much like that of a burn or fcald,but often alfb very angry and hard fwellings and infla- mations of the parts, fuch as will prefently rife, and continue fwoln di- vers hours. Thefe obfervations, I fay, are common enough, but hov/the pain is fo fuddenly created, and by what means continued, augmented fora time, and afterwards diminifh’d, and at length quite exftinguifh'd^ has not, that I know, been explain'd by any.
And here we muft have recourfe to our Mcrofcope^ and that will, if almoft any part of the Plant be looked on, fhew us the whole furface of it very thick fet with turn-Pikes, or fharp Needles, of the fhapeofthofe reprefented in the 1 5. Scheme and firft Figure by A B, which are vifible alfo to the naked eye 5 each of which confifts of two parts very diftind: for fhape.and differing alfb in quality from one another. For the part A, is fhaped very much like a round Bodkin, from B tapering till it end in a very fharp pointy it is of a fubftance very hard and ftif^ exceedingly tranfparent and deer, and, as I by many trials certainly found, is hollow from top to bottom.
This I found by this
Experiment, I had a very convenient Mkra^
M
ICROGRAPHIA
Jcope with a Cngle Glafs which drew about half ah inch.this Ihad faftned into a little frame, almoft like a pair of Speftacles, which I placed before mine eyes, and fo holding the leaf of a Nettle at a convenient diftaticc from my eye, I did firft,with the thrulHng of feveral of thcle briftles into my Ikin, perceive that prefently after I had thruft them in I felt the burn^ ing pain begins next I obferv'd in divers of them, that upon thrufting my finger againft their tops, the Bodkin (if I may fo call it) did not in the leaft bend, but I could perceive moving up and down within it a ccr** tain liquor^ which upon thrufting the Bodkin againft its bafis, or bagg I could perceive to rife towards the top, and upon taking away my hand,
I could fee it again fubfide, and (brink into the bagg 5 this I did very often, and faw this Fh£nomenon as plain as 1 could ever (ee a parcel of water aicend and defeend ina pipe of Glafs. But the ba(K underneath thele Bodkins on which they were faft, were made of a more pliable fubftance, and looked almoft: like a little bagg of green Leather, or rather re(em- bled the (hapeand (urface of a wilde Cucumber, or cucumms and I could plainly perceive them to be certain little baggs, bladders,or receptacles full of water, or as I ghefs, the liquor of the Plant, which wa§ poifonous, and thofe fmall Bodkins were but the Syringe^pipes. or Gly*- fter-pipes, which firft made way into the (kin, and then ferved to convey that poifonous juice,upon the prefiing of thofe little baggs, into the in- terior and fen(ible parts of the (kin, which being fo diicharg d, does cor* rode, or, as it were, burn that part of the (kin it touches 5 and this pain will iometimes laft very long, according as the impreiSion is made deeper or ftrongcr.
The other parts of the leaf or furfaccof the Nettle, have very little confiderable, but what is common to raoft of th^ hinds of Plants, as the ruggedneft or indenting, and hairinels, and other roughneftes ofthelur* face or out-fide of the ft ant, of which I tiiay fey more in another place. As I (hall likewife of certain little pretty clecr Balls or Apples which I have obferved to ftick to the (ides of thefe leaves, both onthe upper and under fide, very much like the (mall Apples which I have often ob(ervd to grow on the leaves of an Oak calfd Oal^^apples which are nothing but the Matricts of an Inlefr, as I eKewherc (hew.
• The chief thing therefore is, how thfe Plant comes, by fo (light a touch, to create fogreat a pain^and the rcafon of this (eems to be nothing eKcjblit the cOrrofive penetrant liquor contain’d in the finall bagg-S Of bladders, upon which grOw out thole (harp Syringe-pipes, as I before noted 5 and very conlbnant to this, is the reafcaii of the paiui created by the ftlng of a Bee, Wa^, ^c, asl eKewherc (hew: For theDart, which is likewile a
pipe, is made a deep paftage into Akin, and then by the anger of thi Fly, is his; gaily poHonous liquor injefted ^ which being admitted among the (enfible parts, aid (b mix’d with the humours or flagn^ifigyxACt^o^. that part,, does create an Ebullitkin perhaps, or effervefeet^y^s is ufually oblerv’d in the mingling of two; dilfeidng Ckyi/Hical faline liq^iOrs, by which means the. parts becolfte fwelfd, hardy and very pahifilllo for tbereby thenervoift’andfosSblefadts-atenotoiniely ftret^^and ftraind
Micrographia.
beyond their natural tone^ but are alfo prick’d, perhaps, or corroded by the pungent and incongruous pores of the intruded liquor.
And this feems to be the reafon, why Aqua fortis, and other falwe li- quorst) if they come to touch the fenfitive parts, as in a cut of the fkin, or the like, do fo violently and intollerably excruciate and torment the Patient. And ’tis not unlikely, but the Inventors of that Diabolical pra- diice of poifoning the points of Arrows and Ponyards, might receive their firfthint from fome (iich Inftance in natural contrivances, as this of the Nettle : for the ground why fuch poifon’d weapons kill lb infallibly as they do, feems no other then this of our Nettle’s ftinging 3 for the Pon- yard or Dart makes a paflage or entrance into the fenfitive or vital parts of the body, whereby the contagious lubftance comes to be diflblv’d by, and mix’d with the fluid parts or humours of the body,and by that means breads it lelf by degrees into the whole liquid part of the body, in the lame manner, as a few grains of Salt,put into a great quantity ofWater, will by degrees diffiile it felf over the whole. i
And this I take to be the realbn of killing of Toads, Frogs, Effi, and fevcral Filhes, by firewing Salt on their backs (which Experiment was ' Ihewn to the Rojial Society by a very ingenious Gentleman, and a worthy Member of it) for thofe creatures having always a continual exludation, as it were,ofllimy and watry parts,fweating out of the pores of their Ikin, the Jalim particles, by that means obtain a vehicle y/vhich conveys them in- to the internal and vital parts of the body.
This feems allb to be the reafon why bathing in Mineral waters arc * foch Ibveraign remedies for multitudes of diftempers,efpccially chronical^ for the liquid 8c warm vehicles of the Mineral particles,which are known to be in very confiderable quantities in thofe healing baths,by the body’s long flay in them, do by degrees fteep and infinuate themlclves into the pores and parts of the lkin,and thereby thole Minera 1 particles have their ways and paflages open’d to penetrate into the inner parts, and mingle themlelves with thcjlagnaut juices of the leveral parts 3 befides,many of | thole offenfive parts which were united with thole fiagnant juices, and j which were contrary to the natural confHtution of the parts, and fo be- come irkfome and painfull to the body, but could not be dilcharged, bc- caule Nature had made no provifion for fuch accidental mifohiefe, are, by |
means of this foaking, and filling the pores of the Ikin with a liquor, a^ forded a paflage through that liquor that fills the pores into the am- bient fluid, and thereby the body comes to be dilcharged.
So that ’tis very evident,there may be a good as well as an evil applica- tion of this Principle. And the ingenious Invention of that Excellent perfon, Doftor IVren^ of injefting liquors into the veins of an Animal, feems to be reducible to this head : I cannot flay, nor is this a fit place, to mention the leveral Experiments made of this kind by the moft incom- parable Mr. Boyle, the multitudes made by the lately mention’d Phyjfciaa \^o€cox,£lark^, the Hiftory whereof, as he has been pleas’d tocommu-* nicate ■ fo the Royal Society, fo he may. perhaps be prevaifd with to make publiquehimlelf; But I fliall rather hint, that certainly, if thistPtincipie
were
Micrograph 1, A*
were well confider’d^there roigbt^ belides the further improving of Bath- ing and Syringing into the veins, be thought on feve.rail ways, whereby feveral obftinate diftempers of a humane body, Inch as the GourjOrophe, Stone, &Q^ might be mafter’d, and expcU’d, and good men might make as good a ufe of it, as evil men have made a perverfe and Diabolicah And that the filling of the pores of the Ikin with feme fiuid ig
of no fmall efficacy towaids the preparing a pafiage for feveral kiads of penetrant juices, and other difibluhle bodies, to infiniiate themfelves within the (kin, and into the fenlitive parts of the body> may be, I think, prov’d by an Infiance given us by in the 26. Chapter of the
fecond Book of his Obfervatuas ^ which containing a very remarkable Story I have here tranferihd : Cuvj Cbam^leonis radices (feys he) apud Vagum quetidam Livadochorio mmcupatum erm curaremtis^ pluvimi Gr£ci Turcce fpe&atumveperunt qnid ermrewusy e^4 fiafiulatim Je- cabantusy filo trapciehamu$ ittfactliw efijtccart pojjent. ‘lHrc£ in eo ne-- gotio occnpatos nos videntesy fimjliter radices pa^are dh fiea.re vqlm^ runt ; at cum jummtss effet ijinSy ensues fudore maderenty qHicunqnq earn radicem manibus tr abd aver ant Jiid&rensque abjierferaiity aut faciem dh gitis Jca/pJeranty tantampruriginent Us lock quQs attigerant pojiea JenJersinty Ht aduri viderentur. Chamcekonis enim xigri radix ea vktute poUet. ut curt ti applicata ipfam adeo inflammety at me Jquil/^y nec urtif£ uUce centejtjn4 parte it a. adurent : At prurigo non adeo (deriter Jefe prodit. Vojl unam ant al- teram perro her am y finguli variis faciei loci 4 cutem adeo infiammatam hat here ciepimus ut tot a fanguinea videretuTy atque quo magis earn cqnfrieaba- muSytanto magis excitabatur prurigo. Fonti ajjldebamus fnb platanOyatque ini- tio pro ludicro habebamm ridebamm : at tandem illi plurimusn indignat f funty njji ajjeverafjemus nunquam expertos tali virtfite earn plant am poller e^
hauddubte male nos multajjent. Attamen nojira excufatiq fujt ab illk facilit w acceptaycum codem incommode nos affeUos conjpicerent. Mirum fane qup4 in tantillo radice tarn ingentem ^caciam mfit'o malo experts fumus.
By which obfervation of his,it leems manilcft,tbat their being all cover’d withfiveat who gather’d and cut this root of the black Chameleon Thifile, was the great reafon why they luffer’d that inconvenience, for it feems the like circuraftance had not been before that noted, nor do I find any men- tion of fuch a property belonging to this Vegetable ip any oftheHer- bals I have at prefent by me*
I could give very many ObferVations which I have made of this kind, whereby I have found that the beft way to get a body to be infinuated into the lubftance or infenfible pores of another, is firft, to find a fluid vehicle that has fome congruity,both to the body to be infinuated, and to the body into whole pores you would have the other convey’d. And in this Principle lies the great myftery of ftaining feveral forts of bodies, as Marble, Woods, Bones, and of Dying Silks, C.loaths, Wools, Fea- thers, (&c. But thefe being digreflions, I lhall proceed to :
Obferv. X X V I. 6^ Co^zgtqcind the itching operation cfJbme boJks^
' I 'Here is a certain Down of a Plant,brought from the EaJi-lndiesyC^lVd ^ Gommonlyj though very improperly, Cowdtchy the reafon of which
X miftake
MiCROGR AP H I A.
miftake ismanifcft enough from the defcription of which Mr. Tarkinfon fetsdownin his Herbal^ Tribe XI. Chap. 2. Vhafiolusjiliquahirjuta 5 The hairy Kiduey-bean, called in Zurratte where itgrows^ Couhage: We have had (fays he) another of this kind brought m out of the Eaft-IndieSj which being planted^ was in Jhew like the former^ but came not to perfe&ion^ the unkindly feafon not fujfering it to few the flower , but of the Cods that were brought^ fomewere jmaller^jhorter^ and rounder then the Garden kind'-y others much longer^ and many growing together ^ as it were in cluflers,iand cover d all over with a brown Jhort hairinefl^fo fi'ne^ that if any of it be rubb’d, or fall on the back^ of ones hand^ or other tender parts of the skin^ it will caufe a kind of itching^ but not firong^ nor long induring^ but pafjing quickly away^ without either danger or harm 5 the Beans were fmaller then ordinary^ and of a black, fining colour.
Having one of thefe Cods given me by a Sea-Captain, who had fre- quented thofe parts, I found it to be a fmall Cod, about three Inches long, much like a Ihort Cod of French Beans^ which had fix Beans in it, the whole furfacc of it was cover’d over with a very thick and Ihining brown Down or Hair, which was very fine, and for its bigncfs ftiff, taking fome of this Down, and rubbing it on the back of my hand, 1 found very little or no trouble, only I was fcnfible that feveral of thefe little downy parts with rubbing did penetrate, and were fenk, orftuck prettyjdeep into my (kin. After I had thus rubb’d it for a pretty while, I felt very little or no pain, in fo much that I doubted, whether it were the true Couhage ^ but whil’ft I was confidering, I found the Down begin to make my hand itch, and in fome places to fmart again^ much like the flinging of a Flea or Gnat, and this continued a pretty while, fo that by degrees I found my Ikin to be fwell’d with little red puftules, an4 to look as if it had been itchie. But luffering it without rubbing or feratch- ing, the itching tickling pain quickly grew languid, and within an hour I felt nothing at all, and the little protuberancies were vanifti’d.
The caufe of which odd Vh^nomenon^ I foppofe to be much the ferae with that of the flinging of a Nettle, for by the Microfeope^ I difcover’d, this Down to confift of a multitude of fmall and (lender conical bodies, much refembling Needles or Bodkins, fuch as are reprefented by A B. CD. E F. of the firft Figure of the XVI. Scheme ^ that their ends AAA, were very (harp, and the ftibflance of them fliff and hard, much like the fubflance of feveral kinds of Thorns and crooks growing on Trees. And though they appear’d very clcer and tranfparent, yet I could not per- ceive whether they were hollow or not, but to me they appear’d like folid tranfparent bodies, without any cavity in them 5 whether, though they might not be a kind of Cane, fill’d with fome tranlpa- rentliquor which was hardned (becaufe the Cod which I had was very dry) I was not able to examine.
Now, being fuch flifl^ ftiarp bodies, it is eafie to conceive, how with rubbing they might eafily be thruft into the tender parts of the skin,and there, W reafon of their exceeding finenefe and drinels, not create any confiderable trouble or pain, till by remaining in thofe places moiftned with the humours of the body, feme cauftick part flicking cn them, or
refiding
Micrographia.
redding within them might be diflblv'd and mix’d with the ambient juices of that place, and thereby t)io(c fibres and tender parts adjoyning be- come afieded, and as it were corroded by it 5 whence, while that adi- on lafts, the pains created are pretty (harp and pungent, though (mall, which is the eflential property of an itching one;
That the pain alfo caufed by the (tinging of a Flea, a Gnat, a Flie, a Wafp, and the like, proceeds much from the very fame caufe, I ehewhere in their proper places endeavour to manifefl:. The (tinging alfo of (hred Horf-hair, which in meriment is often ftrew’d between the (heets of a Bed^ (eems to proceed from the (ame cau(e;
Obferv. X X V 1 1. Of the Beard of a mlde Oat, and the ufe that may he made of it for ed>ibiting always to the Eye the temperature of the Air^ as todrinefi and moijhre,
THis Beard of a wild Oat^ is a body of a very curious (trudure,though to the naked Eye it appears very (light, and inconfiderable, it being only afmall black or brown Beard or Bri(tle,which grows out of the (ide of the inner Husk that covers the Grain of a wild O^t^the whole length of it,when put in Water, fo that it may extend it felf to its full length,is not above an Inch and a half,andfor the moft part (biiiewhat (horter,but when the Grain is ripe, and very dry, which is ufualy in the Moneths of and Augujl^ this Beard is bent fome what below the middle, namely ,about f from the bottom of it, almoft to a right Angle, and the under part of it is wreath’d lik a With ^ the fubftance of it is very brittle when dry, and it will very eafily be broken from the husk on which it grows.
If you take one of thefe GrainSj and wet the Beard in Water,you will prefently fee the (mall bended top to turn and move round, as if it were fenlible, and by degrees, if it be continued wet enough, the joint or knee: will ftreighten it felf, and if it be fuffer’d to dry again, it will by degrees move round another way, and at length bend again into its former pofturc.
Ifitbeview’d with an ordinary (ingle Mkrofeope^ it 'will appear like a (mall wreath’d Sprig, with two clefts ^ and if wet as before, and then look'd on with this Microfeepe^ it will appear to unwreath it felf^ and by degrees,to ftreighten its knee, and the two clefts will become ftreight, and almoft on oppofite (ides of the (mall cylindrical body.
If it be continued to be look’d a little longer with a Microfeope^ it will within a little while begin to wreath it (elf again, and foon after return to its former pofture, bending itielf again neer the middle, into a kind of knee or angle.
Several of thole bodies I examin’d with larger Mkrojeopes, and there found them much of the make ofthofe two long wreath’d cylinders de- lineated in the lecond Figure of the 1 5. scheme^ which two cylinders re-
X 2 prelent
Micrographia.
prefent the wreathed part broken into two pieces,whereof the end A B is to be luppos’d to have join’d to the end C Dj lb that E A C F does repre- fent the whole wreath'd part of the Beard, and E G a fmall piece of the upper part of the Beard which is beyond the knee, which as I had not room to’infert, lb was it not very confiderable, either for its fbrm,or any known property 5 but the under or wreathed part is notable for both ; AstoitsTorm, it appear’d, ifit were look’d on fide-ways, almoftlikea Willow, or a fmall tapering rod of Hazel^ the lower or bigger half of which onely, is twifted round leveral times,in fome three, in others more, in others lels, according to the bignefs and maturity of the Grain on which it grew, and according to the drinefs and moifturc of the ambient Air, as I lhall Ihew more at large by and by.
The whole outward Superficies of this Cylindrical body is curioufly adorned or fluted with little channels, and interjacent ridges, or little protuberances between them, which run the whole length of the Beard, and are ftrdght where the Beard is not twifced,and wreath’d where it is, juft after the lame manner ; each of thole fidcs is befet pretty thick with i fmall Brilles or Thorns, Ibmewhat in form refembling that of Porcupines Qifills, fuch lis a aaaa in the Figure 5 all whofe points are direded like fomany Turn-pikes towards the fmall end or top of the Beard, which is therealbn, why, if you endeavour to draw the Beard between your fin- gers the contrary way, you will find it to ftick, and grate, as it were, againft the fkin.
The proportion of thele Imall conical bodies aaaaa to that whereon they grow, the Figure will liifficiently Ihew, as alfo their manner of grow- ing,their thicknefs, and neerncls to each other, as, that towards the root or bottom of the Beard, they are more thin, and much lhorter,inlbmuch that there is ufually left between the top of the one, and the bottom of that next above it, more then the length of one of them, and that to- wards the top of the Beard they grow more thick and clofe (though there be fewer ridges) lb that the root, and almoft half the upper are hid by the tops of thole next below them.
I could not perceive any tranjverje pores, unlefs the whole wreath’d part were leparated and cleft,in thofe little channels,by the wreathing in- to fo many little ftrings as there were ridges, which was very difficult to determine , but there were in the wreathed part two very conlpkUOus channels or clefts, which were continued from the bottom F to the el- bow E H, or all along the part which was wreath’d, which (eem'dto di- vide the wreath’d Cylinder into two parts, a bigger and a lels ^ the bigger was that which was at the conT/ex iide of the knee, namely, on the fide A, and was wreath’d by O O O O O 5 this, as it leem d the broader, lb did it alfo the longer, the other P P P P P, which was ulually purs’d or wrinckled in the bending of the knee,as about E, feem’d both the Ihorter and narrower, fo that at firft I thought the wreathing and unwreathing of the Beard might have been caus’d by the Ihrinking orfwelling of that part 5 but upon further examination,! found that the clefts, K K, L L,werfe ftuft up with a kind of Spongic fubftance, which, for the moft part, was
very
Micrograph! A.
very confpicuous neer the knee^ as in the cleft K Kj when the Beard was dry 5 upon the difcovery of which. I began to think, that it was upon the fwellingof this porous pith upon the accefs of moifture or water that the Beard, being made longer in the mid ft, Was ftreightned.and by the ftirink- ing or lubftding of the parts of that Spongie fubftance together, when the water or moifture was exhal’d or dried, the pith or middle parts growing fhorter, the whole became twifted.
• But this I cannot be pofitive in, for upon cutting the wreath’d part in many places tranfverlly, I was not fo Well fatisfy’d with theftiape and manner of the pores of the pith for looking on thefe tranfverfe Seftrions with a very good Microfivpej I found that the ends of thofe tranf- verfe Setftions appear’d much of the manner of the third Figure of the
Scheme ABCFE, and the middle or pith CC, feem’d very full of pores indeed, but all of them feem’d to run the long-ways.
1 his Figure plainly enough (hews in what manner thofe clefts, K and L, divided the wreath’d Cylinder into two unequal parts, and alfb of what kind of fubftance the whole body confifts 5 for by cutting the fame Beard in many places, with tranfverfq Sediions, I found much the fame ap- pearance with this exprefs’d 5 fo that thofe pores foem to run, as in moft: other fuch Cany bodies, the whole length of it.
The clefts of this body KK, and LL, feem’d (as is alio exprefs'd in the Figure) to wind very oddly in the inner part of the wreath 5 and in fome parts of them, they feem’d fluffed, as it vvere,with that Spongie fubftance, which I juft now defcribed.
This fo oddly conftituted Vegetable fobftance, is firft (that I have met with) taken notice of by Porta^ \n\\\s'Nattiral M^gick^^ as a
thing known to children and Juglers, and it has been call’d by fome of thofe laft named perfons, the better to cover their cheat, the Legg of ail Arabian spider an inchanted Egyptian Fly ^ and has been ufcd by them to make a finall Index, Crofs, or the like, to move round upon the wetting of it with a drop of Water, and muttering certain words.
But the ufe that has been made of it, for the difcovery of the various conftitutions of the Air, as to drinefs and moiftnefs, is incomparably beyond any other , for this it does to admiration : The manner of con- triving it fb, as to perform this great effed, is oncly thus :
Provide a good large Box of Ivory, about four Inches over, and of what depth you (hall judge convenient (according to your intention of making ufe of one, two,three,or more of thefe fmall Beards, ordered in the manner which I fhall by and by defcribe)let all the fides of this Box be turned of Bafket-work (which here in Londok is eafily enough procur’d) full of holesjin the manner almoft of a Lettice, the bigger, of more the holes are,the better, that fo the Air may have the more free pallage to the inclofed Beard, and may the more eafily pafs through the Ififtruraent ; it will be better yet, though not altogether fo handfom,if infteed of the Baf- ket-work on the ftdes of the Box, the bottom and top of the Box be join’d together ondy with three or four fmall Pillars, after the manner reprc-
fentcd
1^0 M I C R O G R A P H I A.
fented in the 4-Figure of the 1 5. Scheme. Or,if you intend to make ufe of many of thefe fmall Beards join'd together, you may have a finall long Cafe of Ivory, whofe fides are turn’d of Bafket-work, full of holes, which may be ferew’d on to the underfide of a broad Plate of Ivory ,on the other iidc of which is to be made the divided Ring or Circle, to which divifi- ons the pointing of the Hand or Index, which is moved by the conjoin’d Beard, may (hew all the Minute variations of the Air.
There may be multitudes of other ways for contriving this Imall Inferu- ment, fo as to produce this effed, which any one may, according to his peculiar ufe, and the exigency of his prefent occafion, eafily enough con- trive and take, on which I (hall not therefore infift. The whole manner of making any one of them is thus : Having your Box or frame A A B B, fitly adapted for the free paflage of the Air through ir,in the midft of the bot- tom B B B, you mufthave a very fmall hole C, into which the lower end of the Beard is to be fi xd,the upper end of which Beard a. I? As to pals through a fmall hole of a Plate, or top A A, if you make ufe onely of a fingle one, and on the top of it e, is to be fix’d a fmall and very light Index fg^ made of a very thin (liver of a Reed or Cane 5 but if you make ufe of two or more Beards, they muft be fix’d and bound together, either with a very fine piece of Silk, or with a very fmall touch of hard Wax, or Clew, which is better, and the Index fg^ is to be fix’d on the top of the fecond, third, or fourth in the fame manner as on the fingle one.
Now,becaufe that in every of thefe contrivances, the Index fg^ will with (bme temperatures of Air, move two, three, or more times round^ which without fome other contrivance then this, will be difficult to difein- gui(h,thcrefore I thought of this Expedient : The Index or Handfg, be- ing rais’d a pretty way above the furface of the Plate A A, fix in at a little diftance from the middle of it a fmall Pin fo as almoft to touch the (urfacc of the Plate A A, and then in any convenient place of the furface of the Plate,fix a (mall Pin, on which put on a fmall piece of Paper, or thin Paft-board, Vellom, or Parchment, made of a convenient cize, and (hapr’d in the manner of that in the Figure exprefs’d by / 4, fo that having a convenient number of teeth every turn or return of the Pin may move this (mall indented Circle, a tooth forward or back- wards, by which means the teeth of the Circle, being mark’d, it will be thereby very eafie to know certainly, how much variation any change of weather will make upon the fmall wreath’d body. In the making of this Sccundary Circle of Vellom, or the like, great care is to be had, that it be made exceeding light, and to move very eafily, for otherwife a (mall variation will (poll the whole operation. The Box may be made of Brals, Silver, Iron, or any other fubftance, if care be taken to make it open enough, to let the Air have a fufficiently free accels to the Beard. The Index alfo may be various ways contrived, fo as to (hew both the number of the revolutions it makes, and the Minute divifions of each revolution.
I have made feveral trials and Inftruments for difeovering the drinels and moifture of the Air with this little wreath’d body, and find it to vary exceeding fenfibly with the leaft change in thcconftitutioD4Df the Air, as
to
Mi C R O G R A P H I A. I^I
to drinefs and moiftut*ei, lb that with one breathing upon it j I haVe madd it untwift a whole bout, and the Index or Hand has fliew’d or pointed to various divifions on the upper Face or Ring of the Inftrument, according as it was carried neerer and neerer to the fire, or as the heat of the Sun increafed upon it.
Other trials'I have made with Gut'ftrings,but find them nothing ncer. fo fcnfible, though they alfo may be fo contriv’d as to exhibit the changes of the Air, as to drinefs and moifture, both by their ftretching and thrinking in length, and alfo by their wreathing and unwreathing themfelves 5 but thefe are nothing neer fo exad or fo tender,for their va- rying property will in a little time change very much. But there are fe^ verai other Vegetable fubftances that are much more fonfiblethen even this Beard of a wilde fiich I have found the Beard ofthefecd of Mulh-gralsj or Geranium mofehatum^ and thofo of other kinds of Cranes-r bil feeds, and the like. But always the final ler the wreathing fubfiance be, the more fenfible is it of the mutations of the Air, a conjefture at thereafon of which I (hall by and by add.
The lower end of this wreath’d Cylinder being ftuck upright in a little foft Wax, fo that the bended part or Index of it lay herizontalj I have obferv.’d it always with moifture to unwreath it felf from the Eaft (For inftance)by the South to the Weli,and foby the North to the Eaft again, moving with the Sun (as we commonly fey) and with heat and drouth to re-twift, and wreath it felf the contrary way, namely, fropi the Eaft,
(for inftance) by the North to the Weft, and fo onwards* '
The caufe of all which Vh<cnomena^ feems to be the differing lexfurc of the parts of thefe bodies, each of them (clpecially the Beard of a wilde Oat^ and of Mesk-grajs feed J feeming to have two kind of lubftances,one that is very porous.loofe,and fpongic,into which the watry Iteams of the Air may be very eafily forcedjWhich will be thereby fwell’d and extend- ed in its dimenfions^ juft as we may obferve all kind of Vegetable fub- ftanceupon fteeping in water to fwell and grow bigger and longer. And a fecond that is more hard and dofe,into which the water can very little,or not at all penetrate, this therefore retaining always very neer the feme dimenfions, and the other ftretching and fhrinking, according as there is more or lefs moifture or water in its pores, by reafon of the make and (hape of the parts , the whole body muft neceflarily unwreath and wreath it felf
And upon this Principle, it is very eafie to make feveral forts of con- trivances that ftiould thus wreath and unwreath themfelves, either by heat and cold, or by drinefe and moifture, or by any greater or lefs force, from whatever caufe it proceed, whether from gravity or weight, or from wind which is motion of the Air, or from fome Ipringing body, or the like.
This, had I time, I ftiould enlarge much more upon 5 for it feems to me to be the very firft footftep of Senfation^ and Animate motion, the moft plain,fimple,and obvious contrivance that Nature has made ufe of to pro^ duce a motion, next to that of Rarefadtion and Condenfation by heat
and
Micrograhpia.
and cold. And were thisPrinciple very well examin d, I am very apt to think, it would afford us a very great help to find out the Mechamfm of the Mufcles, which indeed,as farr as I have hitherto been able to ex- amine, Teems to me not fo very perplex as one might imagine, cfpecially upon the examination which I made of the Mufcles of Crabs^Labfitrs^ziid feveral forts of large Sheli-fifh,and comparing my Obfervations on tkem, with the circumftances I obferv’d in the mufcles of terreftrial Animals.
Now^^as in thisinftance of the Beard of a wilde Oat^ we fee there is nothing elfe requifite to make it wreath and unwreath it felf^ and to ftreighten and bend its knee, then onely a little breath of moift or dry Air, or a fmall atome alrnofl of water or liquor, and a little heat to make it again evaporate j for, by holding this Beard, plac’d and fix’d as I be- fore direded, neer a Fire, and dipping the tip of a final! fhred of Paper ki well redfify’^d fpirit of Wine, and then touching the wreath’d Cylin- drical part,you may perceive it to untwifi: it felf 5 and prefently again,up- on the avolation of the fpirit, by the great heat, it will re-twiff it felf, and thus will it move forward and backwards as oft as you repeat the touching it with the fpirit of Wine , fo may, perhaps, the fhrinking and relaxing of the mufcles be by the influx and evaporation of fome kind of liquor or juice. But of this Enquiry I fhall add more elfewhere.
Oblerv. XXVIII. Of the Seeds 0/ Venus lookjng-glajl^ or Corn Violet.
FRom the Leaves, and Downs, and Beards of Plants,we come at laftto the Seeds ^ and here indeed feems to be the Cabinet of Nature, where- in are laid up its Jewels. The providence of Nature about Vegetables,is in no part manifefted more, then in the various contrivances about the feed, nor indeed is there in any part of the Vegetable fb curious carvings, and beautiful 1 adornments, as about the feed 5 this in the larger forts of feeds is moft evident to the eye 5 nor is it lefs manifefi: through the Microjeope^ in thofe feeds whofe fhape and ftrufture, by reafon of their fmalnefi, the eye is hardly able to diftinguilh.
Of thefe there are multitudes, many of which I have obferv’d through a Microfeope, and find, that they do, for the moft part, every one afford exceeding pleafant and beautifull objeds. For befidcs thofe that have various kinds of carv’d furfaces, there are other that have fmooth and perfcftly polifh’d furfaces, others a downy hairy furface, fome are cover’d onely with a fkin, others with a kind of fhell, others with both, as is obfervable alfo in greater feeds.
Of thefe feeds I have onely deferibed four forts which may ferveas a Specimen of what the inquifitive obfervers are likely to find among the reft. Thefirft of thefe feeds which are deferibed in the Scheme, are thofe of Corn-Violets, the feed is very fmall, black, and fhining, and, to the naked eye, looks almoft like a very fmall Flea, But through the
Microfeope
SchetmoQvii .
;
: m Si III
I
Micrograpmia.
Mk rofcope^ it appears a large body, cover’d with a tough thick and bright rcflcfting Ikin very irregularly fhrunk and pitted, infomuch thatitisal- moft an inrpoffibility to find two of them wrinkled alike, fo great a va- riety may there be even in this little feed.
Hi This, though it appear’d one of the moft promifing feeds for beauty to the naked eye,yet through the Murofiope it appear’d but a rude milhapen feed, which I therefore drew, that I might thereby manifeft how unable we are by the naked eye to judge of beauteous or left curious mkrofcopi- ^■^/Obje&s 5 cutting feme of them in funder, I obferv’d them to be fill’d with a greenifh yellow pulp, and to have a very thick hulk, in propor- tion to the pulp*
Obferv. XXIX. Of the Seeds me,
THefe pretty fruits here reprefented, in the i8. Scheme^ are nothing elfe,but nine feveral feeds of Tyme ^ they are all of them in differ- ing pofture,both as to the eye and the light , nor are they all of them ex- actly of the fame ftiape, there being a great variety both in the bulk and figure of each feed ^ but they all agreed in this,that being look’d on with a Microfcope^ they each of them exadly refembled a Lemmon or Orange dry’d 5 and this both in fhape and colour. Some of them are a little rounder, of the fhape of an Orange, as A and B, they have each of them a very confpicuous part by which they were join’d to their little ftalk,and one of them had a little piece of ftalk remaining on 5 the oppo- fitefideof the feed, you may perceive very plainly by the Figure,is very copped and prominent, as is very ufeal in Lemmons, which prominencies are exprefs’d in D, E and F. ;
They feem’d each of them a little creas’d or W'rinckled, but E was very confpicuoufly furrow’d, as if the inward make of this feed had been fomewhat like that of a Lemmon alfo, but upon dividing feveral feeds with a very fharp Pen-knife, and examining them afterv/ard, I found their make to be in nothing but bulk differing from that of Peas^that is,to have a pretty thick coat, and all the reft an indifferent white pulp, which fcem d very clofe 5 fb that it fecms Nature does not very much alter her method in the manner of inclofing and preferving the vital Principle in the feed, in thefe very frnall grains, from that of Beans, Peas,
The Grain affords a very pretty Objed for the JUficrofiope^ namely, a Difhof Lemmons plac’d in a very little room 5 fhould a Lemmon or Nut be proportionably magnify ’d to what this feed of Tyme is,it would make it appear as bigg as a lalrge Hay-reek,and it would be no great wonder to fee Homers Iliads^ and Homer and all, cramm’d into fuch a Nut-fhell. We may perceive even in thefe fmall Grains, as well as in greater, how curi- ous and carefull Nature is in preferving the feminal principle of Vege- table bodies, in what delicate, ftrong and moft convenient Cabinets fhe
Y lays
Micrographi a.
lays them and doles them in a pulp for their fa ferprotedion from out- ward dangers, and for the fupply of convenient alimental juice, when the heat of the Sun begins to animate and move thefe little antomatont or Engines , as iffhe would,from the ornaments wherewith (he has deckf thele Cabinets, hint to us, that in them fhe has laid up her Jewels and Mafter-pieces. And this, if we are but diligent in obferving, we fliall find her method throughout. There is no curiofity in the Elemental kingdom, if I may fo call the bodies of Air, Water, Earth, that are com- parable in form to thole of Minerals^ Air and Water having no format all, unlels a potentiality to be form’d into Globules 3 and the clods and parcels of Earth are all irregular, whereas in Minerals Ihe does begin to Geometrize^ and pradife, as ’twere, the firft principles oi Mschanicki^ fhaping them of plain regular figures, as triangles, Iquares, and U- traeclrons^ cubes, But none of their forms are comparable to the more compounded onesof Vegetables 5 For here Ihe goes a Hep further, forming them both of more complicated fliapes, and adding alfo multi- tudes of curious Mechanick contrivances in their ftrudure^for whereas in Vegetables there was no determinate number of the leaves or branches, nor no exadly certain figure of leaves, or flowers,or leeds, in Animals all thole things are exadly defin’d and determin’d 3 and whcre-ever there is either an excels or dcfed of thole determinate parts or limbs,there has been Ibme impediment that has fpoil’d the principle which was raoft re- gular : Here we lhall find, not onely molf curioully compounded lhapes, but moll: ftupendious Mechanifms and^contrivances, here the ornaments arc in the higheft perfedion, nothing in all the Vegetable kingdom that is comparable to the deckings of a Peacock 5 nay,to the curiofity of any feather, as I elfewhere Ihew ^ nor to that of the Imalleft and molf delpi- cable Fly. But I mulf not Ifay on thefe (peculations, though perhaps it were very well worth while for one that had leilure,to fee what Informa- tion may be learn’d of the nature,or ufe,or virtues of bodies,by their Icve- ral forms and various excellencies and properties. Who knows but Adam might fromfome liich contemplation, give names to all creatures? If at lealt his names had any fignificancy in them of the creature’s nature on which he impos’d it 3 as many (upon what grounds I know not) have llippos’d : And who knows, but the Creator may,in thofe charaders,havc written and engraven many of his raoft myfterious defigns and counfels, and given man a capacity, which, aftifted with diligence and induftry, may be able to read and underftand them. But not to multiply my di- greffion more then I can the time5 1 will proceed to the next, which is.
Obferv. XXX. Of the Seeds
THe Imall leeds of Poppy, which are delcribed in the 19. Scheme^hoth for their Imalncls, multiplicity and prcttinels, as alfo for their ad- mirable foporifick quality, deferve to be taken notice of among the
other
Schem:XlX
M
ICROGRAPHlAi
Other microjcopkal feeds of Vegetables : For firft, though they grow in a Cafe or Hive oftentimes bigger then one of thefe Figures of the mfcra- fc epical appearance, yet are they for the moft part fo very little, that they exceed not the buIkbfafmallNkt,being not above part of an Inch in
Diameter, whereas the Diameter of the Hive of them oftentimes exceeds two Inches,!© that it is capable of containing necr two hundred thoufend, and fo in all likelihood does contain a vaft quantity, though perhaps not that number. Next, for their prettinefs, they may be compar'd to any microfcopical feed I have yet feen 5 for they are of a dark brownifh red colour, curioufly Honey-eomb'd all over with a very pretty variety of Net’Work, or a fmall kind ofimboknent of very orderly rak'd ridges the ferface of them looking not unlike the infide of a Beev'sftomack. But that which makes it moft confiderable of all, is, the medicinal virtues of it, which are fuch as are not afforded m by any Mineral preparation 3 and, that is for the procuring of fleep, a thing as necefi^y to the well-being of a creature as his meat, and that which refrelhes both the voluntary and rational faculties, which, whil'd this affodion has feis'd the body,are for the moft part unmov'd, and at reft. And, methinks. Nature does feera to hint fome very notable virtue or excellency in this Plant from the curiofity it has beftow'd upon it. Firft, in its flower, it is of the higheft fearlet-Dye, which is indeed the prime and chiefeft colour, and has been in all Ages of the world moft highly efteem'd : Next, it has as much cu- rioflty Ihew'd alfo in the hulk or cafe of the feed, as' any one Plant I have yet met withall 5 and thirdly, the very feeds themfelves, the jWerofiope difeovers to be very curioufly fhap'd bodies 3 and laftly. Nature has taken luch abundant care for the propagation of it, that one Angle feed grown into a Plant, is capable of bringing fome hundred thoufends of feeds.
It were very worthy fome able matins enquiry whether the intention of Nature, as to the fecundary end of Animal and Vegetable- fobftances might not be found out by fome Itich characters and notable impreflions as thefe, or from divers other circuniftances, as the figure, colour, place, time of flourifhing, Ipringing and fading, duration, tafte, fmcll, For if foch there are (as an able Pf^Jicidn upon good grounds has given me caufe to believe) we might then, infteed of ftudying Herbals (where fo little is deliver d of'the virtues of a Plant, and left of truth) have re- courfe to the Book of Nature it felf, and there find the moft natural, ufefull, and moft effectual and fjDecifick Medicines, of which we have, amongft Vegetables, two very noble Inftances toincOurage filch' a hope, the one of the Jejitite poTpder for the cure of intermitting Fe4®-ei%and the other of the juice of Poppy for the curing the defed of fleeping.
1^6 Micrographia.
Obferv. XXXI. <?/ Puiflane-feed.
THc Seeds of Vurjlane feem of very notable fhapes, appearing through the Microjcepe fliap’d Ibmewhat like a nautilus or Porcelanc fliellj as may be feen in the XX. Scheme^ it being a finall bodys coyfd round in the manner of a Spiral , at the greater end whereof, which reprefents the mouth or orifice of the Shell, there is left a little white tranl^arent fob- ftance, like a Ikin, reprefented by B B B B, which Teems to have been the place whcrcunto the ftem was join'd. The whole forface of this Coclea or Shell, is cover’d over with abundance of little prominencies or buttons very orderly rang’d into Spiral rows, the fhapcof each of which feem’d much to rcfcmble a Wart upon a mans hand. The order, variety, and curiofity in the lhape of this little feed, makes it a very pleafant objedl: for the Microjcope, one of them being cut afonder with a very (harp Pen- knife, difcover d this carved Cafket to be of a brownifh red, and fome- what tranlparent fobftance, and manifefted the infide to be fill’d with a whitifh green fobftance or pulp, the Bed wherein the leminal principle lies invelop'd.
There are multitudes of other feeds which in fhape reprefent or imi- tate the forms of divers other forts of Shells ; as the feed of Scurvy^ graJSj very much refembjes the make of a Concha Venerea^z kind of Purce- lane Shell 5 others reprefent fcveral forts of larger fruits, fweat Marje- rome and Pot-marjerome reprefent Olives. Garret feeds are like a cleft of a Coco-Nut Hufk 5 others are like Artificial things, as Succory feeds are like a Quiver full of Arrows, the feeds of Amaranthus are of an ex- ceeding lovely fhape, fomewhat like an Eye : The fkin of the black and fhrivled feeds of Onyons and Leeks,arc all over knobbed like a Seals fkin. Sorrel has a pretty black ihining three-fquare feed, which is picked at both ends with three ridges, that are bent the whole length of it. It were al- moft endleft to reckon up the feveral fhapes,thcy are fo many and fo va- rious ^ Leaving them therefore to the curious obferver, I fhall proceed to theObfervations on the parts of Animals.
Obferv. XXXII. \0f the Figure of feveral forts cf Hair, and of the texture of the (kin,
Viewing fome of the Hairs of my Head with a very good Microjeope^ I took notice of thefe particulars ;
I. That they were, for the moft part. Cylindrical^ fome of them were fomewhat Pr^matical^hut generally they were veryneer round,foch as are reprefented in the fccond Figure of the <^.Schem9}^j the Cylinders E E E. nor could 1 find any that had fharp angules.
2. That
SchoTV.XX.
MiCROGRAPHlA.
2. Th^t that part which Was next the top. Was bigger then that which was neerer the root.
gi. That they were all along from end to end traniparent, though not very deer, the end next the root appearing like a black tranfparent piece of Horn, the end next the top more brown, fomewhat like tranfparent Horn.
4. That the root of the Hairs were pretty fmooth, tapering inwards, almoft like a Parfneb, nor could I find that it had any filaments, or any other veflels, fuch as the fibres of Plants.
5. That the top when fplit (which is common in long Hair) appear’d like the end of a ftick, beaten till it be all flitter’d, there being not onely two fplinters, but fometimes half a fcore and riiotei
6. That they were all, as farr as I was able to find, fblid Cylindrical bodies, not pervious, like a Cane or Bulrufh 5 nor could I find that they had any Pith, or diffinffion of Rind, or the like, fuch as I had obferv’d iri Horfe-hairs, the Briftles of a Car, the Indian Deer’s Hair,
Obfervatiom on fever al other forts cfBdlr,
For theBrifles of a Hogg, I found them to be firfl: a hard tranfparent horny fubftance, without the leafi: appearance of pores or holes in it 5 and this I try’d with the greatefi: care I was able, cutting many of them with a Very (harp Razor, fb that they appear’d, even in the Glals, to have a pret- ty finooth furface, but fomewhat waved by the fawing to and fro of the Razor, as is vifible in the end of the Prifmatical body A of the fame Figure , and then making trials with caufing the light to be caft on them all the various ways I could think of, that was likely to make the pores appear, if there had been any, I was not able to difoover any.
Next, the Figure of the Brifles was very various, neither perfectly round, nor fharp edg’d, but Prifmatical^ with divers fides, and round, angles, as appears in the Figure A. The bending of them in any part where they before appear’d deer, would all flaw them, and make them look white.
The_^MuftacheosofaCat (part of one of which is reprefented by the fhort Cylinder B of the fame Figure) feem’d to have, all of them that I ob- ferv’d,a large pith in the middle, like the pith of an Elder, whole texture was fo dole, that I was not able to difoover the leafi: lign of pores j and thole parts which foem to be pores, as they appear’d in one pofition to the light, in another I could find a manifefi reflediom to be caft from them.
This I inftance in,to hint that it is not fafe to conclude any thing to be pofitively this or that, though it appear never fo plain and likely when look’d on with a Microfeofe in one pofturej before the fame be examin’d by placing it in fcveral other pofitions*
And this I take to be the reafon why many have believed and afidted the Hairs of a man’s head to be hollow, and like fo many fmall pipes per- forated from end to end.
Now, though I grant that by an Analogie one may fuppofe them fo,
and
Micrograhpia.
and from the Volonian difeafe one may believe them fuch^ yet I think wc have not the leaft encouragement to either from the MtcrofeopCy much lels pofitively to aflert them fuch. And perhaps the very eflence of the Plied Pohnica may be the hairs growing hollow, and of an unnatural con- ftitution.
And as for the Analogic^ though I am apt enough to think that the hairs of leveral Animals may be perforated Ibmewhat like a Cane, or at lead: have a kind of pith in them,firll:,becaufe they feem as ’twere a kind of Ve- getable growing on an Animal, which growing, they lay, remains a long while after the Animal is dead, and therefore Ihould like other Vege- tables have a pith 5 and fecondly, becaufc Horns and Feathers, and Por- cupine’s Quils, and Cats Brilles, and the long hairs of Horfes, which come very neer the nature ofa mans hair,feem all of them to have a kind of pith, and Ibmc of them to be porous,yet I think it not (in thele cafes,where we have luch helps for the lenle as the Microjeope affords) fafe concluding or building on more then we fenfibly know, fince we may, with exami- ning, find that Nature does in the make of the fame kind of fubftance, often vary her method in framing of it : Inftances enough to confirm this we may find in the Horns of feveral creatures : as what a vaft difference is there between the Horns of an Oxe,and thofe of Ibme forts of Staggs as to their fhape ? and even in the hairs of feveral creatures, we find a vaft difference 5 as the hair of a man’s head feems, as I faid before, long. Cylindrical and fometime a little Prifmatical^ folid or impervious, and very fmall , the hair of an Indian Deer (a part of the middle of which is delcribed in the third Figure of the fifth Scheme^ marked with F) is big- ger in compals through all the middle of it,then the Brille of an Hogg,but the end of it is fmaller then the hair of any kind of Animal (as may be leen by the Figure G) the whole belly of it, which is about two or three Inches long, looks to the eye like a thread of courle Canvals, that has been newly unwreath’d, it being all wav’d or bended to and fro, much after that manner, but through the Microfeope, it appears all perforated from fide to fide,and Spongie,like a fmall kind offpongy Coral, which is often found upon the Englijh {horts'-) but though I cut it tranfverfly, I could not perceive that it had any pores that ran the long-way of the hair ; the long hairs of Horles C C and D, feem Cylindrical fomewhat pithy 5 the Brilles of a Cat B, arc conical and pithy: the Quils of Por- cupines and Hedghoggs, being cut tranfverlly, have a whitifb pith, in the manner of a Starr,or Spur-rowel ; Piggs-hair (fA) is Ibmewhat triagonal^ and feems to have neither pith nor pore : And other kinds of hair have quite a differing ftrudture and form. And therefore I think it no way agreeable to a true natural Hiftorian, to pretend to be fo lharp-fighted, as to lee what a pre-eonceiv’d Hypothejis tells them ffiould be there,where another man, though perhaps as feeing, but not foreftall’d, can dilcover no lUch matter.
But to proceed 5 I oblerv’d feveral kind of hairs that had been Dyed, and found them to be a kind of horny Cylinder^ being of much about the tranfparency of a pretty deer piece of Oxe horn 3 thefe appear’d quite
through-
MiCROGRAPHiA;
throiighoi t ting'd with the colours they exhibited. And 'tis likely^that thofe hairs being boy Td orfteep'din thofe very hot ting’d liquors in the D)- e-fat. And the fubftance of the hair being much like that of an Oxes Horn, the penetrant liquor docs lo far mollifie and foften the fubftance, that it finks into the very center, of it, and fo the ting d parts come to be mix’d and united with the very body of the hair, and do not (as fome have thought) only flick on upon the outward furface. And this,the boiling of Horn will make more probable 5 for we fhall hnd by that action, that the water will infinuate it felf to a pretty depth within the furface of it, efpecially ifthis penetrancy of the water be much helped by the Salts that areufually mix’d with the Dying liquors. Now. whereas Silk may be dyed or ting’d into all kind of colours without boiling or dipping in- to hot liquors, I ghefs the reafon to be two-fold : Firft:, becaufe the fila- ments, or fmall cylinders of Silk, are abundantly fmaller and finer, and fo have a much Ids depth to be penetrated theri moft kind of hairs , and next, bccaufe the fubftance or matter of Silkj is much more like aGlew then the fubftance of Hair is. And that I have reafon to fuppofo: Firft, becaufe when it is fpun or drawn out of the Worfii, it is a perfect glutinous fubftance, and very eafily flicks and cleaves to any adjacent bod y, as I have feveral times obferved, both in Silk-worms and Spiders. Next, becaufe that I find that water does eafily diftblve and mollifie the fiibftance again, which is evident from their manner of ordering thofo bottoms or pods of the Silk-worm before they are able to unwind them. It is no great wonder therefore,if thofoDyes or ting’d liquors do very quick- ly mollifie and tinge the furfaces of fo fmall and fo glutinous a body. And we need not wonder that the colours appear fo lovely in the one, and fo dull in the other, if we view but the ting’d cyliuders of both kinds with a good Microfeope , for whereas the fubftance of Hair, at beft,is but a dirty dufkifh white fomewhat tranfparent, the filaments of Silk have a moft lovely tranfparency and cleernefs, the difference between thofo two being not much left then that between a piece of Horn, and a piece of Cryftd 5 the one yielding a bright and vivid refledion from the con- cave fide of the cylinder, that is, from the concave furface of the Air that incompafles the back-part of the cylitider , the other yielding a dull and perturb’d refledion from the feveral Heterogeneous parts that com- pofe it. And this difference will be manifeft enough to the eye, if you get a couple of fmall Cylinders, the fmaller of Cryftal Glafs,the other of Horn, and then varnifhing them over vety thinly with fome tranfparent colour, which will reprefent to the naked eye much the fame kind of objed which is reprefented to it from the filaments of Silk and Hair by the help of the Microjeope. Now,fincethe threads of Silk and Serge are made up of a great number of thefo filaments, we may henceforth ceafe to wonder at the difference. From much the fame reafon proceeds the vivid and love- ly coloursofFeathers, wherein they very farr exceed the natural as well as Artificial colours of hair, of which I fhall fay more in its proper place.
The Teguments indeed of creatures are all of them adapted to the pe*- suliar ufo and convenience of that Animal which they inwrap 5 and very
much
Micrograph i a.
much alfo for the ornament and beauty of it, as will be moft evident to any one that (hall attentively confider the various kinds of cloathings wherewith moft creatures are by Nature inverted and cover’d. Thus I have obferved, that the hair or furr of thole Northern white Bears that inhabite the colder Regions, is exeeeding thick and warm : the like have I obferv’d of the hair of a Greenland Deer, which being brought alive to London^! had the opportunity of viewing 5 its hair was fo exceeding thick, long and foft, that I could hardly with my hand, gralp or take hold of his ikin, and it feem’d fo exceeding warm, as I had never met with any before. And as for the ornamentative ufe of them, it is mort evident in a multitude of creatures,not onely for colour, as the Leopards, Cats,Rhein Deer, d^c. but for the rtiape, as in Horles manes, Cats beards, and leveral other of the greater fort of terrertrial Animals, but is much more conlpi- cuous, in the Vertments ofFiflies, Birds, Inleds, of which I (hall by and by give fome Inrtances.
As for the fkin, the Microfeope difeovers as great a difference between the texture of thofc foveral kinds of Animals, as it does between their hairs , but all that I have yet taken notice of, when tann’d or drefs’d, are of a Spongic nature, and foem to be conrtituted of an infinite company of (mail long fibres or hairs, which look not unlike a heap of Tow or Okum 5 every of which fibres foem to have been fome part of a Mufole, and probably, whil’ft the Animal was alive, might have its dirtind fundi- on, and ferve for the contradion and relaxation of the fkin, and for the ftretching and fhrinking of it this or that way.
And indeed, without foch a kind of texture as this, which is very like that of Spunk^^ it would foem very rtrange, how any body fo rtrong as the fkin ofan Animal uliially is, and lb clofc as it foems, whil’rt the Animal is living, fhould be able to foiffer fo great an extenfion any ways, without at all hurting or dilacerating any part of it. But,fince we are inform’d by the MicrofcopCy that it confirts of a great many finall filaments, which are im- plicated, or intangled one within another, almoft no otherwife then the hairs in a lock of Wool, or the flakes in a heap of Tow, though not alto- gether fo loofe 5 but the filaments are here and there twirted,as twere,or interwoven, and here and there they join and unite with one another,fo as indeed the whole fkin foems to be but one piece,we need not much won- der; And though thefe fibres appear not through aMicrofiope^exuCtly joint- ed and contex’d,as in Sponge 3 yet,as I formerly hinted, I am apt to think, that could we find fome way of difeovering the texture of it, whil’rt it in- verts the living Animal,or had fome very eafie way of foparating the pulp or intercurrent juices, fuchas in all probability fill thofe Interjiitia^wkh- out dilaeerating, brufing, or otherwife fpoiling the texture of it fas it foems to be very much by the ways of tanning and dreffing now us’d) we might difoover a much more curious texture then I have hitherto been able to find 5 perhaps,fomewhat like that of Sponges.
That of Chamoife Leather is indeed very much like that of Spunk^^ lave onely that the foem nothing neer fo even and round, nor alto-
gether fo fmall, nor has it fo curious joints as ^/«»^has, fome of which I
have
Ml C R O G R A P H t A. l6l
have lately difcover’d like thofe of a Sponge, and perhaps all thefe three, bodies may be of the fame kind offiibftance, though two.ofthem indeed- are commonly accounted Vegetable (which, whether they be fb ofi no, I (hall not now difpute) But this feems common to all three, that they undergo a tanning ordreffing, whereby the interfpers’d juices are wafted and wafli’d away before the texture of them can be difcover d.
What their way is of drefling, or curing Sponges, Iconfefs, I cannot learns but the way of drelfing is, by boiling it a good while in a
ftrong Lixivium^ and then beating it very well 5 and the manner of dreft fing Leather is fuflSciently known. _
It were indeed extremely defirable, if fuch a way could be found whereby the Parenchyma, or %fh of the If veral other
parts of the bod,|ymight 'be Wafh’d, or wafted de'an kwa^^, without vitia- ting the form of ihQ fibrous parts or veflells of it, for hereby the texture of thole parts, by the help of a good Microfcope^ might be moft accu- rately found. .
But to digrels no further, we may, flom this diicovery of the Micro- fiope, plainly enough underftand how the Ikin, though it looks lb dole as it docs, comes to give a pafiage to lb vaft a qiiantity of excrementitious fubftances;, as the diligent SatMorius has excellently oblerved it to do, in his medicina fiatica 5 for it feems very probable^.from the texture after diefiing,that there are an infinit of pores that every way pierce it,and that thofe pores are onely filLd with Ibme kind of juice, or fome very pulpy foft fubftance, and thereby the fteams may almoft as ealily find, a paflage through luch a fluid vehicle as the vaporous bubbles which ^e generated at the bottom of a Kettle of hot water do find a paflage through that fluid medium into the ambient Air. '
Nor is the fkin of animals only thus pervious,but even thofe of vegetables alfo feem to be the lame^for otherwife I cannot conceive why,iftwo fprigs of Rofemary (for Inftance) be taken as cxaftly alike in all particulars as can be, and the one be fet with the bottom in a Glals of water, and the other be let juft without the Glals, but in the Air onely, though you ftop the lower end of that in the Air very carefully with Wax, yet lhallit prefently almoft wither, whereas the other that feems to have a fupply from the liibjacent water by its fmall pipes, ox microfcopical lerves its greennels for many days, and Ibmetimes weeks.
Now, this to me, feems not likely to proceed from any other caufe then iho avolation of the juice through the Ikin, for by the Wax,all thofe other pores^of the ftem are very firmly and clofely ftop’d up. And from the more oriels poroufnelsof the fkins or rinds of Vegetables may, perhaps, be ' Ibmewhat of the realbn given, why they keep longer green, or fooner wi^
I ther 5 for we may obferve by the bladdering and craking of the leaves of Bays, Holly, Laurel, &c, that their Ikins are very clofe, and do not fuffer 1 fo free a paflage through them of the included juices. '
, But of this, and of the Experiment of the Rofemary, I lhall elfewhere 1 more fully confider,it feeming to me an extreme Juciferous Experiment,
1 luch as feems indeed very plainly to prove the Schematifm or ftru^ure
Z of
i62
Micrographia.
of Vegetables zltogGther mechanical, and as necefiary, that (water and warmth being apply’d to the bottom of the fprig of a Plant) feme of it (hould be carried upwards into the ftem, and thence diftributed into the leaves, as that the water of the covering the bottom of the Mills
at the Bridge foot of London, and by the ebbing and flowing of it, paf- fling ftrongly by them, fhould have fbme part of it convey'd to the Cefterns above,and thence into feveral houfes and Cefterns up and down the City.
Obferv. XXXIII. Of the Scales of a Soal, and other Fijhes,
HAving hinted fbmewhat of the ikin and covering of terreftrial Ani- mals, I (hall next add an Obfervation I made on the fkin and Scales of a Soal, a fmall Fifh, commonly enough known 5 and here in Fifties, as well as other Animals, Nature follows its ufual method, framing all parts fo, as that they are both ufefull and ornamental in all its compofures, mingling utile and dulce together , and both thele defigns it feeras to follow,though our unaflifted fenfes are not able to peceive them ; This is not onely manifeft: in the covering of this Fifh only, but in multitudes of others, which it would be too long to enumerate, witnefs particularly that final! Sand Shell, which I mention'd in the X I. Obfervation, and infinite other fmall Shells and Scales, divers of which I have view'd. This fkin I view’d, was fiead from a prettylargc Soal, and then expanded and dry’d, the infide of it, when dry, to the naked eye, look'd very like a piece of Canvafs,but the Micro fc^e difeover’d that texture to be nothing elfe,but the inner ends of thofc curious Scolop'd Scales I, I, I, in the fecond FjgHre of the XXL Scheme, namely, the part of G G G G (of the larger repre- fentation of a Angle Scale, in the firff Figure of the fame Scheme) which on the back fide, through an ordinary fingle Magnifying Glafs, look'd not unlike the Tyles on an houfe.
The outfide of it, to the naked eye, exhibited nothing more of orna- ment, favethe ufual order of ranging" the Scales into a triagonal ioxm, onely the edges feem'd a little to fhine, the finger being mbb d from the tail-wards towards the head, the Scales feem’d to ffay and raze it ^ Bat through an ordinary Magnifying glafs, it exhibited a moft curioufly carved and adorned furface, fuch as is vifible in the fecond Figure, each of thofe (formerly almoft imperceptible) Scales appearing much of the fliape I, I, I, that is, they were round, and protuberant, and fomewhat fbap’d like a Scolop, the whole Scale being creas d with curioufly wav'd and indented ridgcs,with proportionable furrows between^each of which was terminated with a very fharp tranfparent bony fubfrance,which,like fb many fmall Turnpikes, feem'd to arm the edges.
The back part K K K was the fkin into which each of thefe Scales were very deeply fix*d, in the curious regular order, vifible in the fecond
Figure.
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M I C R O G R A P H i A.
Figure. The length andfhapeoF the part of the Scale which was buried by the fkin^is evidenced by the firft Figure-^ which is the reprefentation of one of them pluck'd out and view'd^ through a good Microfcope^ namely^ the part' L F G G F L, wherein is alfo more plainly to be feen^the manner of carving of the fcclopt part of every particular Scale^how each ridge or barr FEE is alternately hollowed or engraven, and how every gutter between them is terminated with very tranrparent and hard pointed fpikes, and how every other of thele, as A A A A, are much longer then the interjacent ones, D D D.
The texture or form alfo of the hidden part appears, namely, the middle part, G G G, Teems to conhft of a great number of fmall quills or pipes, by which, perhaps, the whole may be nourifhed , and the lide parts F F confift of a more fibrous texture, though indeed the whole Scale leem'd to be of a very tough grilly fubfi:ance,like the larger Scales of other Fifhes.
The Scales of the fkin of a Dog-fifh (which is us'd by fuchas workin Wood,for the fmoothing of their work, and confifts plainly enough to the naked eye. of a great number of fmall horny points) through the Alter ofcope appear’d each of them curioully ridg’d, and very neatly carved 5 and in- deed, you can hardly look on the fcales of any Fifh, but you may diicover abundance of curiofity and beautifying^ and not only in thefe Fifhes, but in the (hells and crufts or armour of mold (brts of Marine Animals (b inveftedi
Obicrv. XXXIV. Of the Sting cf a Bee*
THe Sting of a Bee^ delineated in the fecond Figure of the ysMl.Scheme^ (eems to be a weapon of offence, and is as great an Inftance, that Nature did realy intend revenge as any, and that firft, becaufc there feems to be no other ufe of it. Secondly, by reafon of its admirable fltape, Teeming to be purpofely fhap’d for that very end. Thirdly,from the vi- rulency of the liquor it ejects, and the fad effects and fymptoms that fol- low it.
But whatever be the ufe of it,certain it is,that the flrudture of it is very admirable 5 what it appears to the naked eye, I need not deferibe, the thing being known almoft to every one,but it appears through the Micro- jeope^ to confift of two parts, the one a fheath, without a chape or top, fhap’d almoft like the Holfter of a Piftol, beginning at d, and ending at this fheath I could moft plainly perceive to be hollow, and to con- tain in it, both a Sword or Dart, and the poifonous liquor that caufes the pain. The fheath or cafe feem d to have feveral joints or lettings together, marked hyfg hih^lmno^ it was arm’d moreover neer the top, with fe- veral crooks or forks (^pqrf t') on one fide, and (^p q r ft u') on the other, each of which Teem’d like fo many Thorns growing on a briar, or rather like To many Cat’s Claws 3 for the crooks themfelves Teem’d to be little lharp tranfparent points or claws, growing out of Ym\e protuberancies on
Z 2 the
Ml
CROGRAHP I A.
the fide of the (heath, which, by obferving the Figure diligently, is e$fic enough to be perceiv’d ^ and from feveral particulars, I fuppofe the Ani- mal has a power of difplaying them, and (hutting them in again as it pleaies, as a Cat does its claws, or as an Adder or Viper can its teeth or fangs.
The other part of the Sting was the Sword, as 1 may fo call it, which is (heath’d, as it were,in it, the top of which a b appears quite through at the (mailer end, juft as if the chape of the (heath of a Sword were loff, and the end of it appear’d beyond the Scabbard ; the end of this Dart(' was very (harp, and it was arm’d likewife with the like Tenterhooks or claws with thofe of the (heath, (iich as { v xy^ xy % z.) thefe crooks, I am very apt to think, can be clos’d up alfo, or laid fiat to the (ides of the Sword when it is drawn into the Scabbard,as I have (everal times obferv’d it to be, and can be (pred again or extended when ever the Animal pleales.
The confideration ofwhich'very pretty ftrufture,has hinted to me,that certainly the uleof thefe claws (eems to be very confiderable, as to the main end of this Inftriiment, for the drawing in, and holding the ding in the flefh , for the point being very (harp, the top of the Sting or Dagger (4 h') is very eafily thruft into an Animal’s body,which being once entred, the Bee, by endeavouring to pull it into the fheath, draws (by reafbn of the crooks ( v xy ) and (^xyzz,') which lay hold of the (kin on either fide) the top of the (heath (^tfrv') into the (kin after it, and the crooks and r, z;, being entred, when the Bee endeavours to thruft out the top of the ding out of the (heath again, they lay hold of the (kin on ei- ther fide, and fo not onely keep the fheath from (lifting back, but helps the top inwards, and thus, by an alternate and fuccefhve retracing and emitting of the Sting in and out of the (heath, the little enraged creature by degrees makes his rcvengfull weapon pierce the tougheft and thickeft: Hides of his enemies, in fo much that (bme few of thefe ftout and re(b- lute (bldiers with the(e little engines, do often put to flight a huge mafty Bear, one of their deadly enemies, and thereby (hew the world how much more confiderable in Warr a few (kilfull Engineers and refblute (bldiers politickly order’d, that know how to manage (uch engines, are, then a vaft unweildy rude force, that confides in, and ads onely by, its ftrength. But (to proceed) that he thus gets in his Sting into the fkin, I conjedure, becaufe, when I have obferv’d this creature living, I have found it to move the Sting thus, to and fro, and thereby alfo, perhaps, does, as ’twere, pump or force out the poilbnous liquor, and make it hang at the end of the (heath about in a d rop. The crooks, I fuppo(e al(b to be the caufe why thefe angry creatures, haftily removing them- (elves from their revenge, do often leave the(b weapons behind them, ftieath’d, as ’twere, in the flefh, and, by that means, caufe the painfull lymptoms to be greater,and more lafting, which are very probably caus’d, partly by the piercing and tearing of the fkin by the Sting, but chiefly by the corrofive and poifonous liquor that is by this Syringe-pipe con- vey’d among the fenfitive parts thereof and thereby more eafily gnaws
and
Micrograph! A;
and corrodes thofe tender fibres : As I have (hewed in the dclcription of a Nettle and of Cowhagc.
Obferv. XXXV. Of the contexture and Jhapecf thepartkks of Feathers.
Examining feveral forts of Feathers^ I took notice of the(e particulars in all forts of wing-Feathers, efpecially in thofc which ferv’d for the beating of the air in the aftion of dying.
That the outvvard (urface of the Quill and Stem was of a very hard,(fif?5 and horny fubftance, which is obvious enough, and that the part above tlie Quill was fill d with a very white and light pith, and, with the Micro- fcope^ I found this pith to be nothing ehe, but a kind of natural congeries of fmall bubbles, the films of which (eem to be of the fame fubftance with that of the Quill, that is, of a ftiff tranfparent horny fubftance.
Which particular feems to rae,very worthy a more ferious confiderationj For here we may obferve Nature,as ’tvvere,put to its (hifts, to make a fub- fiance,which (hall be both light enough,and very ftiffand ftrong,without varying from its own eftabli(h'd principles, w^hich we may obferve to be (hch, that very ftrong bodies are for the moft part very heavic al(b, a (rrength of the parts ufually requiring a denfity, and a denfity a gravity 5 and therefore fhould Nature have made a body (b broad and fo ftrong as a Feather, almoft, any other way then what it has taken, the gravity of it muft neceflarily have many times exceeded this 5 for this pith (eems to be like fo many ftops or crofi pieces in a long optical tube, which do very much contribute to the ftrength of the whole, the pores of which were fuch, as that they (eem’d not to have any communication with one ano- ther, as I have elfewhere hinted.
But the Mechanifm of Nature is ulually fo excellent, that one and the fame (ubftance is adapted toferve for many ends. For the chief ufe of this, indeed, feems to be for the lupply of nouri(hment to the downy or . feathery part of the ftem 5 for ’tis obvious enough in all forts of Feathers, that ’tis plac'd juft under the roots of the branches that grow out of ei- ther fide of the quill or ftalk, and is exaftly fhap’d according to the rank- ing of thole branches, coming no lower into the quill, then juft the be- ginning of the downy branches, and growing onely on the under fide of of the quill where thole branches do (b. Now, in a ripe Feather (as one may call it'^ it feems difficult to conceive how the Snccus nutritius fhould be convey'd to this pith 5 for it cannot, I think, be well imagin’d to pa(s through the (ubftance of the quill, fince, having examin'd it with the greateft diligence I was able, I could not find the lead: appearance of pores 5 but he that fhall well examine an unripe or pinn'd Feather, will plainly enough perceive the Veflel for the conveyance of it to be the thin filmy pith (as tis call’d) which pafles through the middle of the quill.
As for the make and contexture of the Down it (elf, it is indeed very
rare
Micrographia.
rare and admirable, and fuch as I can hardly believe,that the like is to be dilcover d in any other body in the world 5 for there is hardly a large Feather in the wing of a Bird. but contains neer a million of diftindb parts, and every one of them fhap'd in a mod: regular & admirable form,adapt- edto a particular Defign : For examining a middle ciz’d Gooie-quill, I eafily enough found with my naked eye,that the main ftem of it contain’d about 300. longer and more Downy branchings upon one fide, and as many on the other of more ftiff but fomcwhat (hotter branchings. Many of thele long and downy branchings, examining with an ordinary Mi- crojcope^ I found divers of them to contain neer 1200, fmall -leaves (as I may call them, (itch as E F of the fii ft Figure of the 23. Scheme) and as many (talks 5 on the other fide, (uch as I K of the lame Figure, each of the leaves or branchings, E F, (eem’d to be divided into about fixteen or eighteen fmall joints, as may be feen plainly enough in the Figure, out of molt of which there (eem to grow fmall long fibres^ fuch as are exprels’d in the Figure, each of them very proportionably (hap’d according to its pofition, or plac’d on the (talk E F ^ thofe on the under fide of it, name- ly, 1, 2, 3, 4, 5, 6, 7, 8, 9, &c. being much longer then thole directly op- ' polite to them on the upper 5 and divers of them, fuch as 2,3,4,5,6,7,839, <d^c. were terminated with fmall crooks, much relembling thole foall crooks,which are vifible enough to the naked eye, in the leed-buttonsof Bur-docks. The (talks likewife, I K on the other fide, feem’d divided into neer as many fmall knotted joints,but without any appearance of ftrings or crooks,each of them about the middle K,lcem’d divided into two parts by a kind of fork, one fide of which, namely, K L, was extended neer the length of K I, the other, M, was very Ihort.
The tranlverfe Sections of the Items of thefe branchings, manifefted the (hape or figure of it to be much like I N O E, which confilted of a horny fkin or covering, and a white feemingly frothy pith, much like the make of the main Item of a Feather.
The ule of this Itrange kind of form,is indeed more admirable then all the reft, and fuch as delerves to be much more ferioully examin’d and confider’d, then I have hitherto found time or ability to do 5 for certain- ly, it may very much inftruft us in the nature of the Air, elpecially as to fome properties of it.
The Items of the Downy branches IN O E, being rang’d in the order vifible enough to the naked eye, at the diftancc of! F, or fomcwhat more, the collateral (talks and leaves (if I may lb call thole bodies I new- ly defcribed) are fo rang’d, that the leaves or hairy (talks of the one fide lie at top, or are incumbent on the (talks of the other, and crols each> other, much after the manner exprefs’d in the lecond Figure of the '2^. Scheme^ by which means every of thole little hooked fibres of the leaved (talk get between the naked (talks, and the (talks being full of knots, and a prety way dif-join’4, fo as that the fibres can eafily get be- tween them, the two parts are fo clolely and admirably woven together, that it is able to impede,for the greateft pa^t, the tranfeurfion of the Air 5 and though they are fo exceeding, fmall, as that the thicknels of one of
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MicrograpHiaj
thefc ftalks amounts not to a 500. part of ah Inch, yet do they compole fo fb'ong a texture, af,notwithftanding the exceeding quick and violent beatiug of themagainft the Air, by the ftrength of the Birdswing, they firmly hold together. And it argues an admirable providence of Nature in the contrivance and fabrick of tlieni^ for their texture is fuch, that thousji by any external in)tu*y the parts of them are violently dif joyn’d, fo as "that the leaves and ftalks touch not one another, and confequently feveralof thefe rents would impede the Bird’s flying, yet, for the moft part, of themfelves they readily re-join and re-contex themfclves,and are eafit}' by the Birds ftroking tlie Feather, or drawing it through its Bill, all of them fettled and woven into their former and natural pofture 5 for there are fuch an infinite company of fibres in the under fide
of the leaves, and moft of them have fuch little crooks at their ends,thac they readily catch and held the ftalksthey touch.
From which ftrange contexture,it ftems rational to fuppolc that there is a certain kind of mefh or hole fo fmall, that the Air will not very eafily pals through it, as I hinted allb in the fixth Obfervation about ImallGlais Canes, for otherwife it feems probable, that Nature would have drawn over lomc kind of thin film which Ihould have covered all thofe almoft fquare m.efhes or holes, there feeming through the Microfeope to be more then half of the liirface of the Feather which is open and vifibly pervi- ous ^ which conjefrure will yet feem more probable from the texture of the brufhie wings of the 7mea argentea^ or white Feather wing’d moth, which I Ihall anone delcribe. But Nature, that knows beft its own laws, and the leveral properties of bodies,knovvs alfo beft how to adapt and fit them to her defigned ends,and whofo would know thofe properties, muft endcavoitr to trace Nature in its working, and to fee what courfe fhe obferves. And this I fuppofe will be no inconfiderable advantage which the Schematifms and Strudures of Animate bodies will afford the dili- gent enquirer, namely, moft lure and excellent inftrudions, both as to the pradical part of Mechanic ks and to the iheory and knowledge of the nature of the bodies and motions.
Obferv. XXXVI. Of Pcacoks, Ducks., and other Feathers (f changeable colours.
'^He parts of the Feathers of this glorious Bird appeal*, through the Microfeope^ no lels gaudy then do the whole Feathers, for, as to the naked eye ’tis evident that the ftem or quill of each Feather in the tail lends out multitudes of Lateral branches, fuch as A B in the third Figure of the 25. Scheme reprelents a fmall part of about p part of an Inch long, and each of the lateral branches emit multitudes of little Iprigs, threads or hairs on either fide of them, fuch as C D, C D, C D, fo each of thofe threads in the appears a large long body,conlifting of amultb
rude
rCROGRAPHi A.
tude of bright rcfiefting parts, whole Figure ’tis no eafie matter to de- termine, as he that examines it fhall find, tor every new pofition of it to the light makes it perfectly feem ofanother form and fhape,and nothing what it appear’d a little before^ nay, it appear’d very differing oft- times from ib feemingly inconfiderable a circumftance, that the inter- pofing of ones hand between the light and it, makes a very great change, and the opening or (hutting a Cafement and the like, very much diverfi- fies the appearance. And though, by examining the form of it very many ways, which would be tedious here to enumerate, I fuppofe I have diF cover’d the true Figure of it, yet oftentimes, upon looking on it in ano- ther pofture, I have almoft thought my former obfervations deficient, though indeed, upon further examination, I have found even thoieaUb to confirm them.
Thefe threads therefore I find to be a congeries of fmall Lamins or plates, as e c e e e, &c. each of them (hap’d much like this a h c </, in the fourth Figure^thc part a c being a ridge, prominency, orftem, and b and d the corners of two (mall thin Plates that grow unto the (mall ftalk in the middle, fo that they make a kind of little feather, eachoftheic Plates lie one dole to another,almofl: like a company of (loping ridge or cutter Tyles^ they grow on each fide of the ftalk oppofite to one another, by two and two, from top to bottom, in the manner cxprels’d in the fifth Figure, the tops of the lower covering the roots of the next above them 5 the under fide of each of thefe laminated bodies, is ofa very dark and opacous fubftance, and (uffers very few Rays to be trajefted, but rc- fiefts them all toward *that fide from whence they come, much like the foil of a Looking-gla(s 5 but their upper (ides (eem to me to confift of a multitude of thin plated bodies, which arc exceeding thin, and lie ve- ry clofe together, and thereby, like mother of Pearl (hells, do not one- ly refleft a very bri(k light, but tinge that light in a moft curious man- ner 5 and by means of various pofitions, in relpeft of the light, they re-* fleft back now one colour, and then another, and thofe moft vi- vidly.
Now, that the(e colours are onely fantajlical ones, that is, fuch as ari(c immediately from the refradionsof the light, I found by this, that water wetting thefe colour’d parts,deftroy’d their colours, which feem'd to pro- ceed from the alteration of the refiedion and refradion. Now, though I was notable to (ee thole hairs at all tranlparent by a common light, yet by looking on them againft the Sun, I found them to be ting’d with a darkilh red colour, nothing a-kin to the curious and lovely greensand blues they exhibited.
What the reafon of colour feems to be in fuch thin plated bodies, I have elfewhere (hewn. But how water caft upon thole threads deftroys their colours, I fuppole to be perform’d thus 5 The water falling upon thefe plated bodies from its having a greater congruity to Feathers then the Air,infinuates it felf between thofe Plates,and (b extrudes theftrong refleding Air, whence both thefe parts grow more tran(parent,as the Mi- crofiche informs, and colourlels allb, at beft retaining a very faint and
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Micrographia.
dull colour. But this wet being wafted a v/ay by the continual cvapora- tions and fteams that pafs through them from the Peacock, whil’ft that Bird is yet alive, the colours again appear in their former lufter, the terjiitia oi Plates being fill’d with the ftrongly reflefting Air.
The beauteous and vivid colours of the Feathers of this Bird, being found to proceed from the curious and exceeding fmalneft and fineneis of the reflecting parts, we have here the rcafon given us of all thole gau-^ deries inthe apparel of other Birds allb, and how they come to exceed the colours of all other kinds of Animals, befides InfeCts 5 for fince (as we here,and ellewhere alfo Ihew) the vividnels of a colour, depends upori the fineneis and tranfparency of the reflecting .and refraCting parts, and fince our Microfcepe dilcovers to us, that the component parts of feathers are fuch,and that the hairs of Animals are otherwile^ and fince we find alfo by the Experiment of that Noble and molt Excellent Perlbn I former- ly named ^ that the difference between Silk and Flax, as to its colour, is nothing elfe (for Flax reduc’d to a very great fineneis of parts, both white and colour’d, appears as white and as vivid as any Silk, butloles that brightnels and its Silken alpeCt as foon as it is twiftcd into thread,by realbn that the component parts, though very Imall and fine, are yet pli- able flakes, and not cylinders, and thence,by twilling, become united in- to one opacous body, whereas the threads of Silk and Feathers retain their luftre, by preferving their cylindrical form intire without mix- ing ; fo that each refleCfed and refraCled beam that compofes the glols of Silk, preferves its own property of modulating the light intire) 5 And fince we find the fame confirm’d by many other Experiments elfewhcre mentioned, I think we may fafely conclude this for an Axiome, that wherefoever we meet with tranfparent bodies, Ipun out into very fine parts, either deer, or any ways ting’d, the colours refulting from fuch at compo^tion muft neceftarily be very glorious, vivid, and deer, like thole of Silk and Feathers. This may perhaps hint lome ufefull way of making other bodies, befides Silk, be fulceptible of bright tinCtures, but of this onely by the by.
The changeable colour’d Feathers alfo of Ducks, and leveral other Birds, I have found by examination with my Microfeope, to proceed from much the fame caules and textures*
Obferv. XXXVII, Of feeit of Flies, and fever al other \n^ fedls.
THe foot of a Fly (delineated in thefirft Figure of the 2:^. Scheme, which reprefents three joints, the two Tallons, and the two Pattens in a flat pofture j andin the fecond Figure of the lame Scheme, which re- prefents onely one joint, the Tallons and Pattens in another pofture) is of a moft admirable and curious contrivance, for by this the Flies are in- abled to walk againft the fides of Glals, perpendicularly upwards, and to
A a contain
MiCROGR AP H I A. (
contain themfelves in that pofture as long as they pleafe^nayjto wathan’d fufpend themfelves againft the under furface ofmany bodies,as the ceiling of a room, or the like, and this with as great a Teeming facility and firm^ nels, as if they were a kind oi Antipodes^ and had a teudettcy upwards, as we are fure they have the contrary, which they alfo evidently difcOver, in that they cannot make themfelves fo light, as to flick or fufpend themi felves on the under furface of a Glafs well polilh’d and cleans’d 5"^ their fufpenfi on therefore is wholly to be afcrib’d to fome Mechanical contrr- vance in their feet , which, what it is, we (hall in brief explain, by fhewi- ing, that its Mechanifm confifts principally in two parts, that is, firft its two Claws, or Tallons, and fecondly, two Palms, Pattens, or Soles. .
The two Tallons are very large, in proportion to the foot, and hand- fomly Ihap’d in the manner defcrib’d in the Figures^ by A B, and A C, the bigger part of -them from A to is all hairy, or briOed, but to- ward the top, at C and B fmooth, the tops or points, which feem very (harp turning downwards and inwards, are each of them mov’d on a joint \ at A, by which the Fly is able to open or fhut them at pleafure, fo that ; the points B and C being entered in any pores, and the Fly endeavouring tofhut them,theClaws not onely draw one againft another, and fo faften each other, but they draw the whole foot, G G A D D forward, fo that on a foft footing, the tenters or points G G G G, (whereof a Fly has about ten in each foot, to wit,two in every joint) run into the pores,if they find any, or at leaft make their way 5 and this is fenfible to the naked eye, in the feet of a Chafer^ which, if he be fufter’d to creep over the hand, or any other part of the fkin of ones body, does make his fteps as fenfible to the touch as the fight.
But this Contrivance, as it often fails the Chafer^ when he walks on hard and clofe bodies, fo would it alfo our Fly, though he be a much lefler, and nimbler creature, and therefore Nature has furnifti’d his foot with another additament much more curious and admirable, and that is, with a couple of Palms, Pattens or Soles D D, the ftrudture of which is this:
From the bottom or under part of the laft joint of his foot, K, arifo two fmall thin plated horny fubftances, each confifting of two flat pieces, D D, which feem to be flexible, like the covers of a Book, about F F, by which means,the plains of the two fides E E,!do not always lie in the fame plain, but may be fometimes (hut clofer, and fo each of them may take a little hold themfelves on abody^ but that is not all,for the under fides of thefe Soles are all befet with (mail brifles, or tenters, like the Wire teeth of a Card ufed for working Wool, the points of all' which tend for- wards, hence the two Tallons drawing the feet forwards, as I before hinted, and thefe being applied to the furface of the body with all the
Eoints looking the contrary way, that is, forwards and outwards, if there eany irregularity or yielding in the forface of the body, the Fly fu- fpends it felfvery firmly and eafily, without the accels or need of any fuch Sponges fill’d with an imaginary as many have, for want of good
Glafles, perhaps, or a troublefome and diligent examination, fuppos’d. Now, that the Fly is able to walk on Glaft, proceeds partly from fome
ruggedneft
M I C R OG R A PH 1 A.
ruggednefs of the lurface ; and chiefly from a kind of tarnilh, or dirty (moaky fubftance, which adheres to the furface of that very hard body 5 and though the pointed parts cannot penetrate the fubftanCe ofCIafs^yet may they find pores enough in the tarnifhj or at leaftmake them.
This &ru^ure I fomewhat the more diligently furvey’d, Tjecaufe I could not well comprehend, how, if there were fuch a glutinous matter in thofe fuppofed Sponges, as moft (that have , oblerv’d that Objefi: in a Mzerojeope) have hitherto believ’d,how, I fay, the Fly could fb readily un*- glew and loofen its feet ; and, becaufe I have not found any other crea- ture to have a contrivance any Ways like it 5 and chiefly, that we might not be caft upon unintelligible explications of the Ph^nontefta of Nature, at leaft others then the true ones, where our fenfes were able to furnifh us with an intelligible, rationall and true one.
Somewhat a like contrivance to this of Flies (hall we find in moft other Animals, fuch as all kinds of Flies and cafe-wing'd creatures 5 nay, in k Flea, an Animal abundantly fmaller then this Fly. Other creatures, as Mites, the Land-Crab, have onely one ftnall very fharp Tallon at the end of each of their legs, which all drawing towards the center or middle of their body, inable thefe exceeding light bodies to fiif^nd and faften themlelvcs to almoft any lurface.
Which how they are able to do, will not feem ftrange, if we confider, firft, how little body there is in one of thefe creatures compar’d to their fuperficies, or outfide, their thicknefs, perhaps, oftentimes,not amounting to the hundredth part of an Inch : Next, the ftrength and agility of thefe creatures compar’d to their bulk, being, proportionable to their bulk, perhaps, an hundred times ftronger then an Horfe or Man. And thirdly, if we confider that Nature does always appropriate the inftruments, fb as they arc the moft fit and convenient to perform their offices, and the moft fimple and plain that poffibly can be 5 this we may fee further veri- fy’dalfointhefootof aLoufe which is very much differing firom thofe I have been defcribing, but more convenient and neceflary for the place of its habitation, each of his leggs bdng footed with a couple of final! claws which he can open or fhut at pleafure, fhap’d almoft like the claws of a Lobfter or Grab,but with appropriated contrivances for his peculiar life, which being to move its body 'to and fro upon the hairs of the crea- ture it inhabits, Nature hasfurnilh’d one of its claws with joints, almoft like the joints of a man s fingers, fb as thereby it is able to encompafs or gralp a hair as firmly as a man can a ftick or rope.
Nor, is there a Ids admirable and wonderfull Mechamjm in the foot of a Spider, whereby he is able to fpin, weave, and climb, or run on his curious ftranlparent clew, of whichlfhalllaymorein the defeription of that Animal.
And to conclude, we fhall in all things find, that Nature does not onely work Mechanically, but by fuch excellent and moft compendi- ous, as well as ftupendious contrivances, that it Were impoffible for all the realbn in the world to find out any contrivance to do the fame thing that fhould have more convenient properties. And can any be fb fottifh,
A a 2 as
171
Micrographia.
as to think all thofe things the productions of chance > Certainly, ei» ther their Ratiocination muft be extremely depraved,or they did never attentively confider and contemplate the Works of the Al-mighty.
Oblerv. XXXVIII. Of the StruSluTe and motion oftheWing& ^Flics.
He Wings of all kinds oflnfeCts, are, for the moft part , very ■*- beautifull ObjeCts, and afford no lefs pleafing an Ob jeCt to the mind toipeculate upon,then to the eye to behold. This oftheblueFly,among the reft, wants not its peculiar ornaments and contrivances , it grows out of the ihorax^ or middle part of the body of a Fly, and is feated a little beyond the center of gravity in the body towards the head, but that Excentricly\sc\xvio\xi\y balanc’d ^firft, by the expanded ofthc wings which lies all more backwards then the root, by the motion of them,whcreby the center of their vibration is much more backwards to- wards the tail of the Fly then the root of the wing is. What the vibra- tive motion of the wings is, and after what manner they are moved, I have endeavoured by many trials to find out : And for the firft manner of their motion, I endeavoured to obferve feveral of thole kindoflmall Ipinning Flies, which will naturally fulpend themfelves, as it werje, pois’d and fteady in one place of the air, without riling or falling, or moving forwards or backwards , for by looking down on thofe, I could by a kind of faint lhadow, perceive the utmoft extremes of the vibrative moti- on of their wings, which lhadow, whil’ll: they lb endeavoured to lulpend themfelves, was not very long, but when they endeavour’d to flie for- wards,it was fomewhat longer 5 next,I tried jt,by fixing the leggs of a Fly upon the top of the ftalkof a feather, with Clew, Wax, and then making it endeavour to flie away ^ for being thereby able to view it in any pofture, I colleded that the motion of the wing was after this man- ner. 1 he extreme limits of the vibrations were ufually Ibmewhat about the length of the body diftant from one another, oftentimes lhortcr,and Ibmetimes allb longer 5 that the formoft limit was uliially a little above the back, and the hinder fomwhat beneath the belly ^between which two limits, if one may ghels by the found, the wing Teem’d to be mov’d for- wards and backwards with an equal velocity : And if one may (from the fhadow or faint reprefentation the wings afforded, and from theconfide- ration of the nature of the thing ) ghels at the pofture or manner of the wings moving betweeen them, it Teem’d to be this; TheTwing being Tuppos’d placed in the upmoft limit. Teems to be put lb that, the plain of it lies almoft horizontal^ but onely the forepart does dip a little^ or is Ibmewhat more depreft 5 in this pofition is the wing vibrated or mov’d to the lower limit , being almoft arrived at the lower li- mit , the hinder part of the wing moving fomewhat fafter then the
former.
M I C R O G R A P H l4.
fbrmerj the Aren of the wing begins to dipbehindj a'nd in that pdfture feems it to be mov’d to the upper limit back again, and thence back again in the firft pofturCjthe former part of the Area dipping again,as it is moved downwards by means of tfie quicker motion of the main ftera which terminates or edges the forepart of the wing. ' And thefe vibrati- ons or motions to and fro between the two limits feehi lb Iwift, that ’tis very probable (from the found itafiords, if it be compar’d with the vi- bration of a mufical firing, tun’d unilbn to it) it makes many hundreds, if not Ibme thoulands of vibrations in a fecond minute of time. And, if we may be allow’d to ghels by the found, the wing of a Bee is yet more’ fwift, forthe tone is much more acute, and that, in all likelihood, pro- ceeds from the exceeding fwift beating of the air. by the Imall wing. And it feems the more likely too, becaufe the wing of a. Bee is lefsin pro- portion to its body, then the other wing to the body of a Fly ^ fo that for ought I know, it may be one of the quickefc vibrating JpontaKeous moti- ons of any in the world 5 and though perhaps there may be many Flies in other places that afford a yet more fhrill noife with their wings, yet ’tis molt probable that the quickeft vihratmgjpofttaneou^ motion is to be found in the wing of Ibme creature. Now, if we confider the exceeding, quicknefs of thefe Animal fpirits that muff caufe thefb: motions, we cannot chufe but admire the exceeding vividnels of the governing faculty or Anima of the Infe^, whicsh is able to dilpofe and regulate fb the the mo- tive faculties, as to caufe every peculiar organ, not ondy to move or adt fo quick, but to do it alfb fb regularly.
Whil’ft I was examining and confidering the cniiom Mechanifm of the wings,! obferv’d that under the wings of mofi: kind of Flies, Bees, there were plac’d ctrtain pendulums or extended drops (as I may fo call them from their refembling motion and figure) for they much refembled a long hanging drop of fbme tranfparent vifcous liquor 5 and I obferved them conftantly to move juft before the wings of the Fly began to move, fb that at the firft fight I could not but ghefs, that there was fome excel- lent ufe^ as to the regulation of the motion of the wing, and did phancy, that it might be fbmething like the handle of a Cock, wBich by vibra- ting to and fro,might,as ’twcre.open and fhut the Cock,and thereby give a paflage to the determinate influences into the Mufcles 5 afterwards, up- on fbme other trials,! fuppos’d that they might be for fome ufe in refpira- tion, which for many reafons ! fuppofe thofe Animals to ufe, and, me thought, it was not very improbable, but that they might have! conve- nient paflages under the wings for the emitting, at leaft,of the air, if not admitting, as in the gills of Fifties is moft evident 5 or, perhaps, this rc«- dulum might be fomewhat like the ftaff to a Pump, whereby thefe crea- tures might exercife their Analogus lungs, and not only draw in, but force outjthe air they'live by ; but thefe were but conjefturcs,and upon further examination feem’d lefs probable.
The fabrick of the wing,as it appears through a moderately magnify- ing M/croJcepe Jhems to be a body confifting of two parts.as is vifible in the ^.Figure of the '2^.Scheme!)and by the '2, Figure of the 26. Scheme'-^ the one is
a quilly
ICROGRAHPIA.
a quilly or finny lubfianccjconfifting of feveral longjflendcr and varioufly bended quills or wires, Ibmething refembling the veins of leaves 5 thele are, as ’twere,the finns or quills which ftifFen the whole Arca^ and keep the other part diftended, which is a very thin tranfparent Ikin or mem- brane varioufly folded, and platted, but not very regularly, and is be- fides exceeding thickly beftuck with innumerable fmall brifles, which are onely perceptible by the bigger magnifying Microfcope^ and not with that neither, but with a very convenient augmentation of Iky- light projected on the Objeft with a burning Glafs, as I have elfewhere (hew a, or by looking through it againfl: the light.
In ftecd of thefe fmall hairs, in feveral other Flies, there are infinite of fmall Feathers, which cover both the under and upper fides of this thin film as in almoft all the forts of Butterflies and Moths: and thole fmall parts are not onely (hap’d very much like the feathers of Birds, but likethofe variegated with all the variety of curious bright and vivid colours ima- ginable 5 and thofe feathers are likewife fo admirably and delicately rang’d,as to compofe very fine flourifhings and ornamental paintings,like Turkic and Perfan Carpets,but of far more forpafling beauty, as is evident enough to the naked ey®, in the painted wings of Butterflies, but much more through an ordinary Microfeope.
Intermingled likewife with thele hairs, may be perceived multitudes oflittle pits, or black lpots,in the cxended membrane, which feemto be the root of the hairs that grow on the other fide 3 thele two bodies feeia dilpers’d over the whole furface of the wing.
The hairs are bell: perceiv’d, by looking through it againfl the light, or, by laying the wing upon a very white piece of Paper, in a conve- nient light , for thereby every little hair mofl manifeflly appears 3 a Specimenloi which you may oblerve drawn in the fourth Figure of the 2^, Scheme^ A»B, CD, EF whereof reprefent fome parts of the bones or quills of the wing, each of which you may perceive to be cover’d] over with a multitude of foales, or brifles , the former A B, is the biggefl flem of all the wing, and may be properly enough call’d the cut-air, it being that which terminates and fliflfens the formofl edge of the wing 3 the fore-edge of this is arm’d with a multitude of little brifles, or Tenter-hooks, in fome flanding regular and in order, in others not 5 all the points of which are direfted from the body to- wards the tip of the wing*, nor is this edge onely thus fring’d , but even all the whole edge of the wing is cover’d with a fmall fringe, confifling of fhort and more flender brifles.
This Subjeft, had I time, would afford excellent matter for the con- templation of the nature of wings and of flying 3 but, becaufe I may, perhaps, get a more convenient time to profecute that (peculation, and recoUedf Icvcral Oblervations that I have made of that particular. I (hall at prelcnt proceed to
Obferv.
Gbferv,. X X X ] X. Of the Ejes cmd Head of a Greydfonc-Fiy,- and of fever al other creatures.
I took a large grey that had a large teadj but a fmall and
(lender body in proportion to iFand cutting off its head, i fix’d; it with the forepart or face upwards upon my Object Piate Xihis I made choice ofrather then the head ofa great blue Fly.beCaufe my enquiry being nov7 about the eyes,! found this P jy to have, fii(t the biggeft cluders of eyes in proportion to his head, of any (mall kind ol Ply that I have yet feen, it being (bmewhat inclining towards the make of the large Dragon-Flies. Next, becaufe there is a greater variety in the knobs or balls of each clufteiythen is of any fmall Pd\ ) Then examining it according to my ukial manner, by varying the degrees of light, and altering its pofition to each kinde of light, I drew that reprefentation of it which is delineated in the 24. Scheme^ and found thefe things to be as plain and evident, as notable and pleafant.
Firf^ that the greatefl: part of the face,nay,of the head, was nothing elfe but two large and frotuberunt bunches, orpr<?/?/7»c;;/parts, A B C D E Ajtlre furface of each of which was all cover’d oyer, or fhap’d into a multitude of (mall Ften/ijpheres ^plac’d in a order, that being the cloleh: and mo(f Gompafted, and in that order, rang’d over the whole furiaceofthe eye in very lovely rowsFetween each of which^ as is ncceflary, were left long and regular trenches, the bottoms of every of which, were perfcftly intire.and not at all perforated or drill’d through, which I mofi: certainly was allured of, by tire regularly rehe^ed Image of certain Objeds which I mov’d to and fro between the head and the light. And by examining the Cornea or outward (kin, after I had ftript it off from the (everal fub- (fances that lay within ir,and by looking both upon the inlide and againd: the light.
Fiext^ that of thofe multitudes of Hemifphcres^ there were obfervable two degrees of bignefs,the half of them that were lowermodjand look’d toward the ground or their own leggs, namely, C D E, C D E being a pretty deal fmaller then the other, namely, A B C E, A B C E, that look’d upward, and (ide-waySjOr foreright, and backward, which variety I have not found in any other fmall Fly.
Fhirdly^ that every one of the(e Flemijpheres^zs they feem’d to be pret- ty neer the true (hape of a Hemifphere^ fo was the (urface exceeding (mooth and regular, reflefting as exad, regular, and perfed an Image of any Ob jed from the furface of them, as a fmall Ball of Quick-filver of that bignels would do, but nothing neer (b vivid, the refiedion from thefe being very languid, much like the refledion from the outlide of Water, Glafs, Cryftal, In (b much that in each of thefe Heniijpheres, I have been able to difeover a Land-(cape of thofe things which lay before my
window.
Ml CROGR AP HI A.
window, one thing of which was a large Tree, whofe trunk and top I .could plainly difcover, as I could alfo the parts of my window, and my hand and fingers, if I held it between the Window and the Objed^ a finall draught of nineteen of which, as they appear’d in the bigger Mag- nifying-glafs to rcfled the Image of the two windows of my Chamber, are delineated in the third figure of the 23. Scheme. >
Fourthly j that thefe rows were fo difpos d, that there was no quarter vifible from his head that there was not Tome of thefe Hemijphcres direded againft 5 fo that a Fly may be truly laid to have au eye every way^ and to be really circumfpeB. And it was further oblervable, that that way where the trunk of his body did hinder his profped backward, thefe protube- rances were elevated, as it were, above the plain of his fhoulders and back, lb that he was able to fee backwards allb over his back.
Fifthly^ in living Flies, I have obferv’d, that when any (mail mote or dufl:, which dies up and down the air, chances to light upon any part of thefe knobs, as it is lure toftick firmly to it and not fall, though through the Microfcope it appears like a large ftone or flick (which one would ad- mire,efpecially fince it is no ways probable that there is any wet or gluti- nous matter upon thefe Hemijpheres^hut I hope I fhall render the reafon in another place) fo the Fly presently makes ufe of his two fore-feet in ftead of eye-lids, with which , as with two Brooms or Brufhes, they 'being all beftuck with Brifles, he often Iweeps or brulhes off what ever hinders theprolpedl: of any of hi§ Hemijpheres^ and then, to free his leggs from that dirtjhe rubs them one againft another. the pointed Brilles or Tenters of which looking both one way, the rubbing of them to and fro one againft another, docs cleanle them in the fame manner as I have obferv’d thole that Card Wool, to cleanfe their Cards, by placing their Cards, lb as the teeth of both look the fame way,and then rubbing them one againft another. In the very lame manner do they brulh and cleanle their bodies and wings, as 1 fhall by and by Ihew , other creatures have other contrb vances for the cleanfing and cleering their eyes.
Sixthly^ that the number of the Pearls or Hemijpheres in the clufters of this Fly, wasneer 14000. which I judged by numbering certain rows of them leveral ways, and calling up the whole content , accounting each clufter to contain about feven thouland Pearls, three thou land of which were of a cize, and confequently the rows not fo thick, and the fbure thoufand I accounted to be the number of the fmaller Pearls next the feet and probofek. Other Animals I oblerv’d to have yet a greater number, as the Dragon-Fly or Adderbolt : And others to have a much lels company, as an Ant^ &c. and feveral other fmall Flies and Infefts.
Seventhly yhzt the order of thele eies or Hemijpheres was altogether curi- ous and admirable,they being plac’d inall kind ofFlies,and animals, in a moft curious and regular ordination of triangular rows, in which or- der they are rang’d the neereft together that poflibly they can, and con- fequently leave the leaf! pits or trenches between them. But in shrimps^ CraTpJiJhesy Lobjiers^ and fuch kinds of Crufiaceous water Animals, I have
yet
M,I CROGRAPHlA.
177
yet oblerv’d them rang’d in a quadrangular order, the rows cutting each other at right anglesjwhich as it admits of a lefs number of Pearls in equal furfaces , fo have thofe creatures a recompence made them, by having their eyes a little movable in their heads, which the other altogether want. So infinitely wife and provident do we find all the Dilpenlations in Nature, that certainly Epicurus^ and his followers, muft very little have confider’d them, who aferib’d thole things to the production of chance, that wil.to a more attentive confiderer, appear the products of the higheft Wildom and Providence.
Uponthe Anatomy or DifleCtion of the Head, I obferv’d thele par- ticulars :
Firft, that this outward Ikin, like the Cornea of the eyes of the greater Animals, was both flexible and tranlparent, and feem’d, through thei!/i- crojeope^ perfectly to relemble the very lubltance of the Cornea of a man’s eye 5 for having cut out the clutter, and remov’d the dark and mucous Ituff that is fubjacent to it, I could lee it tranfparent like a thin piece of Ikin, having as many cavities in the infide of it, and rang’d in the lame order as it had protuberances on the outlide,and this propriety,! found the fame in all the Animals that had it, whether Flies or Shell-Filh.
Secondly, I found that all Animals that I have obferv’d with thofe kind of eyes, have within this Cornea^ a certain deer liquor or juice, though m a very little quantity, and,
I obferv’d thirdly, that within that deer liquor, they had a kind of dark mucous lining, which was all fpread round within the cavity ofthe duller, and feem’d very neer adjoining to it, the colour of which, in fome Flies, was grey 5 in others, blacky in others red ^ in others,of a mix’d colour i in others,fpottcd ^ and that the whole cluflers, when look’d on whirif the Animal was living, or but newly kill’d, appear’d of the fame colour that this coat (as I may lb call it) appear’d of, when that outward Ikin, or CorneapN^s remov’d.
Fourthly, that the relt of the capacity of the cluflers was in fome, as in Dragon Flies, hollow, or empty; in others fill’d with Ibmekind of lubftance ; in blue Flies,with a reddilh mufculous lubflance, 'wtxh fibres tending from the center or bottom outwards ; and divers other, with va- rious and differing kinds oflubflances.
That this curious contrivance is the organ of fight to all thofe various Crufiaceous Animals, which are furnifh’d with it, I think we need not doubt, if we confider but the feveral congruities it has with the eyes of greater creatures.
Asfirfl, that it is furnifh’d with a Corneapm^ a tranjparent humour^^nd with a uvea or retina^ that the Figure of each of the Imall Hemijpheres are very Spherical^ exaftly polilh’d, and mofl vivid, lively and plump,when the Animal is living,as in greater Animals,and in like manner dull,flaccid, and irregular, or fhrunk,when the Animal is dead.
Next, that thofe creatures that are furnilh’d with it, have no other organs that have any relerablance to the known eyes of other creatures.
B b
Thirdly,
178
MiCROGR AP Hi A.
Thirdly jthat thofe which they call the eyes of CrabsjLobfterSjShrimp?, and the like, and are really fo, are Hemijpherd, almoft in the fame man- ner as thefe of Flies are. And that they really are lb, I have very often try’d, by cutting off thefe little movable knobs, and putting the creature again into the water, that it would fwim to and fro, and move up and down as well as before, but would often hit it felf againft the rocks or ftonesj and though I put my hand juft before its head, it would not at ^11 ftart or fly back till I touch’d it, whereas whifft thofe were remain- ing, it would ftart back,and avoid my hand or a ftick at a good diftancc before it touch’d it. And if in crujiaceous Sea-animals, then it leemsvery probable alfo,that thefe knobs are the eyes in cruJiaceous\t\(e(kSy which are alfo of the fame kind, onely in a higher and more aftive Element , this the conformity or congruity of many other parts common to either of them, will ftrongly argue,their crujiaceous armour,their number of leggs,which are fix, befide the two great claws, which anfwer to the wings in Infers 5 and in all kind of Spiders, as alfb in many other Infedfs that want wings, we fl:all find the compleat number of them, and not onely the number, but the very fhape, figure, joints, and claws of Lobfters and Crabs, as is evident in Scorpions and Spiders, as is vifible in the fecond Figure of the 5 i.Scheme^sind in the little Mite-worm,which I call a Land-crab,delcrib’d in the fecond Figure of the 33. Scheme^but in their manner of generation being oviparous, €^c. And it were very worthy obfervation, whether there be not fomc kinds of transformation and metamorphofis in the fe- vcral ftates of crujiaceous water-animals, as there is in fevcral forts of In- fers 3 for if fuch could be met with,the progrefs of the variations would be much more confpicuous in thofe larger Animals, then they can be in any kind of Infedcs our colder Climate affords.
Thefe being their eyes, it affords us a very pretty Speculation to con- template their manner of vifion, which, as it is very differing from that of biocular Animals, fb is it not left admirable.
That each of thefe Pearls or Hemijpheres is a perfedt eye, I think we need not doubt, if we confider onely the outfide or figure of any one of them, for they being each of them cover’d with a tranfparcnt protube- rant Cornea^ and containing a liquor within them, refembling the watry or glafiie humours of the eye, muft neceflarily refradt all the parallel Rays that fall on them out of the air, into a point not farr diftant within them, where (in all probability) the Retina of the eye is placed,and that opacous, dark, and mucous inward coat that (I formerly fhew'd) I found to fubtend the concave part of the clufter is very likely to be that tu~ nick or coat, it appearing through the Microjeope to be plac’d a little more than a Diameter of thofe Pearls below or within the tunica cornea. And if fo, then is there in all probability, a little Pidfure or Image of the objedts without, painted or made at the bottom of the Retina againft every one of thofe Pearls, fo that there are as many impreflions on the Retina or opacous fkin, as there are Pearls or Hemijpheres on the clufter. But becaufe it is impolfible for any protuberant furface whatfbever, whe- ther Jpharial or other, fo to refradl the Rays that come from farr remote
lateral
X
ICROGKAPHIA*
lateral points of any Objed as to colled them again^and unite them each in a diftind point^and that onely thofe Rays which come from fome point that lies in the Axis of the Figure produc'd, are fo accurately re- fraded to one and the lame point again, and that the lateral Ray s,thefur- thcr they are remov’d, the more imperfed is their refraded confluence y It follows therefore, that onely the Pidure of thole parts of the external ^ objeds that lie in, or neer, the Axis of each Hemijphere^ are dilcernably painted or made on the Retina of each Hemijphere^ and that therefore each of them can dift indlyfenfate or fee onely thofe parts which are very i neer perpendicularly oppos’d to it, or lie in or neer its optick Axis.
\ Nowj though there may be by each of thefe eye-pearls,a reprefentation to the Animal of a whole Hcmijfhere in the fame manner as in a man’s eye there is a pidure or fenfation in the Retina of all the objeds lying almoft in an Hemifphcre 5 yet, as in a man’s eye alfo, there are but fome very few points which liyng in, or neer, the optick Axis are diftindly dif- cern’d : So there may be multitudes of Pidures made of an Objed in the feveral Pearls, and yet but one, or fome very few that are diflind 5 The reprefentation of any objed that is made in any other Pearl, but that which is diredly,or very neer diredly,oppos’d,being altogether confus’d and unable to produce a diftind vifion.
So that we fee, that though it has pleas’d the All-wife Creator, to in- due this creature with fuch multitudes of eyes, yet has he not indued it ' ' with the faculty of feeing more then another creature, for whereas this ! cannot move his head,at leaft can move itvery little,without moving his ; ( whole body, biocular creatures can in an inftant (or the twinkling of an I eye^ which, being very quick, is vulgarly ufed in the fame fignification} i move their eyes fo as to dired the optick Axis to any point 5 nor is it
I probable, that they are able to fee attentively at one time more then one
i Phyfical point ; for though there be a diftind Image made in every eye,
' yet ’tis very likely, that the obferving faculty is only imploy ’d about fome
one objed for which they have moft concern.
Now, as we accurately diftinguifti the fite or pofition of an Objed by the motion of the Mufoles of the eye requifite to put the optick Line in a dired pofition,and confufedly by the pofition of the imperfed Pidure of the objed at the bottom of the eye 5 fo are thefo crufaceous creatures able to judge confufedly of the pofition of objeds by the Pidure or im- preflion made at the bottom of the oppofite Pearl, and diftindly by the removal of the attentive or obferving faculty, from one Pearl to another, but what this faculty is^as it requires another place, fo a much deeper fpe-' culation. Now,becaufeit were impofiible,even with this multitude of eye- balls,to fee any objed diftind(for as I hinted before, onely thofe parts that lay in,or veryneer,the optick Lines could be fo)the Infinitely wife Creator has not left the creature without a power of moving the head a little in Aerial crujiaceous animals,and the very eyes alfo in crujiaceous Sea-animalsg .fo that by thefe means they are inabled to dired fome optick line or other againft any objed,and by that means they have the vifive faculty as com- pleat as any Animal that can move its eyes.
B b 2
Diftances
i8o
M I C R O G R A P H I A.
Diftances of Objefts alfo, ’tis very likely they diftinguilh, partly by the conlbnant impreflions made in fome two convenient Pearls, one in each clufter , for, according as thofc congruous impreflions affedi:, two Pearls neerer approach’d to each other, the neerer is the Objedi:^ and the farther they are diftant, the more diftant is the Objedl: : partly alfo by the alteration of each Pearl, requifite to make the Senfation or Pidture perfedt 5 for ’tis impoflible that the Pidlures of two Objedis, varioufly diAant, can be perfedtly painted, or made on the fame Retina or bottom of the eye not altered, as will be very evident to any one that fliall atten- tively confider the nature of refraftion. Now, whether this alteration may be in the Figure of the Cornea^m the motion of acceis or recels of the Retina towards the Cornea^ or in the alteration of a cruAaline humour, if filch there be, I pretend not to determine , though I think we need not doubt, but that there may be as much curiofity of contrivance and Aru- diure in every one of thele Pearls, as in the eye of a Whale or Elephant, and.thejalmighty’s Riat could as eafily caufe the exiAence of the one as the others and as one day and a thoufand years are the fame with him,lb may one eye and ten thoufand.
This we may be fiire of, that the filaments or fenfative parts of the Retina muA be moA exceedingly curious and minute, fince the whole Pidture it fclf is fuch 5 what muA needs the component parts be of that Retina which diAinguifhes the part of an ob jedf s Pidture that muA be many millions of millions lels then that in a man’s eye ? And how exceed- ing curious and fubtile muA the component parts of the medium that conveys light be, when we find the inArument made forks reception or refradtion to be fo exceedingly fmall ? we may, I think, from this fpecula- tion be fiifBciently difeouraged from hoping to difeover by any optick or other inArument the determinate bulk of the parts of the medium that conveys the pulfe of light, fince we find that there is not lefs accuratc- nefs fhewn in the Figure/ and polifli of thofe exceedingly minute lenti- cular furfaces, then in thofe more large and confpicuous furfaces of our own eyes. And yet can I not doubt, but that there is a determinate bulk of thofe parts, fince I find them unable to enter between the parts of Mercury, which being in motion, muA neceflarily have pores, as I fliall elfewhere flievv, and here pafs by, as being a digreflion.
As concerning the horns F F, the feelers or fmellers, G G, the Vro- bafeis H H, and I, the hairs and brifles, K K, I fhall indeavour to de- Icribe in the 42. Objervation.
Obferv. X L. Of the Teeth of a Snail.
J Have little more to add of the Teeth of a Snail, befides the Pidlure of it, which is reprefented in the firA Figure of the 25. Scheme^ fave- that his bended body, A B C D E F, which feem’d fafhioned very much like a row of fmall teeth, orderly plac’d in the Gums, and looks as if it
were
Micrograph! Ai l8l
were divided into levcral fmaller and greater black teeth^ was nothing but one fmall bended hard bone^ Which was plac'd in the upper jaw of the mouth of a Honle-Snail, with which I oblcrv’d this very Snail to feed on the leaves of a Rofe-treej and to bite out pretty large and half round bits, not unlike the Figure of a ( C ) nor very much differing from it in bignefs, the upper part A B C D of this bone,*I found to be much whiter, and to grow out of the upper chap of the Snail. G G G,and not to be any thing neer fo much creas’d as the lower and blacker part of it H 1 1 H K K H which was exadly fhap’d like teeth, the bone growing thinner, or taper- ing to an edge towards K K K. It Teem’d to have nine teeth, or prominent parts I K, I K, I F, ^c. which were join’d together by the thinner inter- pos’d parts of the bone. The Animal to which thele teeth belong, is a very anotnalouT creature, and feems of a kind quite diftind from any other terreffrial Animal or Inled,the Anatomy whereof exceedingly dif- fering from what has been hitherto given of it I fhould have inferted, but that it will be more proper in another place. I have never met with any kind of Animal whofe teeth are all join’d in one, fave onely that I lately obferv’d, that all the teeth of a RhinocerOt, which grow on either fide of its mouth, are join’d into one large bone, the weight of one of which rfound to be neer eleven pound Haverdupois. So that it feems one of the biggeft fort of terreftrial Animals, as well as one of the fmalleft, has his teeth thus fhap’d.
. Obferv. X LI. Of the Eggs ofSiW-wovms^aTtJ other Infers.
THe Eggs of Silk-worms(one of which I have deferib’d in the fecond Tighre of 25. Scheme) afford a pretty Objed for a Mkrofeope that magnifies very much, efpecially if it be bright weather, and the light of a window be caft or colleded on it by a deep Convex-glaJ^^ or Water-ball. For then the whole furface of the Shell may be perceiv’d all cover’d over with exceeding fmall pits or cavities with interpofed edges, almoft in the manner of the furface of a Poppy-feed,but that thefe holes are not an hun- dredth part fcarce of their bignefs, the Shell, when the young ones were hatch’d (which I found an eafie thing to do, if the Eggs were kept in a warm place) appear’d no thicker in proportion to its bulk,then that of an Hen’s or Goos’s Egg is to its bulk,and all the Shell appear’d very white (which feem’d to proceed from its tranfparency) whence all thofe pit- tings did almoft vanifh, fb that they could not, without much difficulty,A be difcern’d,the infide of the Shell feem’d to be lin'd alfo with a kind of thin film,not unlike (keeping the proportion to its Shell)that with which the Ihell of an Hen-egg is lin’d 5 and the fhell it felf feem’d like common Egg-fhells, very brittle, and crack’d. In divers other of thefe Eggs I could plainly enough, through the fhell, perceive the fmall Infed: lie coyled round the edges of the (helh The fhape of the Egg it felf, the Figure pretty wellreprefentsCthoughby default of the Graver it docs
not
i82
Micrographia.
not appear fo rounded, and lying above the Paper, as it were, as it ought to do) that is, it was for the moft part pretty oval end-ways, fomewhat like an Egg,but the other way it was a little flatted on two oppofite fides. Divers of thefe Eggs, as is common to moft others, I found to be bar- ren, or addle, for they never afforded any young ones. And thole I ulually found much whiter then the other that were prolifick. The Eggs of other kinds of Oviparous Infefts I have found to be perfe^ly round every way,like fo many Globules, of this fort I have obferv’d fome forts of Spiders Eggs 5 and chancing the laft Summer to inclofe a very- large andcurioufly painted Butterfly in a Box, intending to examine its gaudery with my Microfeope^ I found within a day or two after I inclos’d her, almoft all the inner furface of the Box cover’d over with an inffnite of exadtly round Eggs, which were ftuck very faft to the fides of it, and in fo exactly regular and clofe an order, that made me call to mind my Hj/pothefis^ which I had formerly thought on for the making out of all the regular Figures of Salt, which I have elfewherc hinted 3 for here I found all of them rang’d into a moft exadt triagonal order, much after the man- ner as the Hemijpheres are place on the eye of a Fly 5 all which Eggs I found after a little time to be hatch’d, and out of them to come a multi- tude of fmall Worms, very much refembling young Silk-worms, leaving all their thin hollow Ihells behind them, fticking on the Box in their tn- Agonal pofture 5 thefe I found with the Microfeope to have much luch a lubftance as the Silk-worms Eggs, but could not perceive them pitted. And indeed, there is as great a variety in the ffiape of the Eggs of Ovi- parous Infedts as among thofe of Birds.
Of thefe Eggs, a large and lufty Fly will at one time lay neer four or five hundred, fo that the increafo of thefe kind of Infodls muft needs be very prodigious^ were they not prey’d on by multitudes of Birds, and de- ftroy’d by Frofts and Rains 5 and hence ’tis thofe hotter Climates between the Tropicks areinfefted with fuch multitudes of Locufts, and fuch other Vermine.
Obferv. X L 1 1. Of a blue Fly,
T His kind of Fly,whereofa MicrofcopicalVxCioiQ is delineated in the firft Figure of the 26. Scheme^ is a very beautiful 1 creature, and has many things about it very notable 3 divers of which I have already partly deferib’d, namely, the feet, wings, eyes, and head, in the preceding Oblervations.
And though the head before deforib’d be that of a grey Drone-Fly^ yet for the main it is very agreeable to this. The things wherein they differ moft, will be eafily enough found by the following particulars : Firft, the clufters of eyes of this Fly, are very much fmaller then thofe of the Dron'-Fly^ in proportion to the head.
And
I
MXX
1-
!
- ^ E ^
Micrographi a.
And "next, airthe eyes of each clufter feem’d much of the lame bignefs one with another, not differing as the other, but rang’d in the fame?r>=- agon/il order.
. Thirdly, between thefe two clufters, there was a fcaly prominent front B, which was arm’d and adorn’d with large tapering fharp black brifles, which growing out in rows on either fide, were fo bent toward each other neer the top, as to make a kind of arched arbour of Brifles, which almoft cover’d the former/r<?«r.
Fourthly, at the end of this Arch, about the middle of the face, on a prominent part C, grew two ffnall oblong bodies^ D D, which through a Microfcope look’d not unlike the Pendants in Lillies, thefe feem’d to be jointed on to two fmall parts at C, each of which feem’d again jointed into the front.
Fifthly, out of the upper part and outfides of thefe horns (as I may call them, from the Figure they are of, in the 24. Scheme ^ where they are marked with F F) there grows a Angle feather, or brufhy Brifle, E fomewhat of the fame kind with the tufts of a Gnat, which 1 have before defcribed.
What the ufe of thefe kind of horned and tufted bodies fhouldbe, I cannot well imagine,unlels they ferve for fmelling or hearing, though how they arc adapted for either, it foems very difficult to defcribe they, are in almofl: every feveral kind of Flies of fo various a fhape; though certain- ly they are fbme very eflential part of the head, and have fbme very notable office aflign’d them by Nature, fincein all Infeds they are to be found in one or other form. r
Sixthly, at the under part of the face F F, were feveral of the former fort of bended Brifles, and below all,, the mouth, out of the middle of which, grew the probofck G H I, which,by means of feveral joints, where- of it feem’d to confiff, the Fly was able to move to and fro, and thruft it in and out as it pleas’d , the end of this hollow' body (which was all over cover’d with fmall fhort hairs or brifles) was, as ’t were, bent at FI, and the outer or.formoft fide of the bended part H I, flit, as it were, into two chaps, H I, H I, all the outfide of which where cover’d with hairs, and pretty large briflesy thefo he could, like two chaps, very readily open and fhut, and when he feem’d to fuck any thing from the forface of a body, he would fpread abroad thofe chaps, and apply the hollow part of them very clofo to it.
From either fide of the Trobofeis^ within the mouth, grew two other fmall horns, or fingers, K K, which were hairy, but fmall in this Figure 5 but of another fhape, and bigger in proportion, in the 2 Scheme^ w\\qxq they are marked with G G, which two indeed feem’d a kind of fmellers, but whether fo or not, I cannot pofitively determine^
The Thorax or middle part of this Fly, was cas’d, both above and be- neath, with a very firm cruft of armour, the upper part more round, and covered over with long conical brifles,all whole ends pointed backwards, out of the hinder and under part of this grew put in a clufter ;fix leggs, three of which are apparent in the Figure, the other three were hid by the
Ml CROGRAHP 1 A.
body plac’d in that pofture. The leggs were all much of the fame make, being all of them cover’d with a ftrong hairy fcale or {hel,)uft like the legs of a Grabb or Lobfterjand the contrivance of the joints feem’d much the fame 5 each legg feem’d made up of eight parts, i, 2, 5, 4, 5, 6, 7, 8, to the eighth or laft of which, grew the foies and claws, described before in the 38. Objervation,
Out of the upper part of this trunck grew the two wings, which I men- tion'd in the 38. Objervation^ confifting of a film, extended on certain (mall ftiff wires or bones : thefe in a blue Fly, were much longer then the body, but in other kind of Flies they are of very differing propor- tions to the body. Thele films,in many Flies,wcre fo thin,that,like feveral other plated bodies (mention’d in the ninth Obfervation) they afforded all varieties offantaftical or tranfient colours (the realbn of which I have here endeavoured to explain) they feem’d'to receive their nouriffiment from the ftalks or wires, which feem’d to be hollow, and neer the upper part of the wing L L feveral of them feem’d jointed, the fhape of which will fufiiciently appear by the black lines in the fecond Figure of the 26. Scheme^ which is a delineation of one of thofe wings expanded di- reftly to the eyes.
All the hinder part of its body is cover’d with a moft curious blue flii- ning armour,looking exadfly like a polifh’d piece of fteel brought to that blue colour by annealing, all which armour is very thick beftuck with abundance of tapering brifles, fuch as grow on its back, as is vifible enough by the Figure.
Nor wastheinfide of this creature Icfs beautifull then itsoutfide, for cutting off a part of the belly, and then viewing it, to lee if I could dif- cover any Veflels, fuch as are to be found in a greater Animals, and even in Snails exceeding manifeftly,! found,much beyond my expedi:ation,that there were abundance of branchings of Milk-white veffds,no lefs curious then the branchings of veins and arteries in bigger terreffrial Animals, in one of which,! found two notable branches, joining their two main ftocks, as it were, in to one common du&us 5 now, to what veins or arteries thefe Vellclls were analogus^ whether to the vena porta^ or the meferaick^ vej^ Jedsj or the like, or indeed, whether they were veins and arteries, or v<Ja properly lb called, I am not hitherto able to determine, having not yet made fuflicient enquiry 5 but in all particulars, there feemsnqt to be any thing lefs of curious contrivance in thefe Infers, then in thofe larger terreffrial Animals, for I had never feen any more curious branch- ings of VefTel Is, then thofe I obferv’d in two or three of thefe Flies thus opened.
It is a creature affive and nimble, lb as there are very few creatures like it, whether bigger orffnaller, in fo much, that it will ieape and avoid a^fmall body, tteugh coming on it exceeding fwiftly, and ifit fees anythingapproachingit, which it fears, it prefently fquats dowfi, as it were,that it may be the more ready for its rife.
Nor is it lefe hardy in the Winter, then affive in the Summer, induring allthcFtofts, and forviving till thc-next Summer, notwithffanding the
bitter
/
T^^-85'- ' Schem.YXyn .
I
Micrographia.
bitter cold of our Climate 3 nay, this creature will indure to be frozen, and yet not be deftroy’d,for I have taken one of them out of the Snow whereon it has been liozen almofl white, with the Ice about it, and yet by thawing it gently by the warmth of a fire, it has quickly reviv'd and flown about.
This kind of Fly feems by the fleams or tafle of fermenting and putrifying meat (which it often kiflb,as’twere, with its probofds as it trips over it) to be ftimulated or excited to ejedt its Eggs or Seed on it, per- haps, from the fame reafon as DogSjCatSjand many other brute creatures are excited to their particular lufts, by the fmell of their females, when by Nature prepared for generation ^ the males feeming by thofe kind of fmells, or other incitations, to be as much neceffitated thereto, as Jquu Regis flrongly impregnated with a folution of Gold,is forced to pre- cipitate it by the affufion of fpirit of Urine^ or a folution of Salt of Tartar.
One of thefe put in fpirit of Wine^ was very quickly feemingly kill' d, and both its eys and mouth began to look very red, but upon the taking of it out, and fufferingit to lie three or four hours, and heating it with the Sun beams cafl through a Burning-glafs, it again reviv'd, feeming, as h: were, to have been all the intermediate time, but dead drunk, and af- ter certain hours to grow frefh again and fober.
Obferv. X L H I. Of the Water-InfeQ: or Gnat.
T His little creature, defcribed in the firfl Figure oi'the Scheme^ was a fmall flaled or crufled Animal, which I have often obfcrv'd to be generated in Rain-water 5 1 have alfo obferv’d it both in Pond and River-water. It is fuppos’d by fome, to deduce its firfl original from the putrifadtion of Rain- water, in which, if it have flood any time open to the air, you fliall feldom mifs,all the Summer long, of flore of them frifking too and fro.
'Tis a creature, wholly differing in fhape from any I ever oblerv’d 5 nor is its motion lefsflrange: It has a very large head, in proportion to its body, all covered with a Ihell, like other tejiaceous Animals, but it dif- fers in this, that it has, up and down feveral parts of it, feveral tufts of hairs, or brifles, plac'd in the order exprefs'd in the Figure 5 It has two horns, whichleem’d almofl like the horns of an Oxe,inverted,and, as neer as I could ghefs,were hollow, with tufts of brifles,likewile at the top^thefe horns they could move eafily this or that way,and might, perchance, be ^ their noflrils. It has a pretty large mouth, which feem’d contriv’d much : like thole of Crabs and Lobflers,by which, I have often obferv'd them to
feed on water, or fome imperceptible nutritive fubflance in it.
I could perceive, through the tranfparent fhell,while the Animal iur- I viv'd, feveral motions in the head, thorax, and belly, very diftindlly,
C c of
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Micrographia.
of differing kinds which I may, perhaps^ elfewhere endeavour more ac- curately to examine, and to fhew of how great benefit the uleofa Mi- crofcope may be for the difcovery of Nature’s courfe in the operations per- form’d in Animal bodies, by which we have the opportunity of obferving her through thefe delicate and pellucid teguments of the bodies of Infedts adting according to her ufual courfe and way, undifturbed, whereas, when we endeavour to pry into her fecrets by breaking open the doors upon her, and difledfing and mangling creatures whil’d there is life yet within them, we find her indeed at work, but put into fuch diforder by the violence offer’d, as it may eafily be imagin’d^how differing a thing we fhould find, if we could,as we can with a Microfeope^m thefe fmaller crea- tures, quietly peep in at the windows, without frighting her out of her ufual byas.
The form of the whole creature, as it appear’d in the Microfeope^ ni^y, without troubling you with more deferiptions, be plainly enough per- ceiv’d by the Scheme^ the hinder part or belly confiding of eight feveral jointed parts, namely, ABCDEFGH, of the fird Figure^ from the midd of each of which,on either fide,idued out three or four fmall brides or hairs, I, I, I, T, I, the tail was divided into two parts of very differing make one of them, namely, K, having many tufts of hair or brides, which feem’d to ferve both for the finns and tail, for the Oars and Ruder of this little creature, wherewith it was able, by frifking and bending its body nimbly to andfro,to move himfelf any whither, and to fkull and deer hira- felfas he pleas’d^the other part, L, Teem’d to be, as ’twcre,the ninth divifi- on of his belly,and had many fingle brides on either fide. From the end V, of which, through the whole belly, there was a kind of Gut of a darker colour, M M M, wherein, by certain Perijialtick^monons there was a kind of black fubdance mov’d upwards and downwards through it from the orbicular part of it, N, (which feem’d the F(?/?/m7e,or domach)to the tail V,and To back again, wh\chperiJialtic/{^ motion I have obferv’d alfb in a Loufe, a Gnat, and feveral other kinds of tranfparent body’d Flies. The Thorax or ched of this creature O O O O, was thick and fhort, and pret- ty tranfparent, for through it I could fee the white heart (which is the colour alfb of the bloud in thefe, and mod other Infeds) to beat, and feveral other kind of motions. It was beduck and adorn’d up and down with feveral tufts of brides, fuch as are pointed out by P, P, P, P, the head CLwas likewife beduck with feveral of thofe tufts, S S S5 it was broad and fhort, had two black eyes, T T, which I could not perceive at all pearl’d, as they afterwards appear’d, and two fmall horns, R R, fuch as I formerly deferib’d.
Both its motion and red is very drange, and pleafant, and differing from thofe of mod other creatures I have obferv’d ; for, where it ceafes from moving its body, the tail of it Teeming much lighter then the red of its body,and a little lighter then the water it fwims in, prefently boys it up to the top of the water, where it hangs fufpended with the head al- ways downward , and like our Antipodes^ if they do by a frifk get be- low that fuperficies, they prefently afeend again unto it, if they ceafe
moving,
MiCROCJRAPHiAi
moving, until they tread, as it were, under that (uperficies with their tails 5 the hanging of thele in this pofture, put me in mind of a cer** tain creature I have feen in London^ that was brought out of America^ which would Very firmly fufpend it lelf by the tail, with the head down- wards,and was faid to lleep in that pofture, with her young ones in het falfe belly, which is a Purfe, provided by Nature for the produftion, nutrition, and prefervation of her young ones, which is defcribed by Pijb in the 24. Chapter of the fifth Book of his Natural Hiftory of Brafl.
The motion of it was with the tail forwards, drawing its felf backwards, by the frifking to and fro of that tuft which grew out of one of the ftumps of its tail. It had another motion,which Was more futable to that of other creatures, and that is, with the head forward 5 for by the moving ofhischaps(”ifI may fo call the parts of his mouth) it was abletomove it felf downwards Very gently towards the bottom, and did, as twere,eat up its Way through the water.
But that which was moft oblervable in this creature. Was, its Meta- morphofis or change;for having kept feveral of thele Animals in a Glafs of Raimwater,in which they Were produc’d, I found ,after about a fortnight or three weeks keeping, that leveral of them flew away in Gnats,leaving their hulks behind them in the water floating under the furface, the place where thefe Animals Were V^ont to relide, whifft they were in- habitants of the water : this made me more diligently to watch them, to fee if I could find them at the timebf their transformation 5 and not long after, I oblerv’d feveral of them to be changed into an unulual Ihape, wholly differing from that they were of before, their head and body be- ing grown much bigger and deeper, but hot broader, and their belly, or hinder part Imaller, and coyf d , about this great body much of the fafhi- on reprelented by the prick’d line in the lecond figure of the 27. Scheme^ the head and horns now fwam uppermoft, and the whole bulk of the bo- dy fcem’d to be grown much lighter ^ for when by my frighting of it, it would by frilking out of its tail (in the manner exprefs’d in the Figure by B C) fink it lelf below the llirface towards the bottom 5 the body would more fwiftly re-afcend, then when it was in its former lhape.
I ftill marked its progrels from time to time,and found its body ftill to grow bigger and bigger. Nature, as it were, fitting and accoutring it for the lighter Element, of which it was now going to be an inhabitant 5, for,by oblerving one of thele with my Aiicrojcope^ I found the eyes of it to be altogether differing from what they leem’d before, appearing now all over pearl’d or knobb’d, like the eyes of Gnats, as is vifible in the fecong Figure by A. At length, I laW part of this creature to Iwim above, and part beneath the furface of the water, below which though It would quickly plunge it felf if I by any means frighted it,and prelently re-alcend into its former pofture , after a little longer expedadon, I found that the head and body of a Gnat,began to appear and ftand deer above the furface, and by degrees it drew out its leggs, firft the two for- tnoftjthcn the other,at length its whole body perfect and entire appear’d out of the hufk (which it left in the water) ftanding on its leggs upon
C c 2 the
i88
Micrographia.
the top of the water, and by degrees it began to move, and after flew about the Glafs a perfed Gnat.
I have been the more particular, and large in the relation of the tranft formation of divers of thefe little Animals which I oblerv’d, becauft I have not found that any Authour has oblerv’d the like 5 and becaule the thing it felf is fo ftrange and heterogeneous from the ufual progrefs of other Animals, that I judge it may not onely be pleafant, but very ulefull and neceflary towards the compleating of Natural Hiftory.
There is indeed in Pi/3, a very odd Hiftory, which this relation may- make the more probable 5 and that is in the 2. Chapter of the 4. Book of his Natural Hiftory of where he lays,Pf>rr<? ter tot documefttafer- tilitatis circa, vegetabilia ^ JenJitiva marina telluris (cmula^accidit illud^ quodpancis a Paranambucenfi milliaribus^pifcatoris uncunt citra intentionem contingat infigi vadis petrojis^d^ loco pijcisjpongia^coral/a^aliajque arbufculas marinas capi. Inter hcec inujitat£ formce prodit JpongioJa arbufcula^Jejquipedis longifndiniSy brevioribns radicibus^ lapideis nitens vadis, d" rupibus infixa^ erigiturqpte in corpus JjjongioJum moUe oblongum rotundum turbinatum: intus miris cancellis d' alvei s fabric atum^ extus autem tenaci glutine injiar Apum propolis undique vejlitum^ ojiio fatis patulo profundo in fimimitate reli^o.^ ficut ex altera iconum probe depi&a videre licet (fee the third and fourth Figures of the 27. Scheme.') It a ut Apiarium marinum vere dixeris '^primo enim intuitu h Mare ad Terr am delatum^vermiculis fcatebat c£ruleis parvis^ qui mox a calore filis inMujcas^vel Apes potius^eajq’.^ exiguas d“ nigras tranf- formebantur^ circumvolantefque evanefcebantdt<^ ut de eorum mellificatione nihil certi confpici datum fueritj cum t amen cwrofa materia propolis Apum- que cellce manifejie apparerent^atque ipfa mellis qualifcunque JubJlantiaprocul- dubio urinatoribus patebit^ ubi curiojius inquijiverint h<ec apiaria^ eaque in natali folo dF falo diverjis temporibus penitius lujirarint.
Which Hiftory contains things lufficiently ftrange to be confider’d, as whether the hulk were a Plant, growing at the bottom of the Sea before, of it lelf, out of whole putrifadion might be generated thele ftrange kind of Magots 5 or whether the feed of certain Bees, finking to the bottom, might there naturally form it lelf that vegetable hive, and take root 5 or, whether it might not be placed there by Ibme diving Fly 5 or, whether it might not be fome peculiar propriety of that Plant, whereby it might ripen or form its vegetable juice into an Animal fubftance 5 or, whether it may not be of the nature of a Sponge, or rather a Sponge of the nature of this, according to fome of thofe relations and/con jedures I formerly made of that body, is a matter very difficult to be determined. Butindeed,in this defcription,the Excellent Pijb has not been fufficiently particular in the letting down the whole proccls, as it were to be wilh’d : There are indeed very odd progrefles in the produdion of feveral kinds of Inleds, which are not lels inftrudive then pleafant, feveral of which, the diligent Goedartius has carefully oblerv’d and recorded, but among all his Obfervations, he has none like this, though that of the Hemerobins be fomewhat of this kind, which is added as an Appendix by Johannes Mey.
I have
M I C R O G R A P H f A<
I have, for my own particular, befides feveral of thofe mention’d by him, obferv’d divers other circumftances,perhaps, not much taken notice of^ though very common, which do indeed afford us a very coercive argu- ment to admire the goodnefs and providence of the infinitely wile Crea- tor in his mofi: excellent contrivances and difpenfations.I have ob(erv’d,af feveral times of the Summer, that many of the leaves of divers Plants have been lpotted,or, as it were fcabbed, and looking on the underfidcs.of thofe of them that have been but alitte irregular, I have perceiv’d them to be fprinkled with divers forts of little Eggs, which letting alone,! have found by degrees to grow bigger, and become litde Vyorms with.leggSj but ftill to keep their former places, and thofe places of the leaves,of their own accords, to be grown very protuberant upwards, and very hollow,; and arched underneath, whereby thofe young creatures are, as it were, flielter’d and houfed from external injury v divers leaves I have oblerv’d to grow and fwell fo farr, as at length perfefHy to inclofe the Animal, which, by other obfervations I have made, I ghefs to contain it, and be- come, as it were a womb to it, fo long, till it be fit and prepar’d to be tranflated into another Hate, at what time, like (what they fay of) Vi- pers, they gnaw their way through the womb that bred them 5 divers of thele kinds I have met with upon Goolberry leaves, Rofe^tree leaves. Willow leaves, and many other kinds.
There are often to be found upon Rofe-trees and Brier bufhes, little red tufts,which are certain knobs or excreicencies,growing out from the Rind, or barks of thole kinds of Plants, they are cover’d with ftrange kinds of threads or red hairs, which feel very loft, and look not unplea- fantly. In mofi: of thefe, if it has no hole in it, you lhall find certain little Worms, which I fuppofe to be the caufes of their produdion 5 for when that Worm has eat its way through, they, having performed what they were defign’d by Nature to do, by degrees die and wither away.
NoWjthe manner of their production,! luppofe to be thus 3 that the Al- wile Creator has as well implanted in every creature a faculty of know- ing what place is convenient for the hatching, nutrition, and prefervati- on of their Eggs and of-fprings, whereby they are ftimulated and direCfed to convenient places, which becom, as ’twere the wombs that perform thofe offices : As he has allb fuited and adapted a property to thofe places wherby they grow and inclofe thofe feeds, and having incloled them, provide a convenient nourilhment for them, butas foonas they have done the office of a womb, they die and wither.
The progrels of inclofure ! have often obferv'd in leaves, which in thole places where thofe feeds have been caft, have by degrees Iwell’d and inclos’d them, fo perfeCcly round, as not to leave any perceptible pafiage out.
From this lame caufe, I luppofe that Galls, Oak-apples, and feveral other productions of that kind, upon the branches and leaves of Trees, have their original ^ for if you open any of them, when almoft ripe, you lhall find a little Worm in them. Thus, if you open never fo many dry Galls, you lhall find either a hole whereby the Worm has eat its pafiage
out,
i$o M ICROGRAPHi A.
out, or if you find no paflage, you mayjby breaking or cutting the Gall, find in the middle of it a fmall cavityj and in it a fmall body, which does plainly enough yet retain a fhapCj to manifefc it once to have been a Worm, though it dy’d by a too early reparation from the Oak on which it grew,its navel-ftring,as twere,being broken off from the leaf or branch by which the Globular body that invelop'd it, received its nourifliment from the Oak.
And indeed,if we confider the great care of the Creator in the dilpen- lations of his providences for the propagation and increafe of the race,not onely of all kind of Animals, but even of Vegetables, we cannot chule but admire and adore him for his Excellencies, but we (hall leave off to admire the creature, or to wonder at the ftrange kind of afting in (everal Animals, which feem to favour lb much of realbn , it feeming to me moft manifefi:,that thole are but adiings according to their ftrudlures, and luch operations as fiich bodies, lb compos’d, muft necefiarily, when there are fuch and fuch circumftances concurring, perform ; thus,whenwe find Flies fwarming,about any piece offlelh that does begin a little to ferment^But- terflies about Colworts,and feveral other leaves,wliich will ferve to hatch and nourilh their young 3 Gnats, and feveral other Flies about the Wa- ters, and marilhy places, or any other creatures, feeking and placing their Seeds in convenient repofitories, we may, if we attentively confider and examine it, find that there are circumftances lufficient,upon the luppofals of the excellent contrivance of their machine,to excite and force them to aft after fuch or fuch a manner 3 thofe fteams that rife from thefe feveral places may, perhaps, let Icveral parts of thefe little Animals at work,even as in the contrivance of killing a Fox or Wolf with a Gun, the moving of a firing, is the death of the Animal 3 for the Beaft, by moving the flefh that is laid to entrap him, pulls the firing which moves the trigger, and that lets go the Cock which on the fteel ftrikes certain Iparks of fire which kindle the powder in the pann, and that prefently flies into the barrel, where the powder catching fire ratifies and drives out the bullet which kills the Animal 3 in all which aftions, there is nothing of intention or ratiocination to be aferib’d either to the Animal or Engine, but all to the ingenioulnels of the contriver.
But to return to the more immediate confideration of our Gnat ; We have in it an Inftance, not ufual or common, jOf a very fiange amphu hious creature, that being a creature that inhabits the Air, does yet pro- duce a creature, that for fbme time lives in the water as a Filh, though afterward (which is as ftrange) it becomes an inhabitant of the Air, like its Sire,in the form of a Fly. And this, me thinks, does prompt me to pro- pofe certain conjeftures, as Queries, having not yet had fufficient oppor- tunity and leifiire to anfwer them my felf from my own Experiments or Obfervations.
And the firft is. Whether all thofe things that we fuppofe to be bred from corruption and putrifaftion, may not be rationally fuppos d to have their origination as natural as thefe Gnats, who, ’lisvery probable, were firft dropt into this Water, in the form of Eggs. Thofe Seeds or
Egg^^
Micrograph! A.
Eggs muft certainly be very fmal], which fo ImaJl a creature as a Gnat yields, and therefore; we need not wonder that we find not the Eggs themfelves, home of the younger of them, which I have obferv’d, having not exceeded a tenth part of the bulk they have afterwards come to 3 and nextjl have obferved fome of thofe little ones which mulf have been gene- rated after the Water was inclofcd in the Bottle, and therefore moft pro- bably from Eggs, v/hereas thole creatures have been fuppos'd to be bred of the corruption of the Water, there being not formerly known any probable way how they lliould be generated.
A Iccond is, whether thefe Eggs are immediately dropt into the Water by the Gnats themfelves, or, mediately, are brought down by the falling rain 3 for it leems not very improbable,but that thofe Imall feeds of Gnats may (being, perhaps, of lb light a nature, and having fo great a propor- tion of furface to fo fmall a bulk of body) be ejeded into the Air, and fo, perhaps, carried for a good while too and fro in it, till by the drops of Rain it be walk’d out of it.
A third is, whether multitudes of thofe other little creatures that are found to inhabit the Water for fome time, do not, at certain times, take W'ing and fly into the Air, others dive and hide themfelves in the Earth, and fo contribute to the increafe both ofthe one and the other Element,
A good while lince the writing of this Defeription, I was prelented by Dodor Peter Ball^ an ingenious Member of the Royal Society a little Paper ofNuts, which he told me was lent him from a Brother of his out of the Countrey,from Mumhead in Devonjhire^ fome of them were loole, having been, as I fuppofe, broken off, others were ftill growing faff on upon the fides of a Ifick, which feem’d by the bark, pliablenefs of it, and by certain firings that grew out of it, to be Ibme piece of the root of a Tree 3 they were all of them dry’d, and a little Ihrivelfd, others more round, of a brown colour 3 their lhape was much like a Figg, but very much lmaller,lbme being about the bignels of a Bay-berry^others,and the biggeft, of a Hazel-Nut. Some of thefe that had no hole in them, I care- fully opened with my Knife, and found in them a good large round white Maggot, almofl: as bigg as a fmall Pea, which feem’d lhap’d like other Maggots, but Ihorter. I could not find them to move, though I gheft’d them to be alive, becaule upon pricking them witha Pinn, there w^ould if fue out a great deal of white mucous matter, which feem’d to be from a vo- luntary contradion of their fkin 3 their hulk or matrix confifted of three Coats,like the barks of Trees, the outerraofl: being more rough and Ipon- gie, and the thickefl:, the middleraofi: more clofe. hard^ white, and thin, the innermofi: very thin,feeming almofl:' like the fkin within an Egg’s fhell. The two outermofl: had root in the branch or flick, but the innermofl: had no fl:cm or procels, but was onely a fkin that cover’d the cavity of the Nut. All the Nuts that had no holes eaten in them, I found to con- i tain thefe Maggots, but all that had holes, I found empty, the Maggots,
1^2
Ml CROGRAHP I A.
it feemSj having eaten their way through, taken wings and flown away^ as this following account (which I receiv'd in writing from the lame per- fon, as it was fent him by his Brother) manifefts. In a mooriji) blacky Featy mouldy with fome fntall veins of whitifs yellow Sands ^ upon occafion of digging a hole two or three foot deep^ at the head of a Fond or Fool^ to Jet a Tree in^ at that depths were founds about the end of Odober 1663. in thofe very veins of Sand, thofe Buttons or Nuts, jiicljng to a little loofe flicks, ^ that is, not belonging to any live Tree, and fome of them alfo free by themfelves.
Four or five of which being then opend, fome were found to contvin live Infers come to perfection, moji like to flying Ants, if not the fame 5 in others, InfeCls,yet impcrJeCl, having but the head and wings form'd, the reji remaining a foft white pulpy Jubfiance,
Now,as this furnilhes us with one odd Hiftory more, very agreeable to what I before hinted, lb I doubt not, but were men diligent oblervers, they might meet with multitudes of the fame kind, both in the Earth and in the Water, and in the Air, on Trees, Plants, and other Vegetables, all places and things being,as it 'wtre.animarum plena. And I h^ve often, with wonder and plealltre,in the Spring and Summer-time, look'd clofe to,and diligently on, common Garden mould, and in a veryfmall parcel of it, found liich multitudes and diverfities of little reptiles,{cme in hulks,others onely creepers, many wing'd, and ready for the Air 5 divers hulks or ha- bitations left behind empty. Now, if the Earth of our cold Climate be lb fertile of animate bodies, what may we think of the fat Earth of hotter Climates } Certainly,the Sun may there, by its activity, caufe as great a parcel of Earth to fly on wings in the Air, as it does of Water in fteams and vapours. And what fwarms muft we fuppofe to be fent out of thofe plentifull inundations of water which are poured down by the fluccs of Rain in luch vaft quantities ? So that we need not much wonder at thole innumerable clouds of Locufts with which Africa, and other hot coun- tries are lb peltred, fince in thofe places are found all the convenient ^ caufesof their produdion, namely, genitors, or Parents, concurrent re- ceptacles or matrixes,and a luflicient degree of natural heat and moiflure.
I was going to annex a little draught of the Figure of thofe Nuts fent out of Devonfljire , but chancing to examine Mr. TarkiuJons Herbal for Ibmething elle, and particularly about Galls and Oak-apples, I found among no lelsthen 24. feveral kinds of excrelcencies of the Oak, which I doubt not,but upon examination,will be all found to be the matrixes of lb many leveral kinds of Infeds ^ I having obferv'd many of them my lelf to be lb, among 24.''leveral kinds, I fay,I found one delcribed and Figur’d diredly like that which I had by me,the Scheme is there to be leen,the de- Icription, becaufe but Ihort, I have here ad join’d Theatri Botanici trib,\6. chap. 2. There groweth at the roots of old Oaky in the Spring-time, and Jemetimes alfo in the very heat of Summer, a peculiar kjnd of Mufljrom or Excrefcence, call'd Uva QucvQm2i,jwelIing out of the Earth, many growing one clofe unto another , of the fafljion of a Grape , and therefore took, the name, the Oak-Grape, and is of a Furplifl) colour on the outfde.
Micrographia.
and white within like Milk^^ and in the end of Summer heconieth hard and woody. Whether this be the very lame kind, I cannot affirm, but both the Picture and Defcription come very neer to that I have, but that he feems not to take notice of thehollownefsor Worm, for which 'tis mod obfervable. And therefore ’tis very likely, if men did but take notice, they might find very many differing Species of thefe Nuts, Ovaries^ or Matrixes^ and all of them to have much the fame defignation and office. And I have very lately found feveral Kinds ofEx- crefcencies on 1 rees and Shrubs, which having endured the Winter, up- on opening them, I found mod: of them to contain little Worms, but dead, thofe things that contain’d them being wither’d and dry.
Obferv. XL IV. Of thetufted or BruJh-horndGmti
THis little creature was one of thofe multitudes that fill our Englijh air all the time that warm weather lafts, and is exadly of the fhape of thatlobferv’d to be generated and hatch’d out of thofe little Infeffs that wriggle up and down irr Rain-water. But, though many were of this form, yetlobferv’d others to be of quite 'Other kinds 5 nor were all of this or the other kind generated out of Water Infedts^ for whereas I obferv’d that thofe that proceeded from thofe Infed's were at their full growth, I have alfo found multitudes of the fame fhape,but much fmaller and tenderer feeming to be very young ones, creep up and down upon the leaves of Trees, and flying up and down in fmall duffers, in places very remote from water f and this Spring, I obferv’d one day, when the Wind was very calm, and the afternoon very fair, and prdty warm, though it had for a long time been very cold weather, and the wind con- tinued ffill in the Eaff, feveral fmall fwarms of them playing to and fro in little clouds in the Sun, each of which were not a tenth part of the bignefsof one of thefe I here have delineated, though very much of the famefliape, which makes me ghefs, that each of thele fwarms might be the of-fpring of one onely Gnat, which had been hoorded up in fome lafe repofitory all this Winter by Ibme provident Parent, and were now, by the warmth of the Spring-air, hatch’d into little Flies.
And indeed, fo various, and leemingly irregular are the generations or produffions of Infeffs, that he that fhall carefully and diligently obferve the (everal methods of Nature therein, will have infinitely caufe further to adraire’the wifdom and providence of the Creator 5 for not onely the fame kind of creature may be produc’d from leveral kinds of ways, but the very fame creature may produce feveral kinds ; For,as divers Watches may be made out of feveral materials, which may yet have all the fame appearance,and move afterthe fame manner,that is,lhew the hour equally true, the one as the other, and out of the fame kind of matter, like WatcheSjHiay be. wrought differing ways, and,as one and the fame Watch
D d niay.
Micrographia.
may, by being diverfly agitated, or mov’d, by this or that agent,'*or after this or that manner, produce a quite contrary effeft : So may it be with thefe moft curious Engines'of Infed’s bodies^ the All-wife God of Nature, may have fo ordered and difpofed the little Automatons^ that when nou- rilhed, aded, or enlivened by this caufe, they produce one kind ofeffed, or animate (hape, when by another they ad quite another way, and ano- ther Animal is produc’d. So may he fo order leveral materials, as to make them,by feveral kinds of methods, produce fimilar Automatons.
But to come to the Defcription of this Infed,as it appears through a Mi~ crofcope^oi which a reprefentation is made in the Scheme. Its head A, is exceeding fmall, in proportion to its body, confiding of two clufters of pearl d eyes B B, on each fide of its head, whole pearls or eye-balls are curioully rang d like thofe of other Flies between thefe,in the forehead of it, there are plac’d upon two fmall blackballs, CC, two long jointed horns, tapering towards the top, much relembling the long horns of Lobfters, each of whofe flems or quills, D D, were brifled or brufiied with multitudes of fmall ftifi' hairs, ifiuing out every way from the feve- ral joints, like the firings orfproutings of the herb which is
oft obferv’d to grow among Corn, and for the whole fhape, it does very much refemble thofe brujhy Vegetables 5 befides thefe, there are two other jointed and brifled horns, or feelers, E E, in the forepart ofthe head, and a probofck* F, underneath,which in feme Gnats are very long, ftreight hollow pipes, by which thefe creatures are able to drill and penetrate the fkin, andjthence, through thofe pipes fuck fb much bloud as to fluff their bellies fo full till they be ready to burfl.
This fmall head,with its appurtenances,is faftned on by a fhort neck,G, to the middle ofthe thorax^ which is large, and feems cafed with a ftrong black fhel,H I K, out of the under part of which, ifliie fix long and flender legs, L L L L L L, fhap’d juft like the legs of Flies, but fpun or drawn out longer and flenderer,which could not be exprefs’d in the Figurc,becaufo of their great length 5 and from the upper part, two oblong, but flender tranfparent wings, M M, fhaped fbmewhat like thofe of a Fly, underneath each of which, as I have obferv’d alfo in divers forts of Flies, and other kinds of Gnats, was placed a fmalP body, N, much refembling a drop of fome tranfparent glutinous fubflance, hardned or cool’d, asit wasal- moft ready to fall, for it has a round knob at the end, which by degrees grows flenderer into a fmall ftem.and neer the infertion under the wing, this flem again grows bigger , thefe little ?endulums^2is I may fo call them, the litle creature vibrates to and fro very quick when it moves its wings, and I have fometimes obferv d it to move them alfo, whil’flthe wing lay flill, but always their motion feem’d to further the motion of the wing ready to follow , of what ufe they are, as to the moving of the wing, or otherwife, I have not now time to examine.
Its belly waslarge,as it is ufually in all Infeds, and extended into nine lengths or partitions, each of which was cover’d with round armed rings or foells ^ fix of which, O P QR S T were tranfparent, and divers kinds of Veri^altkk^ motions might be very eafily perceiv’d, whil’fl the Animal
was
Micrograph! A.
Was alive, but efpecially a fmall deer white part V, feemed to beat like the heart of a larger Animal. The laft three divifios, W X Yj were co- ver’d with black and opacous (hells. To conclude, take this creature altogether, and for beauty and curious contrivances, it may be compared with the largeft Animal upon the Earth. Nor doth the Alwife Creator feem to have (hewn Ids care and providence in the fabrick of it, then in thole which feem mod: confiderable.
Obferv. X L V, Of the great Bellfd Gnat or female Gnat^
THe fccond Gnat , delineated in the twenty ninth Schme^ is of a very differing fhape from the former^but yet of this fort alfo,I found feveral of the Gnats, that were generated out of the Water Inled ; the wings of this, were much larger then thofe of the other, and the belly much bigger, Ihorter and of an other fhape , and, from, feveral particu- lars, I gheft it to be the Female Gnat, and the former to be the Male.
The thorax of this, was much like that of the other,havinga very ftrong and ridged back-piece, which went alfoon either fide of its leggs, about the wings there were leveral joynted pieces of Armor, which feem’d cu- rioully and conveniently contriv’d, for the promoting and flrengthning the motion of the wings.-its head was much differing from the other,being much bigger and neater fhap’d, and the horns that grew out between his eyes on two little balls, were of a very differing fhape from the tufts of the other Gnat, thefe having but a few knots or joynts, and each of thofe but a few, and thofe fhort and ffrong, brifles. The formoft horns or feelers, were like thofe of the former Gnat.
One of thefe Gnats I have fuffer’d to pierce the Ikin of my hand, with its probofeis^ and thence to draw out as much blood as to fill its belly as full as it could hold, making it appear very red and tranlparent, and this without any further pain, then whil ff it was finking in its probofets^ as it is alfb in the hinging of Fleas ; a good argument, that thefe creatures do not wound the fkin, and fuck the blood out of enmity and revenge, but for meet neceffity, and to fatisfy their hunger. By what means this creature is able to fuck, we fhall fhew in another place.,
Obferv. XL VI. Of the ivhite featherwing' d Moth or Tinea Argentea.
THis white long wing’d Moth, Which is delineated in the :^o.Scheme^ afforded a lovely object both to the naked Eye, and through a Mi- crofeope : * to the Eye k appear’d a finall Milk white Fly with four white
D d 2 Wing?
1^6 MiCROGR AP HI A.
Wings 5 the two foriiiofl: fomewhat longer then the two hindermoft, and the two Ihorter about half an Inch long, each of which four Wings (eem'd to confift of two fmall long Feathers, very curioufly tufted, or haired on each fide, with purely white, and exceedingly fine and fmall Haires, pro- portion’d to the ftalks or ftems, out of which they grew, much like the tufts of a long wing-feather of lome Bird, and their ftalks or ftems were, like thofe, bended backwards and downwards, as may be plainly feen by the draughts of them in the Figure.
Obferving one ofthefe in my Microfcope^ found,in the firft place, that all the Body , Legs, Horns and the Stalks of the Wings, were covered over with various kinds of curious white Feathers, which did, with handling or touching, eafily rubb off and fly about, in fo much that looking on my Fingers, with which I had handled this Moth, and perceiving on them lit- tle white fpecks, I found by my Microfeofe^ that they were feveral of the fmall Feathers of this little creature, that ftuck up and down in the ru~ gojities of my Skin.
Next, I found that underneath thefe F eathers, the pretty Inleft was co- vered all over with a crufted Shell, like other of thofe Animals, but with one much thinner and tenderer. |
Thirdly, I found, as in Birds alfb is notable, it had differing and ap- propriate kinds of Feathers, that covered feveral parts of its body. s
Fourthly, furveying the parts of its body, with a more accurate and better Magnifying Microfeope^ I found that the tufts or haires of its Wings were nothing clle but a congeries, or thick fet clufter of fmall vimina. or twiggs, refembling a fmall twigg of Birch, ftript or whitned, with which Brufhes are ufually made, to beat out or brufh off the duft from Cloth and Hangings. Every one of the twiggs or branches that compofed the Brufh of the F eathers, appeared in this bigger Magnifying Clafs (of which E F which repr dents part of an Inch, is the fcale, as G is of the lefler,
which is only 3) like the figure D. The Feathers alfb that covered a « part of his Body, and were interfperfed among the brufh of his Wings, I | fbund,in the bigger Magnifying Glafs, of the fhape A, conflfting of a ftallc |
or ftem in the middle, and a feeming tuftednefs or brufhy part on each \ fide. The Feathers that cover’d moft partof his Body and the ftalkof | his wings, were,in the fame Microfeope^ much of the figure B, appearing of |
the fhape of a fmall Feather, and feemed tufted : thofe which covered |
the Horns and fmall parts of the Leggs, through the fame MicrofcopCj ap- pear’d of the fhape C. Whether the tufts of any or all of thefe fmall Feathers, confifted of fuch component particles as the Feathers of Birds,
I much doubt, becaufe I find that Nature does not alwaies keep, or ope- I rate after the fame method , in fmaller and bigger creatures. And of this, we have particular Inftances in the Wings of feveral creatures.
For whereas, in Birds of all kinds, itcompofes each of the Feathers of which its Wing confifts, of fuch an exceeding curious and moft admirable and ftupendious texture, as I elfe where fhew, in the Obfervations on a Feather 3 we find it to alter its method quite, in the fabrick of the Wings |
of thefe minute creatures, compofing fome of thin extended membranes )
or
Sc hem:
r
VX 1 ^ Iv w Vj Iv A i O i A«
or (kins, ilich as the Wings of Dragon-flys 5 in others, thofe fkins arc all over^grown, or pretty thick beftuck, with fliort brifles, as in Flefh-fiies 5 in others, thofe filmes are covered, both on the upper and under fide, with finall Feathers, plac’d almofr like the tyles on a Houle, and are curioully rang’d and adorn’d with moft lively colours, as is ob- fervable in Butter-flies, and leveral kinds of Moths 5 In others, inftead of their films. Nature has provided nothing, but a matter of half a Icore ftalks(if I well remember the number^ for I have not lately met with any . of thefe flys, and did not, when I firft obferv’d them, take fufficient notice of divers particulars^ and each of thefe ftalks, with a few fingle branch- ings on each fide, refembling much the branched back-bone of a Herring or the like Filh , or a thin hair’d Peacocks feather, the top or the eye being broken off. With a few of thele on either fide( which it was able to Ihut up or expand at plealure, much like a Fann, or rather like the po- fture of the feathers in a wing, which ly all one under another, when (hut, and by the fide of each other, when expanded) this pretty little grey Moth (for fuch was the creature I obferv’d, thus wing’d) could ve- ry nimbly, and as it leem’d very eafily move its corpnfcle , through the Air,from place to place. Other Inleds have their wings cas’d, or cover’d over, with certain hollow Ihdls, lhap’d alraoft like thofe hollow Trayes, in which Butchers carry meat, whole hollow fides being turn’d down- wards, do net only fecure their folded wings from injury of the earth, in which moft of thole creatures refide, but whilft they fly, fervesas a help to luftain and bear them up. And thefe are oblervable in Scarabees and a multitude of other terreftrial cmjiaceouflnk&s 5 in which we may yet further obferve a particular providence of Nature.
Now in all thele kinds of wings, we oblerve this particular, as a thing moft worthy remark 3 that where ever a wing confifts of dilcontinued parts, the Pores or interjiitia between thole parts are very feldom, either much bigger,or much Iraaller, then thele which we here find between the particles of thefe brulhes, fo that it fhould feem to intimate, that the parts of the Air are fuch, that they will not eafily or readily, if at all, pals through thefe Pores, lb that they leem to be ftrainers fine enough to hin- der the particles of the Air (whether hinder’d by their bulk, or by their agitation^ circuUtion^ rotatien or undulation , I ihall not here determine) from getting through them,and,by that means,ferve the Animal as well, if not better, then if they were little films. I lay, if not better, becaufe I have oblerv’d that all thole creatures, that have film’d wings, move them aboundantly quicker and more ftrongly, fuch as all kind of Flies and
and Batts, then fuch as have their wings covered with feathers, as Butter-flies and Birds, ortwiggs, as Moths, which have each of them a much flower motion of their wings 3 That little ruggednels perhaps of their wings helping them lbmewhat,by taking better hold of the parts of the Air, or not luffering them fo eafily to pafs by, any other way then one.
But what ever be therealbn of it, tis moft evident, that the Imooth wing’d Inledts have the ftrongeft Mulbles or movent parts of their wings, and the other much weaker 3 and this very Infeft, we are now delcribing,
had
Micrographia.
had a very {mall thorax or middle part of his body, if compar’d to the length and number of his wings ^ which therefore, as he mov’d them ve- ry flowly,fo muft he move them very weakly. And this laft propriety do we find fomewhat obferv’d alfo in bigger kind of Flying creatures,Birds 5 fo that we (ec that the Wifdom and Providence of the All-wife Creator is not lefs fhewn in thefe fmall defpicable creatures. Flies and Moths, which we have branded with a name of ignominy, calling them Vermine, then in thofe greater and more remakablc animate bodies. Birds.
I cannot here ftand to add any thing about the nature of flying, though, perhaps, on another occafion, I may fay lomething on that fiib* jeft, it being fuch as may delcrve a much more accurate examination and fcrutiny then it has hitherto met with 5 For to me* there feems nothing wanting to make a man able to fly, but what may be eafily enough fup- ply’d from the Mechanicks hitherto known , fave onely the want of ftrength, which theMufcles of a man feem utterly uncapable of, by rea- fon of their Imalnels and texture, but how even ftrength alfb may be me- chanically made, an artificial Mufcle fo contriv d,that thereby a man (hall be able to exert what ftrength he pleafes, and to regulate it alfo to his own mind, I may elfewhere endeavour to manifeft.
Obferv. XL VI I. Of tie Shepherd Spider, or long leggd Spider.
"^He Carter,Shepherd Spider,or long-legg’d Spider,has, for two parti- cularities, very few fimilar creatures that I have met with 5 the firft, which is difcoverable onely by the Microfcope^ and is in the firft and Ic- cond. Figures of the Scheme, plainly deftrib’d, is the curious contri- vance of his eyes, of which (differing from moft other Spiders) he has onely two, and thofe plac’d upon the top of a Imall pillar or hillock,rifing out of the middle of the top of its back, or rather the crown of its head, for they were fix’d on the very top of this pillar (which is about the heighth of one of the traniverfe Diameters of the eye, and look’d on in another pofture,appear‘d much of the fliape, BCD) The two eyes,* B B, were placedback to back, with the tranfparent parts,or the pupils, look- ing towards either fide, but fomewhat more forward then backwards. C was the column or neck on which they ftood, and D the crown of the head out of which that neck fprung.
Thefe eyes,to appearance, feem’d to be of the very lame ftrudure with that of larger binocular creatures, feeming to have a very fmooth and ve- ry protuberant Cornea^zad in the midft of it to have a very black pupil, incompalfed about with a kind of grey Iris, as appears by the Figure 5 whether it were able to move thefe eyes to and fro, I have not obferv’d, but ’tis not very likely he fhould,the pillar or neck C, feeming to be co- ver’d and ftiflfen’d with a crufty ftiell 5 but Nature, in probability, has (up-
Micrograph i a.
ply’d that defect, by making the Cornea fo very protuberant, and letting it fo deer above the fhadowing or obftruding of its profpedc by the bodyj that’tis likely each eye may perceive,though not fee diftindtly, almoft a Hemijpkere^ whence having fo fmall and round a body plac’d upon fuch long leggs, it is quickly able fo to wind, and turn it, as to fee any thing diftind. This creature, as do all other Spiders I have yet examin’d, does very much differ from mod: other Infeds in the Figure of its eyes ^ for I cannot, with miy bed Microfeope^ difeover its eyes to be any ways knobb’d or pearl’d like thofe of other Infeds.
The fecond Peculiarity which is obvious to the eye, is alfo very re- markable, and that is the prodigious length of its leggs, in proportion to its fmall round body, eachlegg of this I drew, being above fixteen times the length of its whole body, and there are fome which have them yet longer, and others that feem of the fame kind,that have them a great deal fhorter^ the eight leggs are each of them jointed, juft like thofe of a Crab, but every of the parts are fpiui out prodigioully dPPger in pro- portion^ eachofthefe leggs are terminated in'a fmall cafeorfhell,lhap’d almoft like that of a Mulle-fhell, as is evident in the third Figupeo^ the idiTiXQScheme (that reprefents the appearance of the under part or belly of the creature) by the fhapeof the protuberant conical body, 1 1 1 1, Thefo are as ’twere plac’d or faften’d on to the protuberant body of the Infed,which is to be fuppos’d very high at M, making a kind of blunt cone whereof M is to be foppos’d the Apex, about which greater cone of the body,the fmaller cones of the leggs are plac’d,each of them almoft reach- ing to the top info admirable a manner, as does not a little manifeftthe wifdom of Nature in the contrivance , for thefe long Leavers (as I may fo call them)of the legs,havingnot the advantage of a long end on the other fide of the hypomochlion or centers on which the parts of the leggs move, muft neceflarily require a vaft ftrength to move them , and keep the body ballanc’d and lufpended, in fo much, that if we ftiould fuppofo a man’s body fufpended by fuch a contrivance, an hundred and fifty times the ftrength of a man would not keep the body from falling on the breaft. To fupply therefore each of thefo leggs with its proper ftrength. Nature has allow’d to each a large Cheft or Cell, in which is included a very large and ftrong Mufcle, and thereby this little Animal is not onely able to iulpend its body upon left then thefo eight, but to move it very fwiftly over the tops of graft and leaves.
Nor are thefo eight leggs fo prodigioully long, but the ninth, and tenth, which are the two claws, K K, areas Ihort, and ferye infteedofa prohjeis^ for thofe foem’d very little longer then his mouth, each of theln had three parts , but very Ihort , the joints K K, which reprefonted the third, being longer then both the other. This creature, foems (which I have feveral times with pleafure obforv’d) to throw its body upon the prey, infteed of its hands, not unlike a hunting Spider, which leaps like a Cat at aMoufo. The whole Fabrick was a very pretty one, and could I have dilfofted it,I doubt not but I fhould have found as ma- ny fingularities within it as without, perhaps, for the moft part,not unlike
the
200
Ml CROGRAHP I A.
the parts of a Crab, which this little creature' does in many things, very much refemble^ the curiofityof whole contrivance,! have in another place examin’d. I omit the defeription of the horns, A A, of the mouth, L L, which feem’d like that of a Crab ^ the fpecklednefs of his (hell, which proceeded from a kind of feathers or hairs, and the hairinels of hisleggs, his large thorax and little belly, and the like, they being manifelfed by the Figure 5 and (hall oncly take notice that the three parts of the body, namely, the head,breaft,and belly,are in this creature ft rangely confus d, fo that ’tis difficult to determine which is which,as they are alfo in a Crab 5 and indeed, this leemsto be nothing elfe, but an Air^crab, being made more light and nimble, proportionable to the medium wherm itrefides ^ and as Air feems to have but one thoulandth part of the body of Water,lb does this Spider feem not to be a thoufandth part of the bulk of a Crab.
Obferv. X L V 1 1 1. Of the hunting Spider, fever al other forts cf Spiders.
'^He hunting Spider is a fmall grey Spider, prettily btfpeck’d with black Ipots all over its body, which the Microjeope dilcovers to be a kind of feathers like thofe on Butterflies wings, or the body of the white Moth I lately delcrib’d. Its gate is very nimble by fits, Ibmetimes running, and fometimes leaping, like a Grafhopper almoft,then ftandidg (fill, and fetting it (elf on its hinder leggs, it will very nimbly turn its body, and look round it felf every way ; It has fix very confpicuous eyes, two looking diredfly forwards, plac’d juft before , two other, on either fide of thole, looking forward and fide-ways,and two other about the middle of the top of its back or head, which look backwards and fide- wards 5 thele feem’d to be the biggeft. The furface of them all was very black,fphaerical, purely polilh’d, refleding a very deer and diftinft Image of all the ambient objeds, fuch as a window,a man’s hand,a white Paper, or the like. Some other properties of this Spider, obferv’d by the moft accumplilh’d Mr. Evelyn^ in his travels in Italy^ are moft empha- tically fet forth in the Hiftory hereunto annexed, which he was pleas’d upon my defire to fend me in writing.
Of all the forts of Infefls, there is none has afforded me more divertifements then the Venatores^ which arc a fort of Lufi^ that have their Denns in the rugged walls, and crevices of our houfes ; a fmall brown and delicately fpotted kind of Spiders, whofe hinder leggs are longer then the reft.
Such I did frequently obferve at Bome^ which efpying a Fly at three or four yards diftancc,upon the Balcony (where I ftood)
would
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M I C R O G R A P H 1 A.
would not make diredly to her, but craul under the Rail, till being arr iv’d to the Antipodes^ it would Real up, feldom miffing its aim ; but if it chanced to want any thing of being perfedly oppolite,would at firft peep, immediatly Aide down again, till taking better notice, it would come the next time exactly upon the Fly’s back : But, if this hapn’d not to be within a compe- tent leap, then would this InfeR move fo foftly, as the very fhadow of the Gnomon feem’d not to be more imperceptible, unlels the Fly mov’d ; and then would the Spider move alfo in the fame proportion, keeping that juft time with her motion,as if the fame Soul had animated both thole little bodies ; and whether it were forwards, backwards, or to either fide, without at all turning her body, like a well mannag’d Horfe : But, if the capricious Fly took wing, and pitch’d upon another place behind our Huntrefs, then would the Spider whirle its body fo nimbly about, as nothing could be imagin'd more fwife ; by which means,(he always kept the head towards her prey,though to appearance, as immovable, as if it had been a Nail driven into the Wood, till by that indifcernable progrefs (being ar- rived within the fphere of her reach) Ihemadea fatal leap (fwift as Lightning) upon the Fly, catching him in the pole, where (he never quitted hold till her belly was full^ and then carried the remainder home. I have beheld them inftrufting their young ones, how to hunt, which they would fometimes difcipline for not well oblerving ; but, when any of the old ones did (as fometimes) mils a leap, they would run out of the field, and hide them in their crannies, as alham’d, and haply not be feen abroad for four or five hemrs after ; for fo ; long have I watched the nature of this ftrange Infed, the con- templation of whofe fo wonderfulf fagacity and addrefs has amaz’d me ; nor do I find in any chafe whatfoever, more cun- ning and Stratagem oblerv’d 1 1 have found fome of thele Spi- ders in my Garden, when the weather (towards the Spring)
' E e is
202
Micrographia.
is very hot, but diey arc nothing fo eager of hunting as they arc in Italy*
There are multitudes of other forts of Spiders, whofe eyes, and moft other parts and properties, are fo exceedingly different both from thofe I have delcrib'd, and from one another, that it would be almoft endlefs, at leaft too long for my prefent Eflay, to delcribe them,as fbme with fix eyes, plac’d in quite another order 5 others with eight eyes j others with fewer, and Ibme with more. They all (eem to be creatures of prey, and to feed on other fmall Infefts, but their ways of catching them feem very differing : the Shepherd Spider by running on his prey , the Hunting Spi- der by leaping on it,other forts weave Nets, or Cobwebs, whereby they cnlhare them. Nature having both fitted them with materials and tools, and taught them how to work and weave their Nets, and to lie per- due, and to watch diligently to run on any Fly, as foon as ever en- tangled.
Their thread or web feems to be fpun out of Ibme vifeous kind of excrement, lying in their belly, which, though foft when drawn out, is, prefently by reafbn of its fmalnefs, hardned and dried by the ambient Air. Examining feveral of which with my Mkrofiopey found them to lap- pear much like white Horf-hair, or fbme fuch tranfparent horny fubftance, and to be of very differing magnitudes ^ fome appearing as bigg as a Pigg’s brifle, others equal to a Horfs-hair , other no bigger then a man’s hairs others yet fmaller and finer. I obferv’d further, that the radia- ting chords of the web were much bigger, and fmoother thenthofe that were woven round, which feem’d fmaller, and all over knotted or pearl’d, with fmall tranfparent Globules, not unlike fmall Cryftal Beads or feed Pearls, thin ftrung on a Clew of Silk 5 which, whether they were fb fpun by the Spider, or by the adventitious moifture of a fogg (which I have obferv’d to cover all thefe filaments with fuch Cryftalline Beads) I will not now difpute.
Thefe threads were fome of them fo fmall, that I could very plainly, with the Microfeope^ difeover the fame confecutions of colours as in a Trifme^ and they feem’d to proceed from the fame caufe with thofe co- lours which I have already deferib’d in thin plated bodies. . ,
Much referabling a Cobweb, or a confus’d lock of thefe Cylih- ders, is a certain white fubftance which, after a fogg, may be bbfery’d to fly up and down .the Air 5 catching feveral of thefe, and examining them with my Microfeope^ I found them to be much of the lame f6rm, looking moft like to a flake of Worfted prepar’d to be fpun, . dhough by what means they fhould be generated, or produc’d, is npt eafily imagined; they were ofthe fame weight, or very little heavier then the Air 5 and ’tis not unlikely, but that thofe great white clouds, that appear all the Summer time, maybe of the fame mbftance. ...
Obferv.
Micrograph! A.
203
Obferv. XLIX. Of an Ant or
THis was a creaturCj more troublelbm to be drawn, then any of the reft, for I could not, for a good while, think of a way to make it ftiffer its body to ly quiet in a natural pofture 5 but whifft it was alive, if its feet were fetter d in Wax or Glew , it would fo twift and wind its body, that I could not any wayes get a good view of it 5 and if I killed it, its body was fo little, that I did often ipoile the fhape of it, before I could throughly view it ; for this is the nature of thefe minute Bodies , that as foon,almoft, as ever their life isdeftroy’d, their parts immediate- ly fhrivel, and lofe their beauty 5 and fo is it alfb with final! Plants, as I inftanced before, in the defeription of Mofs. And thence allb is the rea- Ibn of the variations in the beards of wild Oats, and in thofe of Mulk- grals feed, that their bodies, being exceeding fmall, thofe fmall variations which are made in the furfaces of all bodies, almoft upon every change of Air, efpecially if the body be porous, do here become fenfible, where the whole body is fb fmall, that it is almoft nothing but furface 3 for as in vegetable fubftances, I fee no great reafbn to think, that the moifture of the Aire(ihat, fticking to a wreath’d beard, does make it untwift Jfhould. evaporate, or exhale away, any fafter then the moifture of other bodies, but rather that the avolation from, or accefs of moifture to, the furfaces of bodies being much the fam e , thofe bodies become moft fenfible of it, which have the leaft proportion of body to their furface. So is it alfb with Animal fiibftances , the dead body of an Ant, or fuch little creature, does almoft inftantly fhrivel and dry, and your objed fhall be quite an- other thing, before you can half delineate it, which proceeds not from the extraordinary exhalation, but from the fmall proportion of body and jui- ces, to theufual drying of bodies in the Air, efpecially if warm. For which inconvenience, where I could not otherwife remove it, I thought of this expedient.
I took the creature, I had defign’d to delineate, and put it into a drop of very well redified fpirit of Wine,this I found would prefently difpatch, as it Were, the Animal, and being taken out of it, and lay’d on a paper, the fpirit of Wine would immediately fly away, and leave the Animal dry, in its natural pofture, or at leaft, in a conftitution, that it might eafi- ly with a pin be plac’d, in what pofture you defired to draw it, and the limbs would fb remain, without either moving, or fhriveling. And thus I dealt with this Ant, which I have here delineated, which was one of ma- ny, of a very large kind, that inhabited under the Roots of a Tree, from whence they would fally out in great parties, and make moft grievous havock of the Flowers and Fruits, in the ambient Garden, and return back again very expertly, by the fame wayes and paths they went.
It was more then half thebignefsof an Earwig, of a dark brown, or reddifh colour, with long legs, on the hinder of which it would ftand
E e 2 up.
Micrographia.
upjSnd raife its head as high as it could above the ground, that it might Itare the further about it, juft after the fame manner as I have alfo oh- lerv'd a hunting Spider to do : and putting my finger towards them, they have at firft all run towards it,till almoft at it ^ and then they would ftand round about it, at a certain diftance, and fmell, as it were, and con- fidcr whether they ftiould any of them venture any further, till one more bold then the reft venturing to climb it, all the reft, if I would have fufter- ed them, would have immediately followed : many fuch other leeming- ly rational adions I have obferv’d in this little Vermine with much plea- fiire,which would be too long to be here related 3 thofe that defire more of them may fatisfie their curiofity in Ligens Hiftory of the Barkicloes.
Having infnaf d fcveral of thefe into a fmall Box, I made choice of the talleft grown among them, and feparating it from the reft,I gave it a Gill of Brandy, or Spirit of Wine, which after a while e en knock’d him down dead drunk, fo that he became moveleft, though at firft putting in he ftruggled fora pretty while very much, till at 1 aft, certain bubbles iftu” ing out of its mouth, it ceafed to move 5 this ( becaufe I had before found them quickly to recover again, if they were taken out prefently ) I fufiered to lye above an hour in the Spirit , and after I had taken it out, and put its body and legs into a natural pofture, remained move* left about an hour 5 but then , upon a fudden, as if it had been awa- ken out of a drunken fleep, it fuddenly reviv’d and ran away 5 be* ing caught, and lerv’d as before, he for a while continued ftruggling and ftriving,till at laft there iflued feveral bubbles out of its mouth, and then, tanquam animam expirajjet^ he remained movelefs for a good while 3 but at length again recovering, it was again redipt, and liilfered to lye Ibme hours in the Spirit 5 notwithftanding which , after it had layen dry (bme three or four hours, it again recovered life and motion : Which kind of Experiments, if prolecuted, which they highly deferve, leem to me of no inconfiderable ufe towards the invention of the Latent Scheme^ (as the Noble VeruUm calls it) or the hidden, unknown Texture of Bodies.
Of what Figure this Creature appear’d through the Microjeope, the 32. Scheme ( though not lb carefully graven as it ought ) will repre- lent to the eye, namely. That it had a large head A A, at the upper end of which were two protuberant eyes, pearl’d like thofe of a Fly, but fmaller B B 3 out of the Nofc,or fbremoft part, iflued two horns C C, of a lhape liifficiently diftering from thole of a blew Fly, though indeed they leem to be both the lame kind of Organ, and to lerve for a kind of Iraelling 3 beyond thefe were two indented jawsDD, which he o- pen’d lide-wayes, and was able to gape them afunder very wide ^ and the ends of them being armed with teeth, which meeting went between each other, it was able to gralp and hold a heavy body , three or four times the bulk and weight of its own body : It had only fix legs, lhap’d like thole of a Fly, which, as I Ihewed before, is an Argument that it is a winged Infedt, knd though I could not perceive any lign of them in the midiepartof its body ( which feem’dto confift of three joints or pie-
I '
■i, ■ ,• .
' • ' A '
■ > ' ■ .■ . ■ ■ /'
i.'
I CROGR APHl Ai
ces EF G, out of which fprung two legs, yet ’tis known that there are of them that have long wings, and fly up and down in the air.
The third and laft part of its body III was bigger and larger then the other two 3 unto which it was joyn’d by a very fmall middle , and had a kind of loofelhell^ or another diftindt part of its bodyH, which feem’dto be interposdj and to keep the thorax belly from touch° ing.
The whole body was cas d over with a very ftrong armour, and the belly III Was covered likewife with multitudes of (mall white fhining brifles ^ the legs, horns, head, and middle parts of its body were beftucfe with hairs alfo, butfmaller and darker.
Oblcrv. L, the voandring Mite.
IN Septeptbeir ziyAO&ober^ i66i. I obferv’d in Oj^or^/frveralof thele J little pretty Creatures to wander to and fro,and often to travel over the plains of my Window. And in Septepiber m^oBober. i56g. I ob- lerv’d likewife leveral of thefe very fame Creatures traverfing a window ztLondofjy and looking without the window upon the fubjacent Wall, I found whole flocks of the fame kind running to and fro among the fmall groves and thickets of green mofs, and upon the curioufly fpreading ve-^ getable blew or yellow mofs , which is a kind of a Mufhrome or Jews-^ car.
Thefe Creatures to the naked eye feemed to be a kind of black Mite, but much nimbler and ftronger then the ordinary Cheefe-Mites ^ but examining them in a Microfeope^ I found them to be a very finecruffed or fhelfd Infedr, much like that reprefented in the firft Figure of the three and thirtieth Scheme^ with a protuberant oval fhell A, indented or pitted vvith an abundance of fmall pits 5 all covered over with little white brifies, whofe points all direfted backwards.
It had eight legs, each of them provided with a very fharp tallon, or elawat the end, which this little Animal, in its going, faftned into the pores of the body over which it went. Each of thefe legs were beftuck in every joynt of them with multitudes of fmall hairs, or ( if we re- fped the proportion they bore to the bignefs of the leg ) turnpikes, all pointing towards the claws.
The T^<?r4x,or middle parts of the body of this Creature, was exceed-’ ing fmall, in refped both of the head and belly , it being nothing but that part which was covered by the two fhells BB, though it feem'd to grow thicker underneath: And indeed, if we confider the great variety Nature ufes in proportioning the three parts of the body, the Thorax^ and Bel/y ) we fhall not wonder at the fmall pro- portion of this "ikorax, nor at the vafter bulk of the belly, for could we exadly anatomife this little Creature, and obferve the particular de- frgns of each part, we fliould doubtlefsj as we do in ail her more ma- nageable
2o6
Micrographia. I
nageable and traftable fabricks , find much more reafon to admire the ^
excellency of her contrivance and workmanlhip, then to wonder^ it was '
not made otherwile. I j
The head of this little In(e6l was fliap’d Ibmewhat like a Mite’s, that |
is,it had a long fnout , in the manner of a Hogs, with a knobbed ridge |
running along the middle of it, which was beftuck on either fide with I*
many fmall brides, all pointing forward, and two very large pikes or horns, which rofe from the top of the head, juft over each eye, and ;
pointed forward alfb. It had two pretty large b lack eyes on either fide of the head E E, from one of which I could fee a very bright refledion |
of the window, which made me ghefs, that the Cornea of it was fmooth, like thofe of bigger Infeds. Its motion was pretty quick and ftrong, it being able very eafily to tumble a ftone or clod four times as big as its whole body.
At ilie lame time and place, and divers times fince, I have oblerved !
with my Microfeope , another little Infed , which, though I have not an- nexed the pidure of, may be worth noting, for its exceeding nimblenels as well as fmalneft, it was as Imall as a Mite, with a body deep and ridged, almoft like a Flea 5 it had eight blood-red legs, not very long, but flender 5 and two horns or feelers before. Its motion was fo excced- ing quick, that I have often loft fight of one I have oblerved with my naked eye 5 and though, when it was not frighted, I wis able to follow the motions of fome with my Aljcrofcope , yet if it were never fo little i ftartled, it pofted away with foch fpecd, and turn’d and winded it folf fo quick, that I Ihould prefently lofe fight of it. I
When I firft obforv’d the former of thele Infeds, or Mites, I began to conjedure, that certainly I had found out the vagabond Parents of thofo j Mites we find in Cheeles, Meal, Corn, Seeds, mufty Barrels, mufty Lea- '
ther, thefo little Creatures, wandring to and fro every whither, !
might perhaps, as they were invited hither and thither by the mufty fteamsof foveral putrifying bodies, make their invafions upon thofo new and pleafing territories , and there {pending the remainder of their life, which might be perhaps a day, or thereabouts, in very plentiful and rio- tous living , might leave their off-lpring behind them , which by the change ol the foil and Country they now inhabite, might be quite al- ter’d from the hew of their primogenitors^ and, like Mores tranflated into Northern European Climates, after a little time, change both their skin andfhape. And this foems yet more probable in thefo Infods , becaufe that the foil or body they inhabit, foems to be almoft half their parent, f for it not only hatches and brings thofo little eggs, or feminal principles, to perfedion, but foems to augment and nourifh them alfo before they are hatch’d or fliaped 5 for it is obvious enough to be obforv’d, that the | eggs of many other Infods, and particularly of Mites, are increas’d in bulk after they are laid out of the bodies of the Infods, and plump’d fometimes into many time^their former bignels , fo that the bodies they are laid in being, as it were, half their mothers, we (hall not wonder that it ftiould have fuch an adive power to change their forms. We find by
relations.
MiCROGRAPHlA.
telations how much the Negro Women do befmeef the of-fpi-ing of the Spaniard^ bringing forth neither white-fkinn’d nor black, but tawn.y hided Mulattos.
Now, though I propound this as probable, I have not yet been (b farr tertify’d by Obfervations as to conclude any thing, either pafitively ot negatively jconcerning it. Perhaps, feme more lucky diligence may pleafo the curious Inquirer with the dilcovery of this, to be a truthjwhich'l now conjecture, and may thereby give him a latisfaCtory account of the caufe of thofe creatures,whofe original feems yet fo obfcure, and may give hint caulc to bclieve,that many other animate beings, that foem alfd to be the mere product of putrifaCtion, may be innobled with a Pedigree as anci- ent as the firft creation, and farr exceed the greateftbeingsititheir nu- merous Genealogies. But on the other fide, ifSt Ihould be found that thefojOr any other animate body, have no immediate fimilar Parent,! have in another place let down a conjeCtural H^pothejis whereby thole Vha-- nomena may likely enough be folv’d, wherein the infinite wildom and providence of the Creator is no lefs rare and wonderful!.
Obferv* LI, Of the Grab4ike hfe^i
R Fading one day in Septemh. I chanced tooblerve a very final creature creep over the Bock I was reading,very flowly 5 having a Microfeepe by me,I obferv’d it to be a creature of a very unufual form, and that not lefs notable 5 luch as is delcrib'd in the fecond Figure of the. 33. €cheme. It was about the bignhfs of a lar^'Mtte^orfomewhat longer^it hadteolegs, eight of which, AAAA^ were topt with verylharp claws, and were thole •upOB which he walk’d, leeming lhap’d much like thofeof a Crab, which in many other things alfo this little creature refembled 5 for the tv/o other claws,B B, which were the formoftof all the ten, and feem’d to grow out of his head,like the horns of other Animals,Were exaCHy fdtm’d in the manner of Crabs or Lobfters claws, for they were fbap’d and jointed much like thole reprefened in the the ends of thenii werefiir-
nilh’d with a pair of claws or pincers, C C, which this little animal did opte® and fhut at pleafure ; It leem’d to make ule of thole two horns Or daws both for feelers and holders 5 for in its motion it carried thefe aloft ex== tended before, moving them to and fro, juft as a man blindfolded would do his hands when he is fearfull of running againft a wallL, ^ and if t put a hair to it, it would readily take hold of it with thefe- diawsi) -and feem to hold it faft. Now, though thefe horns leem’d to ferve him for two ufes, namely ,for feeling and holding 5 yet he leem’d neither blind, having two Imall black fpots, D D, which by the make of them, and the bright refledion If om them feem’d to be his eyes 5 nor did it want other hands, having another pair of claws, E E, very neer plac’d to its mouth, and feem’d adjoining to it.
The whole body was cafed over with arm'our-.ftiells, as k tifoall in all
thofe
Micrograhp iV.
thofe kinds of cmjiaceous creatures, efpecially about their bellies, and feem’d of three kinds 5 the head F feem’d cover’d with a kind of fcaly fhell, the thorax with two fmooth (hells, or Rings, G G, and the belly with eight knobb’d ones. I could not certainly find whether it had under thele laft (hells any wings, but I fufped: the contrary , for I have not found any wing’d Infeft with eight leggs, two of thofe leggs being always con- verted into wings, and, for the moft part, thole that have but (ix, have wings.
This creature, though I could never meet with more then one of them, and fo could not make (b many examination^ of it as otherwife I ’ would, Idid notwithftanding,by reafon of the great curiofity that appear’d to me in its (hapejdclineate it, to (hew that,in all likelihood. Nature had crouded together into this very minute Infed, as many, and as excellent contrivances, as into the body of a very large Crab, which exceeds it in bulk,perhaps,(bme Millions of times 5 for as to all the apparent parts, there is a greater rather' then a le(s multiplicity of parts,each legg has as many parts, and as many joints as a Crabs, nay,and as many hairs or brides 5 and the like may be in all the other vifible parts 5 and ’tis very likely,thatthe internal curiofities are not le(s excellent : It being a general rule in Na- ture’s proceedings, that where (he begins to difplay any excellency, if thefubjedl: be further fearch’d into, it will raanifed, that there is not le(s curiolity in thofe parts which our (ingle eye cannot reach, then in tho(e which are more obvious.
Obferv. L 1 1. Of the [mall Silver-colour d Book-worm.
As among greater Animals there are many that are (baled, both for ornament and defence, (b are there not wanting fuch al(b among the leffer bodies of Infefts^ whereof this little creature gives us an Inftance. It is a fraali white Silver-(hining Worm or Moth, which I found much con- verlant among Books and Papers, and is fuppos’d to be that which cor- rodes and eats holes through the leaves and covers^ it appears to the naked eye, afmall gliftering Pearl-colour’d Moth, which upon the remov- ing of Books and Papers in the Summer, is often obferv’d very nimblyrto feud, and pack away to (bme lurking cranney, where it may the better proteft it (elf from any appearing dangers. Its head appears bigg and blunt, and its body tapers from it towads the tail, (mailer and fmaller,be- ing (hap’d almoft like a Carret. ^
This the yI//Vr£/c<?p7c<i/appearance will more plainly manifeftjWhichex^ hibits,inthe third of the Scheme^ a conical body, divided info
fourteen feveral partitions, being the appearance of (b many (everal (hels, or (hields that cover the whole body, every of the(e (hells are again co- ver’d or tiled over with a multitude of thin tranlparent (bales, which, from the multiplicity of their reflebiing (urfaces,raake the whole Animal appear of a perfebtPearl-colour.
Which
Micrographia* 205
Whichjby the wayjinay hint us the reafon of that fo much admired ap- pearance of thofefo highly efteem'd bodies, as alfo of the like in mother of Pearl-ftiells, and in multitudes of other fhelly Sea-fubftances 5 for they each of them confifting of an infinite number of very thin fhells or la- minated orbiculations, caufe fuch multitudes of refleftions, that the com- pofitions of them together with the refleftions of others that are fo thin as to afford colours (of which I elfewhere give the reafon) gives a ve- ry plealant reflexion of light. And that this is the true caufojfeems likely, firft, becaufe all thofe fo appearing bodies are compounded of multitudes of plated fubftanccs. And next that, by ordering any trafparent fobftance after this manner, the like rhanomena may be produc’d , this will be made very obvious by the blowing of Glafs into exceeding thin Ihells, and then breaking them into fcales,which any lamp-worker will prelently do 5 for a goodquantity of thefe fcales,laid in a heap together,have much the iame refomblance of Pearls. Another way, not lefs inftruftive and plea- fant, is a way which I have feveral times done, which is by working and toffing,as ’twere, a parcel of pure cry ftalline glals whilft it is kept glowing hot in the blown flame of a Lamp, for,by that means, that purely tranfpa- rent body will be lb divided into an infinite number of plates, or fmall firings, with interpos’d aerial plates and fibres^ that from the multiplicity of the reflexions from each of thofe internal furfaces, it may be drawn out into curious Pearl-like or Silver wire, which though fmall, will yet be opacous'^ the fame thing I have done with a compofition of red Colo- phon and Tnrpentinc^ and a little Bees Wax, and maybe donelikewifo with Birdlime, and fuch like glutinous and tranfparent bodies ; But tore- turn to our defoription.
The fmall blunt head of this InfeX was furnifh’d on either fide of it with a duller of eyes, each of which feem’d to contain but a very few, in comparifon of what I had obforv’d the duffers of other InfeXs to abound with 5 each of thefo cluflers were befet with a row of fmall brifles, much like the cilia or hairs on the eye-lids, and, perhaps, they ferv’d for the fame purpofe. It had two long horns before, which were flreight, and tapering towards the top, curioufly ring d or knobb’d, and brifled much like theMarfh \yeed, call’d Horfe-tail,or Cats-tail, having at each knot a fring’d Cirdlc,as I may fo call it, of fmaller hairs, and feveral bigger and larger brjfles,here and there difpers’d among them : befides thefo, it had two fhorter horns, or feelers, which were knotted and fring’d, juft as the former, but wanted brifles, and were blunt at the ends 5 the hinder part ofthecreature was terminated with three tails, in every particular re- fembling the two longer horns that grew out of the head : The leggs of it were foal’d and hair’d much like the reft, biit are notexprefs’d in this Figure^ the Moth being intangled all in Glew, and fo the leggs of this appear’d not through the Glafs which looked perpendicularly upon the back.
This Animal probably feeds upon the Paper and covers of Books, and perforates in them foveral fmall round holes, finding, perhaps, a conve- nient nourifljment in thofe hufks of Hemp and Flax, which have pafs’d
F f through
210
Micrographia.
through fo many fcouringSj wafhings,dreir5ngs and dryings,’’ as the parts of old Paper muft neceflarily have fuffer’d:, the digeftiye facultyjit Teems, ofthele little creatures being able yet further to work uponthoTe ftub- born parts, and reduce them into another form.
And indeed, when I confider what a heap of Saw-duft or chips this little creature (which is one of the teeth of Time) conveys into its in- trals. I cannot chufe but remember and admire the excellent contrivance of Nature, in placing in Animals fuch a fire, as is continually nourifhed and fupply’d by the materials convey’d into the ftomach, zu^ fomented by the bellows of the lungs 5 and in fo contriving the moft admirable fabrick of Animals, as to make the very Ipending and wafting of that fire, to be inftrumental to the procuring and collefting more materials to augment and cherilh it felf, which indeed feems to be the principal end of all the contrivances obfervable in bruit Animals.
Obferv. LI 1 1. 6?/^ Flea.
*^He ftrength and beauty of this fmall creature, had it no other rela- tion at all to man,, would deferve a defeription.
For itsftrength, the Microfeope is able to make no greater difeoveries of it then the naked eye, but onely the curious contrivance of itsleggs and joints, for the exerting that ftrength,is very plainly manifefted, fuch as no other creature, I have yet obferv’d, has any thing like it 5 for the joints of it are fo adapted,that he can,as ’twerc,fold them fhortonc with- in another, and fiiddenly ftretch,or fpring them out to their whole length, that is, of the fore-leggs, the part A, of the 34. Scheme^ lies within B, and B within C, parallel to, or fide by fide each other , but the parts of the two next, lie quite contrary, that is, D without E, and E with- out F, but parallel alfo 5 but the parts of the hinder leggs, G, H and I, bend one within another, like the parts of a double jointed Ruler, or like the foot, legg and thigh of a man 5 thefe fix leggs he ditches up al- together, and when he leaps, Iprings them all out, and thereby exerts his whole ftrength at once.
But, as for the beauty of it, the Microfeope manifefts it to be all over adorn’d with a curioully polifh’d fuit of fable Armour, neatly jointed, and befot with multitudes of (harp pinns, fhap’d almoft like Porcupine’s Quills, or bright conical Steel-bodkins 3 the head is on either fide beau- tify’d with a quick and round black eye K, behind each of which alfo appears a (mall cavity, L, in which he feems to move to and fro a cer- tain thin film belet with many fmall tranfparent hairs, which probably may be his cars 5 in the forepart of his head, between the two forc-leggs, he has two fmall long jointed feelers, or rather fmellers, M M, which have four joints,and are hairy, like thole of (everal other creatures , between the(e,it has a (mall probojek^ox probe^ NNO, that feems to confift of a
tube,
2,iO
2II
Micrographia.
tube N N, and a tongue or fucker Oj which I have perceiv’d him to flip in and out. Befides thefe, it has alfo two chaps or biters P P, which are fomewhat like thofe of an Ant , but I could not perceive them tooth’d 3 thefe were lhap’d very like the blades of a pair of round top’d Scizers, and were opened and Ihut juft after the fame manner 5 with thefe Inftru^ ments does this little bufie Creature bite and pierce the fkin^ and fuck out the blood of an Animaldeavingthe fkin inflamed with a fmall round red fpot. Thefe parts are very difficult to be difeovered, becaufe, for the moft part, they lye covered between the fore-legs. 1 here arc many other particulars, which, being more obvious, and affording no great matter of information , I Ihall pals by , and refer the Reader to the Fi- gure.
Obferv. LlV. Of a Loufe,
THis is a Creature fo officious , that ’twill be knowm to every one at one time or other, fo bufie, and fb impudent, that it will be intru- ding it felf in every ones company, and fo proud and afpiring withall, that it fears not to trample on the beft, and affeds nothing fb much as a Crown 5 feeds and lives very high, and that makes it fo fancy, as to pull any one by the ears that comes in its way, and will never be quiet till it has drawn blood ; it is troubled at nothing fo much as at a man that fcratchcs his head, as knowing that man is plotting and contriving fbmc mifehief againftit, and that makes it oftentime fculk into fome meaner and lower place, and run behind a mans back, though it go very much againft the hair 3 which ill conditions of it having made it better known then trufted, would exempt me from making any further defeription of it, did not my faithful Mercury^ my Aficrofeope^ bring me other infor- mation of it. For this has difeovered tome, by means of a very bright light call: on it, that it is a Creature of a very odd fhape 3 it has a head lhap’d like that expreft in Scheme marked with A, which feems al- moft Conical, but is a little flatted on the upper and under fidcs, at the biggeft part of which, on either fide behind the head ( as it were, be- ing the place where other Creatures ears ftand) are placed its two black fhining goggle eyes BB, looking backwards, and fenced round with fe- veral fmall cilia or hairs that incompafs it,fo that it feems this Creature has no very good forefight : It does not feem to have any eye-lids , and therefore perhaps its eyes were fo placed, that it might the better cleanfe them with its fore-legs 3 and perhaps this may be the reafon, why they fo much avoid and run from the light behind them , for being made to live in the fhady and dark recedes of the hair, and thence probably their eye having a great aperture, the open and clear light, efpecially that of the Sun, muft needs very much offend them 3 to fecure thefe eyes from receiving ajiy injury from the hairs through which it pafl'es , it has
F f 2 two
212
Micrograph! A.
two horns that grow before it, in the place where one would have thought the eyes Ihould be , each of thele C C hath four joynts, which are fringed, as ’twere, with fmall brides, from which to the tip of its fnout D, the head feems very round and tapering, ending in a very fharp no(e D, which feems to have a fmall hole, and to be thepaflage through which he fucks the blood. Now whereas if it be plac'd on its back, with its belly upwards, as it is in the 5 5. Scheme^ it feems in feve- ral Pofitions to have a refemblance of chaps, or jaws, as is reprelented in the Figure by E E, yet in other poftures thofe dark ftrokes difappear 5 and having kept feveral of them in a box for two or three dayes, fo that for all that time they had nothing to feed on, I found, upon letting one creep on my hand, that it immediately fell to fucking, and did neither feem to thrufl: its nofe very deep into the fkin, nor to open any kind of mouth, but I could plainly perceive a fmall current of bloodj which came direftly from its fnout, and pad into its belly 5 and about A there feem’cfa contrivance, fomewhat refembling a Pump, pair of Bellows, or ♦ Heart, for by a very fwift jjfiole and diajiok the blood feem'd drawn from the nofe, and forced into the body. It did not feera at all,though I viewed it a good while as it was fucking, to thruft more of its nofe in- to the fkin then the very fnout D, nor did it caufe the leaff difcernable pain, and yet the blood feem’d to run through its head very quick and freely, fb that it feems there is no part of the fkin but the blood isdi- fpers’d into, nay, even into the cutknla ^ for had it thruft its whole nofe in from D to C C, it would not have amounted to the fuppofed thick- nefs of xhzttegument^xht length of the nofe being not more then a three hundredth part of an inch. It has fix legs, covered with a very tranfpa- rentfliell, and joynted exadcly like a Crab’s, orLobfter’s, each leg is divided into fix parts by thefe joynts , and thofe have here and there feveral fmall hairs 3 and at the end of each leg it has two claws, very properly adapted for its peculiar ufe, being thereby inabled to walk very fccurely both on the fkin and hair 5 and indeed this contrivance of the feet is very curious, and could not be made more commodioufly and compendioufly, for performing both thefe requifite motions, of walking and climbing up the hair of a mans head, then it is : for, by having the lefler claw faj fet fo muchfhort of the bigger (b) when it walks on the fkin the Ihorter touches not, and then the feet are the fame with thofe of a Mite, and feveral other finall Infeds, but by means of the fmall joynts of the longer claw it can bend it round, andfb with both claws take hold of a hair, in the manner reprefented in the Figure, the long tranfparent Cylinder F F F, being a Man’s hair held by it.
The Thorax feem’d cas’d with another kind of fubftance then the bel- ly, namely, with a thin tranfparent horny fubftance, which upon the fafting of the Creature did not grow flaccid 5 through this I could plain- ly fee the blood, fuck’d from my hand, to be varioully diftributed, and mov’d to and fro 5 and about G there feem’d a pretty big white fub- ftance, which feera’d to be moved within its ; befides, there ap-
pear’d very many fmall milk-white veflels, which croft over the breaft
between
Schcni. XXX'/
Ml CROGRAPHIA.
between the legs, out of which, on either fide, were many fmall bran- chings,thefe feem'd to be the veins and arteries, for that which is analogus to blood in all Infefts is milk-white.
The belly is covered with a tranfparent fubflance likewjfe,.. but more refembling a Ikin then a (hell , for ’tis grain’d all over the belly like the skin in the palms of a man’s hand, and when the belly is empty ,grows very flaccid and wrinkled^ at the upper end of this is placed chefto- mach H H,and perhaps alfo the white fpot 1 1 maybe the liv&Y.orpanGrear, whichTy the perijialtkk, motion of the guts, is a little mov’d to and fro, not with a and diafiok^ but rather with a thronging or juifiling motion. Viewingoneof thefe Creatures, after it had faded two d ayes, all the hinder part was lank and flaccid , and the white Ipot 1 1 . hardly mov’d, mod of the white branchings difappear’d , and mod alfo of the rednels or focked blood in the guts, the pkijialtkk^ motion of which' was fcarce difcernable 5 but upon the fuflering it to fock , it prefontly fill’d the fl^in of the belly, and of the fix fcolop’d embofments on either fide, as full as it could be duft ^ the domach and guts were as Tull as they could hold 5 the perijialtkl^ motion of the gut grew quick,and the judling motion of 1 1 accordingly 5 multitudes of milk-white vedels feem’d quickly filled, and turgid, which were perhaps the veins andarr teries, and the Creature was fo greedy, that though itcould.not contain more, yet it continued fucking as fad as ever, and as fad emptying it felf behind : the digeftion of this Creature mud needs be very quick, for though I perceiv’d the blood thicker and blacker when dick d, yet,- when in the guts, it was of a very lovely ruby colour, and that part of it, which was digeded into the veinsy feemed whiter whence it appears, that a further digedion of blood may make it milk, at lead of a refem- bling colour : What is elfe obfervable in the figure of this Creature, may be feen by the 3 5. Scheme,
Obferv* LV. Mites*
THe lead of Reptiles I have hitherto met with, is a Mite, a Creature whereof there are fome fo very fmall , that the (harped fight, un= aflided with Glades, isnotabletodilcern them, though, being white of themfelves, they move on a black and fmooth furface ^ and the Eggs, out of which thele Creatures feem to be hatch’d, are yet fmaller, thofe being ulually not above a four or five hundredth part of a well grown Mite, and thofo well grown Mites not much above one hundredth of an inch in thicknels , fo that according to this reckoning there may be no lels then a million of well grown Mites contain’d in a cubick inch, and five hundred times as many Eggs.
Notwithdanding which minutenels a good Microfccpe difeovers thofo fmall movable fpecks to be very prettily (hap’d Infofts, each of them fur-
nifh'd
MiCROGR AP HI A.
nifti’d with eight well fhap’d and proportion’d legs, which are each of them joynted or bendable in eight feveral places^ or joynts, each of which is covered, for themoft part, with a very tranlparent (hell, and the lower end of the fhell of each joynt is fringed with feveral finall hairs 3 the contrivance of the joynts leems the very lame with that of Crabs and Lobft ers legs, and like thole alfo, they are each of them ter- minated with a very lharp claw or point 3 four of thefe legs are fo pla- ced, that they feem to draw forwards, the other four are placed in a quite contrary polition ^ thereby to keep the body backwards when there is occalion.
The body, as in other larger Infects , conlifts of three regions or 3^* parts 3 the hinder or belly A, feems covered with one intire fhell , the middle, or chelt, feems divided into two fhells B C. which running one within the other, the Mite is able to fhrink in and thruft out as it finds occalion, as it can allb the fnout D. The whole body is pretty tranfpa- rent, fo that being look’d on againft the light, divers motions within its body may be perceived 3 as alfo all the parts are much more plainly de- Jineable, then in other poftures, to the light. The Ibcll, efpecially that which covers the back, is curioufly polifhr, fo that ’tis ealie to fee, as in a Looking-glals, ox foliated Glals-ball, the pidure of all the ob- jeds round about 3 up and down, in leveral parts of its body, it has le- veral fmall long white hairs growing out of its fhell , which are often longer then the whole body, and are reprelented too fhort in the firft and lecond Figures 3 they feem all pretty ftraight and plyable, lave only two upon the fore-part of its body, which leem to be the horns, as may be leen in the Figures 3 the firft whereof is a prolped of a fmaller fort of Mites ( which are ufually more plump ) as it W2ispaj]ant to and fro 3 the fccond is the profped of one fixt on its tail ( by means of a little mouth- glew rub*d on the objed plate) exhibiting the manner of the growing of the legs, together with their feveral joynts.
This Creature is very much diverlify’d in Ihape, colour, and divers other properties, according to the nature of the fubftance out of which it leems to be ingendred and nourilhed,being in one fubftance more long, in another more round, in fome mOre hairy, in others more fmooth, in this nimble, in that flow, here pale and whiter, there browner, blacker, more tranfparent, I have obferved it to be relident almofton all
kinds of liibftances that are mouldy, or putrifying, and have leen it very nimbly mefhing through the thickets of mould, and fometimesto lye dormant underneath them 3 and ’tis not unlikely, but that it may feed on that vegetating fobftance , jpontaneous Vegetables leeming a food proper enough for jpontaneous Animals^
But whether indeed this Creature, or any other, be llich or not,. I can- not politively, from any Experiment, or Obfervation, I have yet made, determine. But,as I formerly hinted, it feems probable, that fome kind of wandring Mite may fow, as *twere, the firft feeds, or lay the firft eggs, in thole places , which Nature has inftruded them to know convenient for the hatching and nourilhing their young 3 and though perhaps the
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prime Parent might be of a (hape very differing from what the off- fpring, after a little while, by reafon of the fubftance they feed on, or the Region ( as ’twere ) they inhabited yet perhaps even one of thefe alter’d progeny, wandering again from its native foil, and lighting on by chance the fame place from whence its prime Parent came, and there fet- tling, and planting, may produce a generation of Mites of the fame fhapes and properties with the firft wandring Mire- .* And from fomeluch accidents as thefe, I am very apt to think, themoff forts of Animals, ge- nerally accounted jpofitaneous , \\2LVQx)tit\r origination ^ and all thofe va- rious forts of Mites, that are to be met with up and down in divers pu- trifying fubftances, may perhaps be all of the lame kind, and have Iprung from one and the fame fort of Mites at the firfr.
Obferv. L V I. Of a [mail Creature hatch'd on a Vine,
T Here is, almoft all the Spring and Summer time, a certain fmall, round, white Cobweb, as twere, about the bignefs of a Pea, which fticks very clofe and faft to the frocks of Vines nayfd againfr a warm wall : being attentively viewed,they feem cover d, upon the upper fide of them, with a fmall husk, not unlike the fcale, or fhellof a Wood- loufe, or Hog-loufe , a fmall Infedt ufually found about rotten wood, which upon touching prefently rouls it felfinto the form of a pepper- corn : Separating feveral of thefe from the frock , I found them, with my A/icroJeope^ to confifr of a fhell, which now feemed more likely to be the hufk of one of thefe Infeds .* And the fur feem’d a kind of cobweb, confifring of abundance of fmall filaments, or fleaves of cobwebs. In the midft of this, if they were not hatch’d,and run away before, the time of which hatching was ufually about the latter end of June^ or begin- ning of jhIj/ , I have often found abundance of fmall brown Eggs, fuch as A and B in the focond Figure of the 36. Scheme^ much about the big- nefs of Mites Eggs j and at other times, multitudes of fmall Infeds , fha- ped exadly like that in the third Figure marked with X. Its head large, almoft half the bignefs of its body, which is ufual in the of mofr Creatures. It had two fmall black eyes a and two fmall long joynted and brifled horns b b. The hinder part of its body feem’d to confifr of nine fcales, and the lafr ended in a forked tayl , much like that of a Cu~ tiOy or Wood-loufe, out of which grew two long hairs 5 they ran to and fro very fwiftly, and were much of the bignefs of a common Mite, but fome of them Icfs : The longefr of them feem’d not the hundredth part of an inch , and the Eggs Ufually not above half as much. They feemed to have fix legs, which were not vifible in this I have here deline- ated, by reafon they were drawn under its body.
If thefe Minute creatures were Wood~lice(2iS indeed from their owm friape and fi'ame, the fkin,or fhell,that grows on them, one may v/ith great pro-
ICROGRAHPIA.
bability ghefsj it^affords us an Inftance, whereof perhaps there are not many like in Nature^and that is,of the prodigious increafe of thele Crea- tureSj after they are hatch’d and run about ^for a common Wood-loufcjof about half an inch long, is no lefs then a hundred and twenty five thou- fand times bigger then one of thele, which though indeed it feems very ftrange, yet I have obferved the young ones of fome Spiders have almofi: kept the fame proportion to their Dam.
This, methinks, if it be fo, does in the next place hint a Qu2ery,which may perhaps deferve a little further examination : And that is, Whether there be not many of thofe minute Creatures, fuch as Mites, and the like, \yhich, though they are commonly thought of otherwife , are only the fully ^ or young ones, of fnuch bigger Infers, and not the generating, or parent Inled, that has layd thofe Eggs 5 for having many times ob- forv’d thofe Eggs, which ullially are found in great abundance where Mites are found , it feems fomething ftrange , that fo fmall an Animal Ihould have an Egg fo big in proportion to its body. Though on the other fide, I muft confels, that having kept divers of thofe Mites inclofed in a box for a good while, I did not find them very much augmented be- yond their ufual bignels.
What the husk and cobweb of this little white fubftance (hould be, I cannot imagine, unlefs it be, that the old one, when impregnated with Eggs, Ihould there ftay, and fix it felf on the Vine, and dye, and all the body by degrees fhould rot, fave only the husk, and the Eggs in the bo- dy : And the heat, or fire, as it were, of the approaching Sun-beams fhould vivifie thofe Relifts of the corrupted Parent , and out of the afhes, as ’twere, ( as it is fabled of the Pheemx ) fhould raile a new ofT fpring for the perpetuation of the jpecies. Nor will the cobweb , as it were, in which thele Eggs are inclos’d, make much againft this Con je- fture 5 for we may, by thofe cobwebs that are carried up and down the Air after a Fog (which with my Microfeope I have dilcovered to be made up of an infinite company of fmall filaments or threads ) learn , that liich a texture of body may be otherwife made then by the Ipinning of a Worm.
Obferv. L V 1 1. Of the Eels in Vinegar,
OF thele Imall Eels, which are to be found in divers forts of Vine- gar, I have little to add befides their Pifture, which you may find drawn in the third Figure of the 25. Scheme: That is, they were foaped much like an Eel, lave only that their nole A, ( which was a lit- tle more opacous then the reft of their body ) was a little lharper, and longer, in proportion to their body, and the wrigling motion of their bodyfeem’d to be onely upwards and downwards, whereas that of Eels is onely fide wayes ; 1 hey leem’d to have a more opacous part
about
MiCROGRAPHiA.
about Bp whicli might, perhaps, be their Gills , it Teeming always the fame proportionate diftant from their nole, from which, to the tip of their tail, C, their body Teem’d to taper.
Taking feveral of thefe out of their Pond of Vinegar, by the net of a fmall piece of filtring Paper, and laying them on a black fmooth Glals plate, I found that they could wriggle and winde their body, as much almoft as a Snake, which made me doubt, whether they were a kind of Eal or Leech.
I (hall add no other obfervations made on this minute Animal, being prevented herein by many excellent ones already publilh’d by the inge- nious, Dodor Pon>er, among his Microfcopical Obfervations, fave onely that a quantity of Vinegar repleat with them being included in a fmall Viol, and ftop’d very clofe from the ambient air, all the included Worms in a very Qiort time died, as if they had been fnfled.
And that their motion Teems (contrary to what we may obferve in the motion of all other Infeds) exceeding flow. But the reafon of it Teems plain, for being to move to and fro after that manner which they do, by waving onely, or wrigling their body ^ the tenacity, or glutinouTnefs, and the denfity or refiftance of the fluid medium becomes fb exceeding Tenfible to their extremely minute bodies,that it is to me indeed a greater wonder that they move them fb fafi: as they do,then that they move them no fafler. For what a vafUy greater proportion have they of their Tuper- ficies to their bulk, then Eels or other larger Fifhes, and next, the tena- city and denfity of the liquor being much the Tame to be moved, both by the one and the other, the refiftance or impediment thence arifing to the motions made through it, muft be almoft infinitely greater to the fmall one then to the great. This we find experimentally verify ’d in the Air, which though a medium a thouTand times more rarify ’d then the wa- ter,the refiftance of it to motions made through it,is yetfo fenfible to ve- ry minute bodies,that a Down-feather(the lealt of whole parts Teem yet bigger then thefe Eels, and many of them almoft incomparably bigger, fuch as the quill and ftalk) is TuTpended by it, and carried to and fro as if it had no weight.
Oblerv. L V 1 1 1. Of a new Property in the Air, and feveral other tranjparent Mediums narnd Inflexion, whereby very many con-‘ fiderable Phenomena are attempted to be folvdy and divers other vfes are hinted,
Since the Invention (and perfecting in fbme meafiire) of Telejcopes^ it has been obferv’d by feveral, that the Sun and Moon neer the Horizon, are disfigur’d C lofing that exaCHy-fmooth terminating circular limb, which they are obferv’d to have when fituated neerer the Zenith) and are bounded with an edge every way (efpecially upon the right and left
G g flfles)
2i8
Micrographia.
(ides) ragged and indented like a Saw : which inequality of their limbs, I have further obferv d, not to remain always the fame, but to be conti- nually chang’d by a kind of fludfuating motion, not unlike that of the waves of the Sea , fb as that part of the limb, which was but even now nick’d or indented in, is now protuberant, and will prefently be finking again 3 neither is this alhbut the whole body of the Luminaries, do in the Telefcope^ feem to be deprefs’d and flatted, the upper,and more elpecially the under fide appearing neerer to the middle then really they are,and the right and left appearing more remoterwhence the whole j^reaieems to be terminated by a kind of OvaUt is further oblerv’d.that the body,fbr the moff part, appears red, or of fome colour approaching neer unto it, as feme kind of yellow 3 and this I have always mark'd, that the more the limb is flatted or ovalled,the more red does the body appear, though not always the contrary. It is further obfervable, that both fix'd Stars and Planets, the neerer they appear to the Horizon, the more red and dull they look, and the more they are obferv’d to twinkle 3 in fb much, that I have feen the Dog-fiarr to vibrate fb ffrong and bright a radiation of light, as almofi: to dazle my eyes, and prefently, almofi: to difappear. It is alfb obfervable, that thofe bright fcintillations neer the Horizon, are not by much fb quick and fudden in their confecutions of one another, as the nimbler twinklings of Stars neerer the Zenith. This is alfb notable, that the Starrs neer the Horizon, are twinkled with feveral colours 5 fb as fbmetimes to appear red,fbmetimes more yellow,and fometimes blue,and this when the Starr is a pretty way elevated above the Horizon. I have further, very often feen fome of the fmall Starrs of the fifth or fixth ma- gnitude, at certain times to difappear for a fmall moment of time, and again appear more confpicuous, and with a greater lufter. I have feveral times,withmy naked eye, feen many fmaller Starrs, fuch as may be call’d of the feventh or eighth magnitude to appear for a fhort ff>ace, and then vanifh, which, by directing a fmall Tekfeope towards that part they ap- pear’d and difappeard in 3 1 could prefently find to be indeed fmall Starrs fb fituate.as I had feen them with my naked eye, and to appear twinkling like the ordinary vifible Stars 3 nay, in examining fbme very notable parts of the Heaven, with a three foot Tube, me thought I now and then, in feveral parts of the conftellation, could perceive little twinklings of Starrs, making a very fhort kind of apparition, and prefently vanifhing, but noting diligently the places where they thus feem’d to play at boe- peep, I made ule of a very good twelve foot Tube, and with that it was not uneafie to fee thofe, and fe veral other degrees of fmaller Starrs, and fome fmaller yet, that feem’d again to appear and difappear, and thefe alfb by giving the fame Objed-glafs a much bigger aperture, t could plainly and conftantly fee appear in their former places, fo that I have obferv'd fbme twelve feveral magnitudes of Starrs lefs then thofe of the fix magnitudes commonly recounted in the Globes.
It has been obferv’d and confirm’d by the accurateff Obfervati- ons of the beft of our modern Aftronomers, that all the Luminous bodies appear above the Horizon, when they really are below it. So that the
Sun
MiCROGRAP H I A. 2i
Sun and Moon have both been feen above the Horizon, whil'ft the Moon has been in an Eclipfe. I fhall not hereinftance in the great refraftions, that the tops of high mountains, ieen at a dilfance, have been found to have 5 all which feem to argue the Horizontal refraction, much greater then it is hitherto generally believ’d.
I have further taken notice, that not onely the Sun, Moon and Starrs, and high tops of mountains have iuffer’d thefe kinds of refradtion, but Trees, and feveral bright Objcdts on the ground ; I have often taken no- tice of the twinkling of the rcfledcions of the Sun from a Glafs-windovv at a good diftance,and ofa Candle in the night, but that is not focon- fpicuous.and in obferving the fettingSun,! have often taken notice of the tremulation of the Trees and Bufhes, as well as of the edges of the Sun. Divers of thefe rh£nowet2a taken notice of by ieveral, who
have given feveral reafons of them, but I have not yet met with any alto- gether farisfadirory, though lome of their corijedfures have been partly true,but parly alio falfe.betting my lelf therfore upon the inquiry of thele Vh£KOMcna^ I hrfl: endeavour’d to be very diligent in taking notice of the feveral particulars and circum.ftances obfervable in them 5 and next, in making divers particular Experiments, that might deer Ibme doubts, and ferve to determine, confirm, and illufirate the true and adequate caufe of each 5 and upon the whole, I find much reafon to think, that the true caufe of all thefe Vh£r7omef?a is from the or mnlti-
plicate refraBion of thofe Rays of light within the body of the Atmojphere^ and that it does not proceed from, a 7'efiaBion caus’d by any terminating fnperficies of the Air above, nor from any fuch exadlly defin’d fuperficies within the body of the Atfnofphere.
This Conclufion is grounded upon thefe two Propofitions :
Firft, that a medmm^ whole parts are unequally de77fe^ and mov’d by various motions and tranfpolitions as to one another, will produce all thefe vifible efiefts upon the Rays of light, without any other coeficient caule.
Secondly, that there is in the Air or Atff/ojphere, iuch a variety in the conftituent parts of it, both as to their def?jity and rarity^ and as to their divers mutations and pofitions one to another^
By DetTjity and Rarity^ I underftand a property of a tranfparent body, that does either more or left refrad a Ray of light (coming obliquely upon its fuperficies out of a third ntedinni) toward its perpendicular ; As I call Glals a more denfc body then Water, and Water a more rare body then Glafs, becaufe of the refradf ions (more or lefs deflecf ing towards the perpendicular) that are made in.them,of a Ray of light out of the Air that has the lame inclination upon either of their fuperficies.
So as to thebulincls of Reflation, fpirit of Wine is a more denfe body then Water,it having been found by an accurate Inlfrumcnt that meafures theanglesof Refractions to Minutes that for the fame refraCced angle of 30.* 00' in both. Me dinws^ the angle of incidence in Water was
but 41°. 3'5« but the angle of the incidence in the trial with fpirit of Wine was 42° .■ 45'. But as to gravity, Water is a more denfe. body then
G g 3 Ipirk
220
Micrographia.
fpirit of Wine, for the proportion of the fame Water, to the fame very well rectify 'd fpirit of Wine was, as 21. to 19.
So asto Rcfradion,Wateris more Denfe then Ice, fori have found by a moft certain Experiment, which I exhibited before divers illuftrioiis Perlbnsofthe Royal Society^ that the Refl ation of Water was greater then that of Ice, though fome confiderable Authors have affirm’d the con- trary, and though the Ice be a very hard, and the Water a very fluid body.
That the former of the two preceding Propofitions is true, may be ma- nifefted by feveral ExperimentsrAs firftdf you take any two liquors differ- ing from one another in denfity,but yet fuch asjwill readily mixras Salt Wa- ter,or Brine,8cFrefh5almoft any kind of Salt diflolv’d in Water, and filtra- ted, fb that it be cleer,fpirit of Wine and Water 5 nay, fpirit of W’ine,and fpirit of Wine, one more highly reffify’d then the other, and very many other liquors ^ if(I fay) you take any two of thefe liquors, and mixing them in a Glafs Viol, againft one fide of which you have fix’d or glued a fmall round piece of Paper, and fhaking them well together (fo that the parts of them may be fomewhat diflurb’d and move up and down)you endeavour to fee that round piece of Paper through the body of the li- quors 5 you lhall plainly perceive the Figure to wave, and to be indented much after the fame manner as the limb of the Sun through a Telefcope feems to be,fave onely that the mutations here,are much quicker. And if^ in fteed of this bigger Circle, you take a very Imall fpot, and faften and view it as the former, you will find it to appear much like the twinkling of the Starrs, though much quicker : which two Phenomena (for I fhall take notice of no more at prelent, though I could inftance in multitudes of others) mull: neceflarily be caus d by an i'nfleBjon of the Rays within the terminating luperficics of the compounded medium^ fince the lurfaces of the tranfparent body through which the Rays pafs to the eye, are not at all altered or chang’d.
This jr7pe£fion (ifl may lb call it) I imagine to be nothing ellc, but a nmlupltcatc repraUion^ caufed by the unequal dcnfty of the conftituent parts of the medium , whereby the motion, adtion or progrels of the Ray of light is hindred from proceeding in a flreight line, and infie&ed orde^ fieStedhy a curve. Now, that it is a curve line is manifefl: by this Expe- riment : I took a Box, fuch as A D G E, in the firll: Figure of the Scheme^ whofe fides A B C D, and E F G H, were made of two fmooth flat plates of Glals, then filling it half full with a very ftrong Iblution of Salt, I filled the other half with very fair frelh water, then expofing the opacous fide, D H G C, to the Sun, I oblerv’d both the repaUion and iupethon of the Sun beams,! D & K H, and marking as exadly as I.could, the points, P, N, O, M, by which the Ray, K H, palled through the com- pounded medium^ I found them to be in a curve line 5 for the parts of the medium being continually more denle the neerer they were to the bot- tom, the Ray p f was continually more and more deflefted downwards from the Iheight line.
This Inflexion may be mechanically explained, cither by Monfieur
Des
• IfAXXV • iu^c^P$
(
A
MlCROGRAPHIAi
Des Cartes principles^by conceiving the Globuls of the third Element to find lefs and lefs refiftance againft that fide of them which is downwards or by a way, which I have further explicated in the Inquifition about Co- lours, to be from an obliquation of the pulfe of light, whence the ruder part is continually promoted, and confequently refradcd towards the perpendicular, which cuts the Orbs at right angles. What the particu- lar Figure of the Curve line^ defcrib’d by this way of light, is, I (hall not now hand to examine, efpecially fince there may be fo many forts of it as there may be varieties of the Pofitions of the ifitcrmediat degrees of den- fity and rarity between the bottom and the top of the infiefting Medium.
I could produce many more Examples and Experiments, to illuftratc and prove this firft Propofition, vi%, that there is fiich a conffitution of Ibmc bodies as will caule infieftion. As not to mention thofe I have ob- ferv’d in Horn^ lortoife-Jl.iell^ tranjparent Gums^ and resinous Subjiances ; The veins oi Glals, nay, of melted Cryjial^ found, and much complained of by Glals-grindcrs, and others, might fufficiently demonlfrate the truth of it to any diligent Obfervator.
But that, I prefume, I have by this Example given proof fufficient ( viz. ocular demonjiration ) to evince, that there is fuch a modulation, or bending of the rayes of light , as I have call’d infleBion^ differing hot\i{xoTO. reflection j dudrefraBion (fince they are both made inthefu- perficies, this only in the middle ) ^ and likewife, that this is able or fuf- ficient to produce the effedts I have aferibed to it.
It remains therefore to Ihew , that there is fuch a property in the Air, and that it is fufficient to produce all the above mentioned Thanomena^ and therefore may be the principal, if not the only caufe of them.
Firft, That there is fuch a property, may be proved from this, that the parts of the Air are fome of them more condens’d, others more rarified, either by the differing heat, or differing preffure itfuftains, or by the fomewhat heterogeneous vapours interfpers’d through it. For as the Air is more or lefs rarified, fo does it more or lefs refradf a ray of light ( that comes out of a denfer medium) from the perpendicular. This you may find true, if you make tryal of this Experiment.
Take a fmall Glafs-bubble , made in the form of that in the fecond Figure of the 57. Scheme^ and by heating the Glafs very hot, and there- by very much rarifyingthe included Air, or, which is better, -by rarify- ing a fmall quantity of water, included in it, into vapours, which will expel the moff part, if not ail the Air , and then fealing up the fmall neck of it, and letting it cool, you may find, if you place it in 2. conve- nient Inftrument, that there will be a manifefi: difference, as to the reffa- dion.
As if in this fecond Figure you fuppofe A to reprefent a friiall fight or hole, through, which the eye looks upon an objedf, as C, through the Glafs-bubble B, and the fecond fight L ^ all which remain exadly fixt in their feveral places, the objeff C being fb cized and placed, that it may juft feemto touch the upper and under edge of the hole L : and fo all of it be feen through the fmall Giafs-ball of rarified Air 5 then by
breaking
222
f'i 3-
MiCROGR AP H I A.
breaking off the fmall feal’d neck of the Bubble ( without at all ftirring the fights, object, or glafs J and admitting the external Air, you will find your felf unable to fee the utmoft ends of the objeft 5 but the termi- nating rayes A E and A D ( which were before refracted to G and F by the ratified Air ) will proceed almofl direftly to I and H ^ which al- teration of the rayes ( feeing there is no other alteration made in the Organ by which the Experiment is tryed, fave only the admiffion, or ex- clufion of the condens’d Air ) mud neceflarily be caufed by the variation of the medium contain’d in the Glafs B 5 the grcatcft difficulty in the ma- king of which Experiment, is from the uneven furfaces of the bubble, which will reprefent an uneven image of the objed.
Now,that there is fiich a difference of the upper and under parts of the Air, is clear enough evinc’d from the late improvement of the Torricellian Experiment, which has been tryed at the tops and feet of Mountains 5 and may be further illuftrated , and inquired irito, by a means, which fbme whiles fince I thought of, and us d, for the finding by what degrees the Air paflcs from fuch a degree of Denfity to fuch a degree of Rarity. And another, for the finding what prefliire was requifite to make it pals from fuch a degree of Rarefaction to a determinate Denfity ; Which Experiments, becaufe they may be ufeful to illuftrate the prefent Inqui- ry, I (hall briefly deferibe.
I took then a fmall Glafs-pipe A B, about the bignefs of a Swans quill, and about four foot long, which was very equally drawn, fo that, as far as I could perceive , no one part was bigger then another ; This Tube f being open at both ends) I fitted into another fmall TubeDE, that had a fmall bore juft big enough to contain the fmall Pipe, and this was feal’d up at one, and open at the other, end ; about which open end I faftned a fmall wooden box C with cement, fo that filling the bigger Tube, and part of the box, with Quickfilver, I could thruft the fmaller Tube into it, till it were all covered with the Quickfilver .* Having thus done, I faftned my bigger T ube againft the fide of a wall , that it might ftand the fteadier , and plunging the fmall Tube deer under the Mercu- ry in the box, I ftopt the upper end of it very faft with cement, then lifting up the fmall Tube, I drew it up by a fmall pully, and a firing that I had faftned to the top of the Room, and found the height of the Mer- curial Cylinder to be about twenty nine inches.
Then letting down the Tube again, I opened the top, and then thruft down the fmall Tube, till I perceived the Quickfilver to rife within it to a mark that I had plac’d juft an inch from the top^and immediately clap- ping on a fmall peice of cement that I had kept warm, I with a hot Iron feal’d up the top very faft, then letting it cool (that both the cement might grow hard , and more efpecially , that the Air might come to its temper, natural for the Day I try’d the Experiment in ) I obferv’d dili- gently, and found the included Air to be exaCcly an Inch.
Here you are to take notice, that after the Air is feal’d up, the top of the Tube is not to be elevated above the fuperficies of the Quickfilver
'm
Micrographia.
in the boxj till the furface of that within the Tube be equal to it, for the Quickfilver ( as I have chewhere prov’d ) being more heterogene- ous to theGlals then the Air, will not naturally rile upfb high within the fmall Pipe,as the fuperficies of the Mercury in the box , and therefore you are to obferve , how much below the outward fuperficies of the Mercury in the box, that of the lame in the Tube does ftand, when the top being open, free ingrefs is admitted to the outward Air.
Having thus done, I permitted the Cylinder^ or fmall Pipe, to rile out of the box, till I found the furface of the Quickfilver in the Pipe to be two inches above that in the box, and found the Air to have expanded it lelf but one fixteenth part of an inch 5 then drawing up the frhall pipe, till I found the height of the Quickfilver within to be four inches above that without, I oblerved the Air to be expanded only f of an inch more then it was at firfi: , and to take up the room of 17 inch: then I raifed the Tube till the Cylinder was fix inches high, and found the Air to take up if inches of room in the Pipe 5 then to 8, 10, A2. d^c. the expanfion of the Air that I found to each of which Cylinders are let down in the following Tables where the firfi: row lignifies the height of the Mercurial Cylinder 3 the next, the expanfion of the Air j the third, the prellure of the Atmojphere ^ or the highefi Cylinder of Mercury^ which was then necr thirty inches : The lafi fignifies the force of the Air fo expanded , which is found by fubfirafting the firfi row of numbers out of the third , for having found, that the outward Air would then keep up the Quickfilver to thirty inches , look whatever of that height is wanting mufi be attributed to the Elater of the Air deprelling. And therefore having the Expanfion in the fecond row,and the height of the lubjacent Cylinder of Mercury in the firfi,' and the greatefi height of the Cylinder of Mercury^ ^which of it lelf counterballances the whole prefliire of the Atmojphere , by lubfirading the numbers of the firfi row out of the numbers of the third, you will have the meafure of
lb deprefi, and confequently the force of the Air,in the fev.eral Ex- panfions, regiftred.
Co
i.
sr
o J
-62 „ A r>
The
224
MlCROGRAPHlA.
|
The height of the |
The Expan- ^ |
The height of |
The ftrength |
|
Cylinder di Met ~ |
fion of the |
the Mercury |
of the Elater |
|
that, together Air. |
that counter- |
of the expan* |
|
|
with the Elater of the included Air, ballanced the preflure of the Atmofphere. L _ . .J |
ballanc’d die Atmofphere 1^ |
ried Air. |
|
|
00 |
01 |
30 |
3^0 |
|
02 |
01-, 16 |
30 |
28 |
|
04 |
OI~ 7 |
30 |
26 |
|
06 |
012 |
30 |
24 |
|
08 |
oii X |
30 |
22 |
|
10 |
012 iZ |
30 |
20 |
|
12 |
01^ 3 |
30 |
18 |
|
H |
01 L 6 |
30 |
16 |
|
16 |
022 27 |
30 |
H |
|
18 |
022 |
30 |
12 |
|
20 |
03 |
3° |
10 |
|
22 |
30 |
8 |
|
|
24 |
05 :T |
30 |
6 |
|
25 |
0^2 |
30 |
5 |
|
2^ |
082 X |
30 |
4 |
|
092 |
30 |
3r |
|
|
loi 4 |
30 |
3r |
|
|
26*- 4 |
^3 |
30 |
3r |
|
27 |
*Sr |
30 |
3 |
height
225
M I C R O G R A P H 1 A.
I had leveral other Tables of my Obfervations , and Calculations, which I then made 5 but it being above a twelve month lince I made them 5 and by that means having forgot many circumftances and par» ticulars , I was refolved to make them over once again , which I did An^fi the fecond 1 66 1. with the very lame Tube which I ufed the year before, when I firft made the Experiment ( for it beirig a very good one, I had carefully preferv’d it; ) Arid after having tryed itbVerand over again 5 and being not well fitisfied of feme particulars, I, at laft, having put all things in very good order, and being as attentive, and obfervant, as poffibly 1 could^ of every circumftanee requifite to be ta- ken notice of did regifter my leveral Obfervations in this following Tablb. tri the making of which^ IdM not ekaftly/bllow the method that I had tiled at firft 5 buf having lately heard of Mr. Townly^ Hj/po- thejis^ llhap'd my courfeinfuch fort, as would be moft convenient for the examination of that Hypothejis ^ the event of which you have in the latter part of the laft Tables
The other Experiment was, to find what degrees of force were requi- fite to comprels, or condenfe, the Air into fuch or fuch a bulk.
The manner of proceeding therein v/as this : 1 took a Tube about five foot long, one of whole ends was lealed up, and bended in the form of a syphon , much like that reprelented in the fourth Figure of the 57,. Scheme^ one fide whereof A D, that was open at A, was about fifty inches long, the other fide B C, fhilt at B, was not much above leven in- ches long, then placing it exiEdy perpendicular , I pour’d in a little Quickfilver, and found that the Air B C was 6^ inches, or very near to (even 5 then pouring in Quickfilver at the longer Tube, I continued filling of it till the Air in the Ihorttrpart of it was hontraftecl into half the former dimenfions, and found the height exactly nine and twenty in- ches 5 and by making feveral other tryals, in feveral other degrees of condenfation of the Air, I found them exaftly anfwer the former Hypo- thejis.
But having (by realbn it was a good while lince 1 firft madej forgot- ten many particulars.and being much 'unlatisfied in others, I made the Ex- periment over agaih, and, from the feveral tryals, ^olleded the former part of the following Table ; Where in the row next the left hand 24. fignifi'es the dimenfions of the Air, fuftainingonly thepreflure Of the At- mojphere^ which at that time was equal to a CylindB'rXyi Mercury of nine and tvyenty inches ; The next Figure above it ( 20.) was the diraenfi- ons of the Air induring the firft compreliion, made by a Cylinder Mer- cury 5 A high, to which theprefiiife of the Atmojf ijere nine arid twenty inches being added 5 the elaftick ftr'erigth of the Afr fo comprdft vVill be ' found 341^6, &c.
A
226 Micrograph, I A.
A Table of the Elafiick^ pwer of the Air^
both Experimentally and Hypothetically calculated^ according to its various Dimenftons.
|
The dimen- |
The heighc |
The Mercu- |
The fum |
What they |
|
lions of the |
of the Mer- |
rial Cylinder |
or diffe- |
ought to |
|
included |
curial Cylin- |
added , or |
rence of |
be accor- |
|
Air, |
der counter- |
taken from |
thefe two |
ding to |
|
pois’d 1 by |
the former. |
Cylinders, |
the |
|
|
the Atmo- |
tbefis. |
|||
|
'iA |
fphere. |
[ |
||
|
12 |
29 t |
29 rr |
58 |
S8 |
|
13 |
29 t |
24^'=^ |
53S |
53f, |
|
14 |
29 t |
20,^- |
49s |
49r |
|
16 |
29 t |
H — |
43 |
43r |
|
18 |
29 + |
9.— |
38.- |
38r |
|
20 |
29 t |
s.^= |
34A |
34r |
|
24 |
29 |
0 — |
29 |
29 |
|
48 |
29— |
i4f= |
14^ |
i4r |
|
29— |
22l~ |
6.^ |
7r |
|
|
192 |
20- — |
251- = |
3r |
3r |
|
384 |
29— |
27a— |
il 4 |
|
|
29'- |
27r= |
IL t |
||
|
768 |
29 — , |
28,-- |
OL 8 |
oi s |
|
960 |
29— |
<^f |
||
|
1152 |
29— |
O- l(S j |
From
Micrograph! At
From which Experiments, I think, we may fafely conclude, that the Elater of the Air is reciprocal to its extenfion, or at leaft very neer. So that to apply it to our prefent purpofe ( which was indeed the chief caufe of inventing thefe wayes of tryal ) we will fuppole a in-
definitely extended upwards, [I fay a Cylinder^ not a piece of a Cone^ becaufe, as I may ellewhere fhew in the Explication of Gravity, that tri- plicate proportion of thefhelsof a Sphere, to their refpeftive diameters^ I luppofe to be removed in this cale by the decreale of the power of Gra- vity 3 and the preflure of the Air at the bottom of this Cylinder to be ftrong enough to keep up a Cylinder Mercury of thirty inches ; Now becaufe by the moft accurate tryals of the moll: illuftrious and incompa- rable Mr. 'Eoyle^ publifhed in his defervedly famous Pneumatick Bookj the weight of Quickfilver, to that of the Air here below, is found neer about as fourteen thouland to one : If we luppofe the parts of the Cy- linder of the Atmojfhere to be every where of an equal denlity, we (hall ( as he there deduces ) find it extended to the height of thirty five thouland feet, or feven miles : But becaufe by thefe Experiments we have fbmewhat confirm’d the hypothefis of the reciprocal proportion of the Elaters to the Extenfions we fhall find, that by fuppofing this of
the Afunojphere divided into a thoufand parts, each of which being^ equi- valent to thirty five feet, or feven geometrical paces,that is,each of thefe divifions containing as much Air as is fuppos’d in a Cylinder neer the earth of equal diamcter,and thirty five foot high, we fhall find the lower- moft toprefs againftthe fiirface of the Earth with the whole weight of the above mentioned thoufand parts 5 the preflure of the bottom of the fecond againft the top of the firft to be icoo— 1^^999. of the third againft the fecond to be 1000 — 2 1H998. of the fourth againft the third to be 1000 -3=1997. of the uppermoft againft the 999. or that next be- low it, to be icoo — 999—1. fo that the extenfion of the lowermoft next the Earth, will be to the extenfion of the next below the upper- moft, as I. to 999. for as the preflure fuftainedby the 999. is to the preflure fuftain’d by the firft , fo is the extenfion of the firft to the ex- tenfion of the 999. fo that, from this hypothetical calculation, we fhall find the Air to be indefinitely extended : For if we fuppofe the whole thicknefsof the Air to be divided, as I juft nowinftanced, into a thou- iand parts, and each of thofe under differing Dimenlions, or Altitudes, to contain an equall quantity of Air, we fhall find, that the firft Cylinder^ whole Bale is fuppofed to lean on the Earth, will be found to be exten- ded 35^ foot 3 the fecond equal Divifion, or Cylinder^ whole bajis is fuppofed to lean on the top of the firft,fhall have its top extended higher by 35^3 the third 35*®^ 3 the fourth 3559*3 and fo onward, each e- qual quantity of Air having its dimenlions meafured by 35. and fbme additional number expreft alwayes in the manner of a fraftion , whole numerator isalway the number of the place multipU’d by 35. and whole denominator is alwayes the preflure of the Atntejphere fuftain'd by that part, fo that by this means we may eafily calculate the height of 999. divifions of thofe looo. divifions, I fuppos’d 3 whereas the uppermoft
H h 2 may
Ml CROGRAP HIA.
may extend it felf more then as high again5nay, perhaps indefinitely, or beyond the Moon 5 for the Elaters and Expanfions being in reciprocal proportions, fince we cannot yet find the plus ultra^ beyond which the Air will not expand it felf, we cannot determine the height of the Air; for fince, as we have fhewn, the proportion will be alway as the prefliire fhftain'd by any partis to 35. fo icoo. to the expanfionof that part 5 the multiplication or prodiid therefore of the prefiure, and expanfion, that is, of the two extream proportionals, being alwayes equal to the product of the means, or 35000. it follows. Cnee that Redangle or Produdmay be made up of the multiplication of infinite diverfities of numbers, that the height of the Air is alfb indefinite 5 for fince (as far as I have yet been able to try) the Air feems capable of an indefinite Ex- panfion, the prefliire may be decreafed in infinitum^ and ccnfequently its expanfion upwards indefinite alfb.
There being therefore fuch a difference of denfity, and no Experi- ment yet known to prove a Saltus^ orfkipping from one degree of rari- ty to another much differing from it, that is, that an upper part of the Air fhould fo much differ from that immediately JubJaceut to it, as to make a diftind fuperficies, fuch as we obferve between the Air and Wa- ter, But it being more likely, that there is a continual increafeof
rarity in the parts of the Air, the further they are removed from the fiirfaceof the Earth; It will hence necefl&rily follow, that (as in the Experiment of the fait andfrefh Water) the ray of Light paffing ob- liquely through the Air alfb, which is of very different denfity, will be continually, and infinitely infleded, or bended, from a ffreight, or diredt motion.
This granted , the reafon of all the above recited Pheenomena , con- cerning the appearance of the Celeftial Bodies, will very eafily be de- duced. As,
Firft, The rednefs of the Sun, Moon, and Stars, will be found to be caufed by the infledion of the rays within the Atmojphere» That it is not really in or near the luminous bodies, will, Ifuppofe, be very eafily granted, feeing that this rednefs is obfervable in feveral places differing in Longitude, to be at the fame time different, the fetting and rifing Sun of all parts being for the mofl: part red ;
And fccondly. That it is not meerly the colour of the Air interpos’d, will, Ifuppofe, without much more difficulty be yielded, feeing that we may obferve a very great interjiitmus of Air betwixt the Objed arid the Eye, makes it appear of a dead blew, far enough differing from a fedi, or yellow. i >
But thirdly. That it proceeds from the rcfradion,or infledion, of the fays by the Atmojphere^ this following Experiment will, I fuppofe^ luffici- cntly manifeft. - r
Take a fphserical Cryftalline Viol, fuch as is deforib’d in the fifth Fi- gure A BCD, and, having fill’d it with pure clear Water, expofo it to the Sun beams 5 then taking a piece of very fine Venice Paper, apply it againft that fide of the Globe that is oppofite to the Sun, as againfl: the
fide
Micrograph i a;
fide B C, and you mail perceive a bright red Ring to appears caus’d by the refradion of the Rays, A A A A, which is made by the Globe 5 in which Experiment, if the Glafs and Water be very deer, fo that there be no Sands nor bubbles in the Glal^ nor dirt in the Water, you fhall not perceive any appearance of any other colour, T o apply which Experi- ment, we may imagine the Jtm^fphere to be a great tranlpajrent Globe, which being of a fubftance more denfc then the other, or (which comes to the fame) that has its parts more denfe towards the middle^ the Sun beams that are tangents, or next within the tangents of this Globe,will be refradedor infleded from their dired pafiage towards the center of the Globe, whence, according to the laws of relfadions made in a trian- gular and the generation of colour fet down in the defeription of Mulcovi-glafs,there muft necefiarily appear a red colour in thetranptus or paflage of thofe tangent Rays. To make this more plain, wc willliip- pofe (in the fixth Figure) A B C D, to reprefent the Globe of the mofphere^ E F G H to reprefent the opacous Globe of the Earth, lying in the midft of it, neer to which, the parts of the Air, fuftaining a very great preflure, are thereby very much condens’d, from whence thole Rays that are by infiedion made tangents to the Globe of the Earth, and thofe without them, that pals through the more condens’d part of the fxojphere^ as fuppole between A and E, are by reafon of the inequality of the medium^ infleded towards the center, whereby there muft neceP farily be generated a red colour, as is more plainly ftiewn in the former cited place 5 hence whatlbever opacous bodies (as vapours,or!the likej fhall chance to be elevated into thofe parts, will refled a red towards the eye 5 and therefore thole evenings and mornings appear reddeftjthat have themoft ftore of vapours and halituous fubftances exhaled to a conve- nient diftance from the Earthy for thereby the infledion is made the greater, and thereby the colour alfothe more intenfe^and feveralof thole exhalations being opacous, refled leveral of thofe Rays, which, through an Homogeneous tranlparent medium would pals unlecn 5 and therefore we fee, that when there chances to be any clouds lituated in thofe Regions they refled a ftrong and vivid red. Now, though one great caufe of the rednels may be this infledion,yet I cannot wholly exclude the colour of the vapours themfelves, which may have fomething of rednefs in them, they being partly nitrous,and partly fuliginous^ both which fteams tinge the Rays that pals through them, as is made evident by looking at bodies through the fumes of Aquafortis^ or fpirit of Hitre fas the newly menti- oned Illuftrious Perlbn has demonftrated] and allbthroughthe finoak of a Fire or Chimney.
Having therefore made it probable at lead, that the morning and evening rednels may partly proceed from this infledion or refradion of the Rays, we fhall next Ihew, how the Oval Figure will be likewilc cafily deduced.
Suppole we therefore, EFGH in the fixth Figure o£ the ^ysSchentd^^ to reprefent the Earth 5 A B C D, the Atmojpere"^ E I, and E two Rays coming from the Sun, the one from the upper,the other from the neathef
Limb,
MlCROGRAPHl A.
Limb, theie Rays, being by the Atmojphere inflefted, appear to the eye at E, as if they had come from the points, N and O 5 and becaufe the Ray L has a greater inclination upon the inequality of the Atnwfphere then I, therefore mult it fuffer a greater inflexion, and confequently be further elevated above its true place, then the Ray I, which has a left inclination , will be elevated above its true place 5 whence it will follow, that the lower fide appearing neerer the upper then really it is, and the two lateral fides, viz. the right and left fide, fullering no fenfiblc alteration from the infledion, at leaft what it does lulfer, does rather increafe the vifible Diameter then diminilh it, as I (hall (hew by and by, the Figure of the luminous body muft nccefl'arily appear fomewhat Elliptical.
This will be more plain, if in the feventh Eigure of th 37. Scheme we liippole A B to reprefent the fenfiblc Horizon 5 C D E F, the body of the Sun really below it ^ GHIK, the fame appearing above it, elevated by the infledion of the Atmojphere : For if, according to the beft obfcr- vation, we make the vifible Diameter of the Sun to be about three or four and thirty minutes,and the Horizontal reffadion according to be thereabout, or fomewhat more,the lower limb of the Sun E,will be ele- vated to 1 5 but becaufe,by his account, the point C will be elevated but 29. minutes, as having not fo great an inclination upon the inequality of the Air, therefore I G, which will be the apparent reffaded perpendicu- lar Diameter of the Sun,will be left then C G, which is but29. minutcs,and confequently fix or (even minutes (hotter then the unrefraded apparent Diameter. The parts, D and F, will be likewifo elevated to H and K, whole refradion, by reafon of its inclination, will be bigger then that of the point C, though left then that of E,therefore will the femidiameter I L, be fhorter then L G, and confequently the , under fide of the appearing Sun more flat then (he upper. ^
Now, becaufe the Rays from the right and left fides of the Sun, have been obforv'd by Ricciolo and Crimaldus^ to appear more diftant one from another then really they are,though(by very manyObfervations that I have made for that purpofe,with a very good fitted with a
divided Ruler) I could never perceive any great alteration, yet there be- ing really fome,it will not be amifs,to fhew that this alfo proceeds from the refradion or infledion of the Atmojphere 5 and this will be manifcft,if we confider the Atmojphere as a tranfparent Globe, or at leaft a tranfparent fhell, encompafting an opacous Globe, which, being more dcnle then the medium encompalling it, refrads or infleds all the entring parallel Rays into a point or focus, fo that wherefoever the Oblervator is plac’d within the Atmofphere^ between the focus and the luminous body, the lateral Rays muft neceffarily be more converg’d towards his eye by the refradi- on or infledion, then they would have been without it 5 and therefore the Horizontal Diameter of the luminous body muft neceflarily be aug- mented. ^
This might be more plainly manifeft to the eye by the fixth Figure^ but becaufe it would be Ibmwhat tedious, and the thing being obvious ^ enough
Micrographia*
enough to be imagin’d by any one that attentively confiders it, I fliall ra- ther omit it, and proceed to Ihew, that the mafs of Air neer the furface of theEarth,confifts,or is made up,of parcels,which do very much differ from one another in point of denfity and rarity 5 and confequently the Rays of light that pafs through them will be varioufiy inflefted,here one way, and there another, according as they pafs fo or fb through thofe differing parts^ andthofe parts being always in motion,either upwards or downwards, or to the right or left, or in fome way compounded of thefe, they do by this their motion infledt the Rays, now this way, and prefently that way.
This irregular, unequal and unconffant infledion of the Rays of light, is the reafon why the limb of theSnn^ Moon^ J^piterj Saturn^ Mars^ and Venus ^ appear to wave or dance, and why the body of the Starrs appear to tremulate or twinkle, their bodies,by this means, being foraetimes ma- gnify’d,and fometimes diminifhed 5 fbmetimes elevated, otherwhiles de- prefs d 5 now thrown to the right hand, and then to the left.
And that there is fuch a property or unequal diftribution of parts, is manifeft from the various degrees of heat and cold that are found in the Air i from whence will follow a differing denfity and rarity, both as to quantity and refradion 5 and likewife from the vapours that are inter- pos'd, (whichjby the way, I imagine,as to refradion or infledion, to do the fame thing, as if they were rarify’d Air 3 and that thofe vapours that afccnd,are both lighter, and lefs denfe, then the ambient Air which boys them up ^ and that thofe which defeend, are heavier and more denfe) The firft of thefe may be found true, if you take a good thick piece of Glafs,and heating it pretty hot in the fire, lay it upon fuch another piece ofClafs, or hang it in the open Air by a piece of Wire, then looking upon fome far diftant Objed f fuch as a Steeple or Tree) fo as the Rays from’that Objed pafs diredly over the^lafs before they enter your eye, youfhall find fuch a tremulation and wavering of the remote Objed, as will very much offend your eye ; The like tremulous motion you may obferve to be caus’d by the afeending fleams of Water, and the like. Now, from the firft of thefe it is manifeft, that from the rarifadion of the parts of the Air,by heat, there is caus’d a differing refradion, and from the afeenfion of the more rarify’d parts of the Air, which are thruft up by the colder, and therefore more condens’d and heavie, is caus’d an undula- tion or wavering of the Objed 5 for I think, that there are very few will grant, that Glals , by as gentle a heat as may be endur d by ones hand, fhould fend forth any of its parts in fteams or vapours, which does not feem to be much wafted by that violent fire of the green Glals-hcufe ^ but, if yet it be doubted, let Experiment be further made with that bo- dy that is accounted, by Chymifts and others^ the moft ponderous and fix’d in the world 3 for by heating of a piece of Gold, and proceeding in the fame manner, you may find the fame effeds.
This trembling and fhahing of the Rays, is more fenfibly caus’d by an adual flame, or quick fire, or anything elfe heated glowing hot 3 as by a Candle, live Coal, red-hot Iron, or a piece of Silver, and the like ; the fame alfb appears very confpicuous , if you look at an Gbjed betwixt
which
Micrographia.
which and your eye, the rifing fmoak of Ibme Chimney is interpos’d which brings into my mind what I had once the opportunity to obferve, which was, the Sun rifing to my eye juft over a Chimney that fent forth a copious fteam of fmoak and taking a fhort Tdejeope^ which I had then by me, I obferv’dthe body ofthe Sun, though it was but juft peep d above the Horizon, to have its underfide, not onely flatted^ and preis'd inward, as it ufually is when neer the Earth f but to appear more pro- tuberant downwards then if it had futfered no refraftion at all ^ and belides all this, the whole body of the Sun appear’d to tremble or dance, and the edges or limb to be very ragged or indented, undulating or wa- ving, much in the manner of a flag in the Wind.
This I have likewife often obferv’d in a hot Sunihiny Summer’s day, that looking on an Object over a hot ftone,or dry hot earth,I have found the Objed to be undulated or fhaken, much after the lame manner. And ifyou look upon any remote Ob jed through aTeleJcope (in a hot SUm- liier's day efpeciallyj) you lhall find it likewife to appear tremulous. AUd further, if there chance to blow any wind, or that the air between you and the Objed be in a motion or current, whereby the parts of it, both rarify’d and condens’d, are fwiftly remov’d towards the right or left, if then you obferve the Horizontal ridge of a Hill far diftant,through a very good Telefcope^ you lhall find it to wave much like the Sea, and thole waves will appear to pafs the lame way with the wind.
From which, and many other Experiments, ’tis deer that the lower Re- gion of the Air,elpecially that part of it which lieth neereft to the Earth, has, for the moft part, its conftituent parcels varioully agitated, either by heat or winds, by the firft of which, fome of them are made more rare, and lb fuller a lels relradion 5 others are interwoven, either with afeend- ing ordefeending vapours 5 the former of which being more light, and fo more rarify’d,have likewife a lefs refradion 5 the latter being more hea- vie, and conlequently more denle,have a greater.
Now, becaufethat heat and cold are equally diffus’d every way 5 and that the further it is fpread, the weaker it grows , hence it will follow, that the moft part of the under Region of the Air will be made up of fe- veral kinds of /cwte/, fome whereof will have the properties o{ Cofivex ^ othersoi Concave glajjes which, that I may the more intelligibly make out, we will fuppOfe in the eighth f/^//rcof the Scheme^ that A re- prefents an afeending valour, which, by reafon of its being fomewhat Heterogeneous to the ambient Air,is thereby thruft into a kind ofGiobuIaf form, not any where terminated, but gradually finiftied, that is, it is moft rarity ’d in the middle about A, fomewhat more condens’d about B B, more then that about C C ^ yet furthetjabout D D, almoft of the fame denfity with the ariibient Air about EE:, and laftly, inclofed with the more dcnle Air F F, fo that from A, to F F, there is a continual in- creale of denfity. The reafon of which will be manifeft, if we confider the* rifing vapour to be much warmer then the ambient heavie Air 5 for by thecoldnefsof the ambient Air, the Ihell E E will be more refrigerated then D D,and that then C C, which will be yet more theiiB B, and that
more
Micrographia.
more then A 5 fo that from F to A, there is a continual increafe of heat, and confequently of rarity 5 from whence it will neceflarily follow, that the Rays of light will be inflefted or refraded in it, in the fame man- ner as they would be in a Concave-glafe 5 for the Rays GKI^ G K I will be infleded by G H, G K which will eafily follow from what I be- fore explained concerning the infledion of the Atmojphere.
On the other fide, a defcending vapour,or any part of the air included by an afeending vapourjwill exhibit the fame effeds with a Convex lens 3 for, if we fuppofe,in the former Figure, the quite contrary conftitution to that laft delcriRd 3 that is, the ambient Air F F being hotter then any qpart of that matter within any circle, therefore the coldeft part muft necedarily be A, as being farthefl: remov’d from the heat , all the intermediate fpaces will be gradually difcriminated by the continuall mixture of heat and cold, fo that it will be hotter at E E, then D D, in D D then C C, in C C then B B, and in B B then A. From which, a like refradion and condenfation will follow 3 and conlequently a lefleror greater refradion, fo that every included part will retradmore then the including, by which m.eans the Rays, GK I, GR I, coming from a Starr, or fome remote Objed, are fo infieded, that they will again concurr and meet, in the point M. By the interpofition therefore of this defending vapour the vifible body of the Star, or other Objed, is very much aug- mented, as by the former it was diminifhed.
From the quick conlecutions of thefe two,one after another, between the Objed and your eye,cauled by their motion upwards or downwards, proceeding from their levity or gravity, or to the right or left,procced- ing from the wind, a Starr may appear, now bigger, now lefs, then really it would otherwile without them 3 and this is that property of a Starr, which is commonly call’d twinkling, or fcintillation.
The reafon why aStar will now appear of one colour,now of another, which for the moft part happens when ’tis neer the Horizon, may very eafily be deduc’d from its appearing now in the middle of the vapour, other whiles neer the edge 3 for if you look againft the body of a Starr v/ith a Telejcope that has a pretty deep Convex Eye-glafi, and fo order it,* that the Star may appear fometimes in one place,and Ibmetimesin another of it3you may perceive this Qr that particular colour to be predominant in the apparent Figure of the Starr, according as it is more or left remote from the middle of the Lens. This I had here further explain’d, but that it does more properly belong to another place^
Ifhall therefore onely add fome few Quaeries, which the confideration of thefe particulars hinted, and fo finifh this Sedfion.
And the firfti fhall propound is, Whether there rnay not be made art artificial tranlparent body of an exadt Globular Figure that (hall fo infledt or refradf all the Rays, that,coming from one point, fall upon any Hemijphere of it 3 that every one of them may meet on the oppofite fide, and crofs one another exadfly in a point 3 and that it may do the like alfo with all the Rays that, coming from a lateral point, fall upotv any other Uemijphere '-j for iffo, there were to be hoped a perfedtion o£ Dfoptric^p^
! i and
MiCROGR AP H i.A.
and a tranfmigration into heaven, even whil’ft we remain here upon earth in the flefh, and a defcending or penetrating into the center and inner- moft recefles of the earth, and all earthly bodies ; nay, it would open not onely a cranney, but a large window (as I may fo fpeak) into the Shop of Nature, whereby we might be enabled to fee both the tools and opera- • tors, and the very manner of the operation it felf of Nature 3 this, could it be effeded, would as farr furpafs all other kind of perfpedives as the vaft extent of Heaven does the Imall point of the Earth, which diftance it would immediately remove, and unite them, as ’twere,into one,at lead, that there fhould appear no more diftance between them then the length of the Tube, into the ends of which thefe Glafles fhould be nferted: Now, whether this may not be effeded with parcels of Glals of feveral denfities, I have fometimes proceeded fo farr as to doubt (though in truth, as to the general, 1 have wholly defpaifd of it) for I have often obferv’d in Optical Glafles a very great variety of the parts, which are commonly called Veins 3 nay, fome of them round enough (for they are for the moft part, drawn out into ftrings) to conftitute a kind of lens.
This I fhould further proceed to ope, had any one been fo in- quifitive as to have found out the way of making any tranfparent body, either more denfe or more rare3 for then it might be poflible to compofe a Globule that Ihould be more denfe in the middle of it , then in any other part, and to compofe the whole bulk, fo as that there flioiild be a continual gradual tranfition from one degree of denfity to another 3 fuch as fhould be found requifite for the defired inflexion of the tranjhjigra^ ting Rays 3 but of this enough at prefent, becaufe I may lay more of it when I let down my own Trials concerning the melioration of Dioptrid^s^ where I fhall enumerate with how many feveral fubftances I have made both Microscopes^ and Telefiopesy and by what and how many, ways : Let fuch as have leilure and opportunity farther conlider it.
The next Qusery fhall be, whether by the lame rolledtion of a more denfe body then the other, or at leaft, of the denier part of the ether, there might not be imagin’d a reafon of the apparition of fome new fix’d Stars, as thole in the Swan , CaJJiope's Charr, Serpentarius^ Tifeis , Ce- tus^ &c.
Thirdly, Whether it be poflible to define^ the height of the Jtmojphere from this inflexion of the Rays, or from the Quickfilver Experiment of the rarifadion or extenlion of the Air.
Fourthly, Whether the dilparity between the upper and under Air be not fometimes fo great, as to make a refleding fuperficies 3 I have had fo- veral Obfervations which foem to have proceeded from fome fuch caule, but it would be too long to relate and examine them. An Experiment, alfo fomewhat analogous to this, I have made with Salt-water and Frefh, which two liquorSjin moft Politions,leem-d the fame, and not to be fepa- rated by any determinate luperlicies,whichleparating lurface yet in fome other Pofitions did plainly appear.
And if fo. Whether the reafon of the equal bounding or terminus of the under parts of the clouds may not proceed from this caule 3 whether,
fecondly.
Mrc ROG R.A PHiA.
•fecondly, the Reafbn of the apparition of many Suns may not be found out, by confidering how the Rays of the Sun may fo be refledrcd, as to defcribe a pretty true image of the body,as we find them from any regu- lar Superficies. Whether, alfo this may not be found to caufe the appa- rition of fome of thole Parelii^ or counterfeit Suns, which appear colour red, by refrafting the Rays lb, as to make the body of the Sun appear in -quite another place thenrealJy it is* But of this more elfewhere.
5. Whether the rh^n&mena of. the Clouds may not be made out by this diverfity of denlity in the upper and under parts of the Air, .by iuppofing the Air above them to be much lighter then they themfelves are, and they fheihlelves to be yet lighter then that which is liibjacent TO them, many of them feeming to be the fame fubftance with the Cob- webs that fly in the Air after a F og,
' Now that litch a conftitution of the Air and Clouds, if liich tiiere fae, may be fufficient to perform thiseffed, may be confirm’d by this Expe- riment.
Makeasflrong a Solution of Sahas you are able, then fillinga Glafs
fome depth half full with it, fill the other half with frclh Water, and poyfe a little Glals-bubble, fo as that it may fink pretty quick in frefh Water, which take and put ihto the aforefaid Glafs, and you fhall And it to fink till it comes towards the middle, where it will remain fixt, without rhoving cither upwards or downwards* And by a fecond Ex- periment, of poifing fuch a bubble in watery whole upper part is warmer, and conlequently lighter, then the under, which is colder and heavier 5 the manner of which follows in this next Qusry, which is,
6. Whether the rarifadion and condenfationof W^aterbe not made after the lame manner, as thole effects are produc’d in the Air by heat 5 for I once pois’d a feal'd up Glals-bubble fo exaftly, that never fo Imall an addition would make it fink, and as fmall a detraffion make it fwim, which liiffering to reft in that Veflel of Water for fome time , lalwayes foundit about noon to be at the bottom of the Water, and at night, and fo the morning, at the top : Imagining this to proceed from the Rari- fadlion of the Water, caus’d by the heat , I made tryal, and found moft true 5 for I was able at any time, either to deprefs, or raife it, by he*at and cold ; for if I let the Pipe ftand for fome time in cold water, I could eafily raife the Bubble from the bottom, whither 1 had a little a- fbre detruded it, by putting the fame Pipe into warm Water. And this way I have been able, fora very confiderable time, to keep a Bubble fo poys’d in the Water, as that it ftiould remain in the middle, and neither link, nor fwim : For gently heating the upper part of the Pipe with a Candle, Coal, or hot Iron^ till I perceived the Bubble begin to defeend, then forbearing, I have obferved it to defeend to fuch or ftich a ftatiori, and there to remain fulpended for fome hours, till the heat by degrees were quite vaniflied , when it would again afeend to its former place. This I have alfo often obferved naturally performed by the heat of the Air, which being able to rarifie the upper parts of the Water fboner then the lower , by reafon of its immediate contaff , the heat of the Air
I I 5 ' has
f
M l-C ROGRAPHIA.
has fometimes fo OowTy increafed, that I have obferved the Bubble to be fome hours in paffing between the top and bottom.
7. Whether the appearance of the of "Temrify and feverai other high Mountains, at fo mudh greater a diftance then feems to agree with their refpedive heights be not to be attributed to t\it. Curvature of the vifual Ray, that is made by its palling obliquely through lb differingly Denje a Medium from the top to the eye very far diftant in the Hori- zon : For lince we have already, I hope, made it very prdbable , . that there is fuch 2iumjte£tion of the Rays by the differing denfity of .the parts of the Air 5 and lince I have found , by feverai Experiments made on places comparatively not very high, and have yet found the prelEire fuftain d by thofe parts of the Air at the top and bottom , and allb their differing Expanlions very conliderable : Infomuch that I have found the prellure of the Atmofphere lighter at the top of St. P^»/’s Steeple, in don ( which is about two hundred foot high ) then at the bottom by a fixtieth or fiftieth part, and the expanfion at the top greater then that at the bottom by neer about fo much alfo 5 for the Mercurial Cylinder at the bottom was about 5 9. inches, and at the top halfan inch lower 3 the Air allb included in the Weather-glafs,that at the bottom fill d only 155. Ipa- ces, at the top fill’d 158. though the heat at the top and bottom was found exaftly the fame witha fcafd Thermometer: I think it very rational to fuppofe , that the greateft Curvature of the Rays is made neareft the Earth,and that the inflection of the Rays, above 5. or 4. miles upwards, is very inconfiderable, and therefore that by this means fuch calculations of the height of Mountains, as are made from the diftance they are vilible in the Horizon,from the fuppolal that that Ray is a ftraight Line ( that from the top of the Mountain is, as'twere, a Tangent to the Horizon whence it is feen) which really is a Curve^ is very erroneous. Whence, I fuppofe,pro- ceeds the reafon of the exceedingly differing Opinions and AllCrtionsof feverai Authors, about the height of feverai very high Hills.
8. Whether this Inflexion of the Air will not very much alter the fup-
polcd diftances of the Planets, which feemto have a very great depen- dence upon the Hypothetical refradlion or inflexion of the Air, and that refraffion upon the hypothetical height and denfity of the Air ; For lince ( as I hope ) I have here Ihewn the Air to be quite otherwife then has been hitherto iuppos’d, by manifefting it to be, both of a vaft. , at leaft an uncertain, height, and of an unconftant and irregular denfity 5 It muft neceflarily follow, that its infledion muft be varied accordingly ; And therefore we may hence learn, upon what fure grounds aft the A- ftronomers hitherto have built, who have calculated the diftanee of the Planets from their Horizontal Parallax 3 for lince the RefraClion and Pa- rallax are lb nearly ally'd, that the one cannot be known without the other, efpecially by any wayes that have been yet attempted, how uncer- tain muft the Parallax be, when the Refradion is unknown? And how eafie is it for Aftronomers to aflign what diftance they pleale to the Planets,and defend them,when they have fuch a curious jubterfuge as that of Reffadi- on, wherein a very little variation will allow them liberty enough to place the Celeftial Bodies at what diftance they pleale. if
Ml
CROGR APH I'A.
If therefore we would come to any certainty in this fjoint, wc: jmufi; go other wayes to work , and as I have here examined the height and refra- d:ive property of the Air by other wayes then are ufual j fo mHft we find the Parallax of the Planets by wayes not y et pradifed ^ and to this end. I cannot imagine any better wayj then the Obfervations of them by two perlbns at very far diftant parts of the Earth, that lye as neer as may be under the fame Meridian, or Degree of longitude , but diifering as much in latitude, as there can be places conveniently found : Thefe t wo perfons, at certain appointed times, fiiould ( as near as could he ). ; both .at the fame time , obferve the way of the Moony Mar Venns^ Jnpiter^ and Saturn^ amongft the fixt Stars, with a good large Telefcope^ a^d ma- king little Iconifmcs, or pidures, of the fmall fixed Stars, that appear to each of them to lye in or near the way of the Center of ^he Planet, and the exafc meafure of the apparent Diameter 5 from the comparing of fuch Obfervations together, we might certainly know the true diftance, or Parallax, of the Planet. And having any one true Parallax of thefe Planets, we might very eafilyhave the other by their apparent Diame- ters/ which the likewife affords us very accurately. And thence
their motions might be much better known, and their Theories more ex- actly regulated. x^nd for this pur pofe I know not any one place more convenient for fuch an Obfervation to be made in, then in the Iflandof St. Helena^ upon the Coaft of Afxich^^ which lyes about fixteen degrees to the Southwards of the Line, and is very near, according to the latefl: Geographical Maps, in the fame Meridian with London ^ for though they may not perhaps lye exadlly in the fame, yet their Obfervations, being ordered according to what f fhall anon fhew, it will not be diffi- cult to find the true diftance of the Planet. But were they both under the fame Meridian^ it would be much better.
And becaufe Obfervations may be much eafier, and more accurately made with good Telejcopes^ then with any other Inftruments, it will not, Ifuppofe, feem impertinent to explain a little what wayes I judge moft fit and convenient for that particular. Such therefore as fhall be the Obfervators for this purpofe, fhould be furnifhed with the befl: Tclefiopef that can be had, the longer the better and more exaft will their Obler- vations be, though they are fomewhat the more difficultly manag’d* Thefe fhould be fitted with a Rete, or divided Scale, plac’d at fuch a di- fiance within the Eye-glafs,that they may be diftinftly feen,which fhould be the meafures of minutes and feconds, by this Inftrument each Ob- fervator fhould, at certain prefixt times, obferve the Moooj or other Planet, in, or very near, the Meridian 5 and bccaufe it may be very diffi- cult to find two convenient ftations that will happen to be juft under the fame Meridian, they fhall, each of them, obferve the way of the Planet, both for an hour before, and an hour after, it arrive at the Meridian 5 and by a line, or flroke, amongft the fmall fixed Stars^ they fhall denote out the way that each of them obferv’d the Center of the Planet to he mov’d in forthofe two hours : Thefe Obfervations each of them fhall repeat for many day es together, that both it may happen, that both o^
MiCRQGRAP H I A.
them mayfometimes make their Obfervations together, and that from divers Experiments we may be the better afTured of what certainty and exadtneis fuch kind of Obfervations are like to prove. And becaiife ma- ny of the Stars which may happen to come within the compafsof fuch an Iconifm^ or Map, may be filch as are only vifible through a good Tele- fcope^ whofe Pofitions perhaps have not been noted, nor their lOngrtudes, or latitudes, any where remarked^ therefore each Obfervator fhould in- deavour to infert Ibme fixt Star, whofe longitude, and latitude, is known 5 or with his Telefcope he (hall find the Pofition of fome notable tekjcopkal Star, inferred in his Map, to fbme known fixt Star, whofe place in the Zo- diAck. is well defin’d.
Having by this means found the true diftance of the Moon , and ha- ving obferved well the apparent Diameter oi it at that time with a good Tel^dpe, it is eafic enough, by one fingle Oblefvation of the apparent Diameter of the Moon with a good Glafs, to determine her diftances in any other part of her Orbit ^ or Dragon^ and confequentl y, fome few Obfervations will tell us, whether fhe be mov’d in an Ellip^s^ (which, by the way, may alfb be found, even now, though I think we are yet igntp* rant of her true diftance ) and next ( which without fuch Obfervati* ons, I think, we fhall not be fure of ) we may know exactly the bignefs of th^t E^ip It Sy or Circle, and her true velocity in each part, and thereby be much the better inabled to find out the true caufe of all her Motions. And though, even now alfb, we may, by fuch Obfervations in one ftati- On, as here at Londofty obferve the apparent Diameter and motion of the Moon in her Dragon y and confequently be inabled to make a better ghefs at the Species or kind of Curve, in which fhe is mov’d, that is, whether it be fphjcrical, or ellipticaly or neither, and with what propor* tional velocities fhe is carried in that Curve 5 yet till her true Parallax be known, we cannot determine either.
Next, for the true diftance of the Sun, the beft way will be, by accu* fate Obfervations, made in both thefe forementioned ftations, of fome convenient Eclipfe of the Sun , many of which may fo happen , as to be feen by both ^ for the Penumbra of the Moon may, if fhe be fixty Semi- diameters diftant from the Earth, and the Sun above feven thoufatrd, ex- tend to about feventy degrees on the Earth, and confequently bfefeeft by Oblervators as far diftant as Londony and St.Heknay which are not full fixty nine degrees diftant. And this would much more accurately, then any way that has been yetufed, determine the Parallax, and di- ftance, of the Sun, for as for the Hori2:ontal Parallax I have, already fhewn it fufficiently uncertain 5 nor is the way of finding it by the Eclipfo of the Moon any other then hypothetical 5 and that by the difference of the true and apparent quadrature of the Moon is left not uncertain, wit* ■eft their Dediudions from it,who have made ufe of it ^ for VendeMt puts that difference to be but 4'. 50“. whence he deduces a vaft diftance of theSun, as I have before fhewn. Ricciolot^i^kts it full 30'. 00. hntRek nolduSy and KircheVy no left then three degrees. And no wonder, for if we examine the we fhall fi$d it fo complicated with uncertain- ties. Firft,
MiCROGRAPHtAi
Firftj From the irregular furface of the Mooh^ and from feveral Paral- laxes, that iinlels the Dichotomy happen in the Nonage^mus of the Eclip- tich^^ and that in the Meridian, <&c. all which happen fo very feldom, that it is almoft impoffible to make them otherwile then uncertainly. Befides, we are not yet certain, but that there may be foriaewhat about the Moon analogm to the Air about the Earth, which may caufe a refra- ftion of the light of the Sun, and conlequently make a great difference in the apparent dichotomy of the Moon. 1 heir way indeed is very rational and ingenious^ and fuchasis much to be preferfd before the way by the Horizontal Parallax, could all the uncertainties be remov’d j and were the true diftance of the Moon known.
But becaufe we find by the Experiments of Vendilitie^ Reinoldus^ 8cc, that Obfervations of this kind are very uncertain alfo .• It were to be wifht, that fuch kind of Oblervations, made at two very diffant ftati- ons, were promoted. And it is fo much the more defirable, becaufe, from what 1 have now fhewn of the nature of the Air it is evident, that the refraftion may be very much greater then all the Aftronomers hitherto have imagined it : And confequently, that the diftance of the Moon, and other Planets , may be much lefle then what they have hitherto made it.
For fir ft, this Inflexion, I have here propounded, will allow the fha- dow of the Earth to be much fhorter then it can be made by the other Hypothecs of refraftion, and confequently, the Moon will not fufier an Eclipfe, unlefs it comes very much nearer the Earth then the Aftronomers hitherto have fuppofed it.
Secondly, There will not in this Hypothejis be any other fhadow of the Earth, fiich as Kepler fuppofes, and calls the Tenumbra^ which is the fha- dow of the refrafting Atmofphere 3 for the bending of the Rays being al- together caus’d by inflection^ as I have already fhewn , all that part which is aferibed by TCep/er, and others after him, to the or
dark part, which is without the /err /p, does clear vanifh 5 for in
t\{\siiypotheflsx\icvt\s no refracting furface of the Air, and confequently there can be no ftiadows, fuch as appear in the ninth Figure of the 37. Scheme^ where let ABC D reprefent the Earth, andEFGH the>^/- mojphere^wh. ich according to Keplers fuppofition,is like a Sph^ere of W ater terminated with an exaft furface EFGH, let the lines MF, LB, ID, K H, reprefent the Rays of the Sun 5 ’tis manifeft, that all the Rayes be- tween L B, and I D, will be reflected by the furface of the Earth BAD, and confequently, the conical fpace BOD would be dark and obfeure , but, fay the followers of Kepler^ the Rays between M F, and LB, and between I D, and KH, falling on the Atmojphere ^ are re- frafted, both at their ingrefs and egrefs out of the Atmoflhere^ nearer to^ wards the Axis of the fpaerical fhadow C O, and confequently, inlighten a great part of that former dark Cone, and fhorten, and contraCt, its top to N. And becaufe of this Reflection of thefe Rays, fay they, there is fuperinduc’d another fhell of a dark Cone F P H, whole Apex P is yet further diftant from the Earth : By this Femmbra^ fay they, the Moon
Micrographia.
is Edipfed, for it alvvayes paflcs between the lines i 2, and
To which I fay. That if the Air befuch, as I have newly fliewn it to be, and confequently caufe Inch an intiedion of the Rays that fall into it, thofe dark Venumbrds F Y Z H X VT , and O R P S, will all va- nifh. For if we fuppofe the Air indefinitely extended, and to be no where bounded with a determinate refradfing furface, as I have ihewn it uncapable of having, from the nature of it, it will follow, that the Moon will no where be totally obfeured, but when it is below the Apex N, of the dark blunt Cone of the Earth’s ihadow:Now,from the fuppofi- tion, that the Sun is diftant about feven thoufand Diameters, the point N, according to calculation, being not above twenty five terrefirial Se- midiameters from the Center of the Earth: It follows, that whenfoever the Moon eclipfed is totally darkned, without affording any kind of light, it muff be within twenty five Semidiameters of the Earth, and con- fequently much lower then any Aftronomers have hitherto put it.
This will feem much more confonant to the reft of the fccundary Pla- nets 3 for the higheft of Jupiter’s Moons is between twenty and thirty Jovial Semidiameters diftant from the Center of Jupiter 3 and the Moons of Saturn much about the fame numbci o{ Sat urni a I Semidiameters the Center of that Planet.
But thefe are but conjedures alfo,and muft be determin’d by fuch kind of Obfervations as I have newly mention’d.
Nor will it be difficult, by this Hypothejis^to^dXvt dWthe appearances of Eclipfes of the Moon, for in this Hypothejis alfo, there will be,on each fide of the fhadow of the Earth, a Venumbra^ not caus’d by theRefradi- on of the Air, as in the Hypothecs of Kepler 3 but by the faint inlight- ning of it by the Sun : For if, in the fixth Figure,we fuppofe ES Q_, and G S R,to be the Rays that terminate the fhadow from either fide of the Earth 3 E S coming from the upper limb of the Sun, and GSR from the under 3 it will follow, that the fhadow of the Earth, within thofe Rays, that is, the Cone G S E, will be totally dark. But the Sun being not a point, but a large area of light, there will be a fccondary dark Cone of fhadow E P G, which will be caus’d by the earth’s hindring part of the Rays ofthe Sun from falling on the parts G P R, and E P Q: of which halved fhadow, or Penumbra, that part will appear brighteft which lyes neareft the terminating Rayes G P, and E P, and thofe dar- ker that lye neareft to G S, and E S : when therefore the Moon ap- pears quite dark in the middle of the Eclipfe,fhe muft be below S,that is, between S and F 3 when fhe appears lighter near the middle of the Eclipfe, fhe muft pals fbme where between R Q_and S3 and when fhe is alike light through the whole Eclypfe, fhe muft pafs between RQ,, and P,
Obferw.
MiCROGRAPHiA,
241
Obferv. L I X. Of multitudes of fmall Stars dif cover able hj the Telefcope.
HAvingjin thelaft Obfervation, premis’d fornG particulars obfervable in the medium which we mufi look upon CceleflialOh]QScs^ I fhall here add one Obfcrvation of the Bodies themfelves j and for a Jpecimen I- have made choice of the Tleindes^ or feven Stars, commonly fo called C though in our time and Climate there appear no more then fix to the naked eye ) and this 1 did the rather, becaufe the defervedly fa- mous Galileo^ having publifht a Picture of this Ajierifme^ was ablej it feems, with his Glafs to difcover no more then thirty fix, whereas with a pretty good twelve foot Telefiope^by which I drew this 38 Icemfm^l could very plainly difcover feventy eight, placed in the order they are ranged in the Figure, and of as many differing Magnitudes as the JJierist^s^ wherewith they are Marked, do fpecifie , there being no lefs then four- teen feveral Magnitudes of thofe Stars, which are compris’d within the draught, the biggeft whereof is not accounted greater then one of the third Magnitude , and indeed that account is much too big,if it be com- pared with other Stars of the third Magnitude, efpecially by the help of a Telefcope 5 for then by it may be perceiv’d, that its fplendor, to the na- ked eye, may be fomewhat augmented by the three little Stars immedi- ately above it, which are nearadjoyning to it. The Telefcope alfo difco- vers a great variety, even in the bignelsof thole, commonly reckon’d, of the firft, lecond, third, fourth, fifth, and fixth Magnitude 5 lb that fhould they be diftinguifh’d thereby, thofe tix Magnitudes would, at leaft, af- ford no lels then thrice that number of Magnitudes, plainly enough dh ftinguifhable by their Magnitude, and brightnels ^ fo that a good twelve foot Glals would afford us no lels then twenty five feveral Magnitudes. Nor are thefe all, but a longer Glafs does yet further, both more nicely diftinguifh the Magnitudes of thole already noted, and allb difcover le- veral other of fmaller Magnitudes, not dilcernable by the twelve foot Glals ; Thus have I been able, with a good thirty fix foot Glals, to dilco- ver many more Stars in the Pleiades then are here delineated, and thole of three or four diftind Magnitudes lefs then any of thole fpots of the fourteenth Magnitude. And by the twinkling of divers other places of this Ajierijme^ when the Sky was very clear, I am apt to think, that with longer Glafles, or fuch as would bear a bigger aperture^ there might be difeovered multitudes of other Imall Stars, yet inconfpicuous. And irn deed, for the dilcovery of Imall Stars, the bigger the aperture be, the better adapted is the Glals 5 for though perhaps it does make the feveral %ecks more radiant, and glaring, yet by that means, uniting more Rays very near to one point, it docs make many of thofe radiant points confpi-
K k cuous,
Micrographia.
cuous, which, by putting on a lels aperture^ may be found to vanifii 3 and therefore, both for the difcovery of the fixt Star, and for finding the Satellites oi Jupiter, before it be out of the day, or twilight, lalwayes leave the Objeft-glafs as clear without any aperture as I can , and have thereby been able to difeover the Satellites a long while before ^ I was able to difeern them, when the fmaller apertures wtvQ put on 5 and ato~ ther times, to fee multitudes of other fmaller Stars, which a fmaller aper- ture makes to difappear.
In that notable Ajierifm alfb of the Sword of Orion, where the ingeni- ous Monfieur Hugens van Zulichemh^^ difeovered only three little Stars in a clufter, I have with a thirty fix foot Glafs,without any aperture (the breadth of the Glafs being about fome three inches and a half )difco vef d five, and the twinkling of divers others up and down in divers parts of that fmall milky Cloud.
So that tisnot unlikely, but that the meliorating of Telefiopes will af- ford as great a variety of new Difeoveries in the Heavens, as better yl/i- crofeopes would among fmall terreftrial Bodies, and both would give us infinite caufo, more and more to admire the omnipotence of the Crea- tor.
Obferv. LX. Of the Moon »
HAving a pretty large corner of the Plate for the (even Starrs, void, for the filling it up, I have added one fmall Specimen the ap- pearance of the parts of the Moon, by deferibing a fmall fpot of it, which, though taken notice of^ both by the Excellent Hevelius, and called Mons Olympus f though I think fomewhat improperly, being rather a vale) and reprefented by the Figure X,of the 38. Scheme, and alfoby the Learn’d Kicciolus, who calls it Hipparchus, and deferibes it by the Figure Y, yet how far fhort both of them come of the truth, may be fomewhat per- ceiv’d by the draught, which I have> here added of it, in the Figure Z, ( which I drew by a thirty foot Glafs, in oHoher 1664. juft before the Moon was half inlightned) but much better by the Reader’s diligently obforving it himfelf, at a convenient time, with a Glafs of that length, and much better yet with one of threefcore foot long ^ for through thefe it appears a very fpacious Vale, incompafled with a ridge of Hills, not very high in comparifon of many other in the Moon, nor yet very fteep. The Vale it folf A B C D, is much of the figure of a Pear, and from fo- veral appearances of it, feems to be fome very fruitful place, that is, to have its forface all covered over with fome kinds of vegetable fubftan- ees 5 for in all pofitions of the light on it, it feems to give a much fainter reflexion then the more barren tops of the incompaffing Hills, and thofe a much fainter then divers other cragged, chalky, or rocky Mountains of the Moon. So that I am not unapt to think, that the Vale may have
Vegetables
M I CR O GR A PH I A.
Vegetables analogus to our Grals, Shrubs, and Trees 3 and mofl: of thel6 incompaffing Hills may be covered with fo thin a vcgetaWe Coat, as we may obferve the Hills with us to be, fuch as the fliort Sheep paftuie which covers the Hills of Plains.
Up and down in feveral parts of this place here defcrib’d f astherh are multitudes in other places all over the furface of the Moon ) may be perceived feveral kinds of pits, which are fhap’d almofe like a dilh^ lome bigger, feme lels, fome ihallower, fome deeper, that is, they feem to be a hollow incompafled with a round rifing bank, as if
the febftance in the middle had been digg’d up, and thrown on either fide. Thefe feem to me to have been the effeds of feme motions within the body of the Moon, analogus to our Earthquakes, by the eruption of which, as it has thrown up a brim, or ridge,round about, higher then the Ambient forface of the Moon, fe has it left a hole, or depreffion, in the middle, proportionably lower 5 divers places refembling feme of thefe, I have obferv'd herein England^ on thetopsof fomeHills^ which might have been caus’d by feme Earthquake in the younger dayes of the world. But that which does mofi: incline me to this belief, is, firft, the generality and diverfity of the Magnitude of thefe pits all over the bo- dy of the Moon. Next, the two experimental wayes, by which I have made a reprefentation of them.
The firfi: was with a very feft and well temper’d mixture of Tobacco- pipe clay and Water, into which, if I let fall any heavy body, as a Bul- let, it would throw up the mixture round the place, which for a while would make a reprefentation, not unlike thefe of the Moon 3 but con- fidering the fiate and condition of the Moon, there feems not any proba- bility to imagine, that it Ihould proceed from any caufe analogus to this 3 for it would be difficult to imagine whence thofe bodies ihould come 3 and next, how the fubftance of the Moon Ihould be fo feft 3 but if a Bubble be blown under the furface of it, and (uffer’d to rife, and break 3 or if a Bullet, or other body, liink in it, be pull’d out from it, thefe de- parting bodies leave an impreflion on the forface of the mixture, exaftly like thefe of the Moon, lave that thefe alfo quickly fobfide and vanifo. But the fecond, and mofi: notable, reprefentation was, what I obferv’d in a pot of boy ling Alabafier, for there that powder being by the erupti- on of vapours reduc’d to a kind of fluid confifience,if,whil’ft itboyls, it be gently remov’d befides the fire , the Alabafier prefently ceafing to boyl, the whole forface, efpecially that where fome of the lafi Bubbles have rifen, will appear all over covered with fmall pits, exadfly fhap’d like thefe of the Moon, and by holding a lighted Candle in a large dark Room, in divers pofitions to this forface, you may exadly reprefent aU the rhsnomena of thefe pits in the Moon, according as they are raojrc or lefsinlightnedby theSun.
And that there may have been in the Moon fome foch motion as this, which may have made thefe pits, will feem the more probable, if we foppofe it like our Earth, for the Earthquakes here with us feem to proceed from fome foch caufe, as the boy ling of the pot of Ala-
K k 2 bafier.
£44 Micrographia.
bafter , there feeming to be generated in the Earth front feme fiibter- raneous^ hres^ or heat, great quantities of vapours, that is, of expan- ded aerial fijbftances, which not prefently finding a paflage through the ambient parts of the Earth, do, as they are increafed by therupplying and generating principles, and thereby ( having not fufficient room to expand themfelves ) extreamly condens’d , at laft overpower , with their properties, the refiftenceof the incompafling Earth, and
lifting it up, or cleaving it, andfo fhattering of the parts of the Earth above it, do at length, where they find the parts of the Earth above them more loofe, make their way upwards, and carrying a great part of the Earth before them, not only raife a fmall brim round about the place, out of which they break , but for the moft part confiderable high Hills and Mountains, and when they break from under the Sea, divers times, mountainous Iflands , this feems confirm'd by the Vulcans in feveral places of the Earth, the mouths of which, for the moft part, are incom- pafted with a Hill of a confiderable height, and the tops of thofe Hills, or Mountains, are ulually fhap'd very much like thefe pits, or dilhes, of the Moon .* Inftances of this we have in the deftriptions of jEtna in Si- cily^ of Becla in Iceland^ of T'enerif in the Canaries^ of the feveral F«/- ca»s in New-Spain^ delcrib’d by and more efpecially in the erupti-
on of late years in one of the Canary Illands. In all of which there is not only a confiderable high Hill raifed about the mouth of the Vulcan , but, like the fpots of the Moon, the top of thofe Hills are like a dilh, or ba- Ibn. And indeed, if one attentively confider the nature of the thing, one may find lufficient realbn to judge , that it cannot be otherwile ^ for thefe eruptions, whether of fire, orfmoak, alwayes rayfing great quan- tities of Earth before them, muft neceflarily, by the fall of thofe parts on either fide, raife very confiderable heaps.
Now, both from the figures of them , anjl from feveral other cir- cumftances^ thefe pits in the Moon feem to have been generated much after the fame manner that the holes inAlabafter, and the Vul- cans of the Earth are made. For firft, it is not improbable, but that the fubftance of the Moon may be very much like that of our Earth, that is, may confift of an earthy, fandy, or rocky fubftance, in feveral of its fuperficial parts, which parts being agitated, undermin’d, or heav’d up, by eruptions of vapours, may naturally be thrown into the feme kind of figured holes, as the fmall duft, or powder of Alabafter. Next, it is not improbable, but that there may be generated, within the body of the Moon, divers fuch kind of internal fires and heats, as may pro- duce fuch Exhalations , for fince we can plainly enough difeover with a Tekjeop^ , that there are multitudes of fuch kind of eruptions in the body of the Sun it felf, which is accounted the moft noble iEtherial bo- dy 3 certainly we need not be much feandaliz’d at fuch kind of altera- tions, or corruptions, in the body of this lower and left confiderable part of the univerfe, the Moon, which is only fecundary, or attendant, on the bigger, and more confiderable body of the Earth. Thirdly, ’tis not unlikely, but that fuppofing fuch a fandy or mouldring fubftance to
M I C R OG R A PH 1 A.
be there found, and fuppofing alfo a poffibility of the generation of the intemal elapical body (whether you will call it air or vapours) ’tis not unlikely. I fay, but that there is in the Moon a principle of gravita- tk)B, ftich as in the Earth. And to make this probable, I think, we need no better Argument, then the foundnels, or globular Figure of the bo- dy of the Moon itfelf, which we may perceive very plainly by the 5>- lefcope^ to be ( bating the Imall inequality of the Hills and Vales in it, which are all of them likcwile lhap’d, or levelled, as it were, to ahfwef to the center of the Moons body ) perfectly of a Sphaerical figure, that is, all the parts of it are fo rang'd (bating the'comparitively friiall rug- gednefs of the Hills and Dales ) that the outmoft bounds of them are equally diftant from the Center of the Moon, and confequently, it ii exceedingly probable alfo, that they are equidiftant from the Center of gravitation , and indeed, the figure of the fuperficial parts of the Moon are fb exactly fhap’d, according as they fliould be, fuppofing it had a gravitating principle as the Earth has, that even the figure of thofe parts themfelvesisof fufficient efficacy to make the gravitation, and the other two fLippofitions prebable ; fb that the other ffippofitions may be rather prov’d by this confiderable Circumftance, or Obfervation, then this flippos’d Explication can by them 5 for he that fhall attentively obfervewith an excellent how all the Gircumftances, notable in
the ftape of the fuperficial parts, are, as it were, exaftly adapted to luit with fuch a principle,will,if he well confiders the ufual method ofNa- ture in its other proceedings,find abundant argument to believe it to have really there alfo fuch a principle5 for I could never obferve,among all the mountainous or prominent parts of the Moon ( whereof there is a huge variety ) that any one part of it was plac’d in fuch a manner,that if there fhould be a gravitating, or attracting principle in the body of the Moon, it would make that part to fall, or be mov'd out of its vifible pofture. Next, the fhape and pofition of the parts is fuch, that they all feem put into thofe very fhapes they are in by a gravitating power .* For firfl:,there are but very few clifts, or very fteep declivities in the afcent of thefe Mount^ains ^ for befides thofe Mountains, which are by Hevelins call’d thef Apennine Mountains, and fome other, which fecm to border on the Seas of the Moon, and thofe only upon one fide, as is common alfb in thole Hills that are here on the Earth ^ there are very few that feem to have very fteep afcents, but, for the moft part, they are made very round, and much refemble the make of the Hills and Mountains alfo of the Earth ^ this may be partly perceived by the Hills incompaffing this Vale, which I have here defcrib’d 5 and as on the Earth alfb, the middlemoft of thefe Hills Teems the higheft, fo is it obvious alfb, through a good Te- lejcope^ in thofe of the Moon 5 the Vales alfb in many arc much fhap’d like thofe of the Earth, and I am apt to think, that could we look upon the Earth from the Moon, with a good Telejcope^ we might eafily enough perceive its furface to be very much like that of the Moon.
Now whereas in this fmall draught, (as there would be multitudes if the whole Moon were drawn after this manner) there are feveral little
EbvjllitionS;,.
Ml CROC RAP HI A.
Ebullitions, orDifhes, even in the Vales themfelvesjand in the incompaf- (ing Kills alfo ^ this will, from this fuppofition, (“which I have, I think, up- on very good reafon taken ) be exceeding eafily explicable 5 for, as I have feveral times allb oblerv’d, in the furfacc of Alabafter lb ordered, as I before deferib’d, fo may the later eruptions of vapours be even in the middle, or on the edges of the former , and other fucceeding thefe allb in time may be in the middle or edges of thefe, of which there are inftances enough in diveps parts of the body of the Moon, and by a boyling pot of Alabafter will be fufficiently exemplifi’d.
To conclude therefore, it being very probable, that the Moon has a principle of gravitation , it affords an excellent diftinguilhinginftance in the fearch after the caufe of gravitation, or attraftion, to hint, that it does not depend upon the diurnal or turbinated motion of the Earth, as Ibme have Ibmewhat inconfiderately fuppoled and affirmed it to do 5 for if the Moon has an attraftive principle, whereby it is not only ftiap’d round , but does firmly contain and hold all its parts united, thftugh many of them feem as loole as the land on the Earth, and that the Moon is not mov’d about its Center , then certainly the turbination cannot be the caufe of the attraction of the Earth , and therefore Ibme other principle muft be thought of, that will agree with all the lecundary as well as primary Planets. But this, I confels, is but a probability, and not a demonftration, which (from any Oblervation yet made J it leems hardly capable of, though how fuccelsful future indeavours (promoted by th® meliorating of Glaftes, and oblerving particular circumftances) may be in this, or any other, kind, muft be with patience exped:ed.
FINIS.
<4» ■c-y* cy» -cy» *-y» «$> <4^ v-j«» «y» t<y> «y» «<p* «ya eg* e^ <4‘* ■‘tf*
THE TABLE-
Pag.
I Obfervat. i . Of the point of a Nee- dle.
ADefcription of it : what other Bodies have the Jharpeji points : of the ruggednefs of polift Metal, A g defcription of a printed point. Of ve- ry fmall writings and the ufeof it for fkret intelligence : the canfi of the courfnef of printed lines and points^
^ Obferv.2. Of the Edge of a Razor.
A defcription of it : the canfes of ^ its roughnef : of theroughnef of very well polifjt Optdk. GlaJJes.
Obfer.3. Of fine Lawn.
A defcription of it : A flkgn Flax mention d^an attempt to explicate the 6 - Phaenoraena of it , with a conje&ure at the caufe of theglofof Sil^
Obferv. 4.,^ Of Tabby.
A fwrt defcription of it. A conje- 7 Unre about the reafon why Silk^ is Jb fufceptible of vivid colours : and why Flax and Hair is not. A conjecture ^ that it may perhaps be pojfible to Jjin a kind of artificial Silk^ out of fime glutinous fubjiance that may equalise natural Bilk.
% Obferv. 5. Of water’d Silks.
7he great unaccuratenefi of artifi- cial works. A defcription of apiece of ^ water d Sd/ij an Explication of the caufe of the Phaenomena .* the way by which that operation is perf ?rm’d :
fome other Phsenomena mention d 10 depending on the fame caufe.
Obferv. 6. Of Glafs-Canes.
The exceeding fmalnefi of fome of thefe Bodies. By what means the hoi- lownefi of thefe final! pipes was difco- verd: fev eral Vhdenomtnz of it men- 1 1 tiond. An attempt fo explicate them from the congruity and incongruity of 12 Bodies: what thofeproprieties are. A hypothetical explication of fluidity : of the fluidity of the airland fever al other 1 4 Phsenomena of it : of congruity ^ in- 1 5 congruity^, illufirated with fiver al Ex- 1 6 perimentscwhat efifeBs may be afirib'd 1 7 to thefi properties : an explication of iS the roundnef^ of the furface of fluid Bodies ; how the ingrefi of fluid bodies 1 9 into a fmall hole of an heterogenious 20 body is hindred by incongruity.^ a multitude of Phaenomena explicable 2 1 hereby. Several ^uieries propounded j I. Concerning the propagation of light through differing mediums. 2. Con- ‘22 cerning Gravity. 3. Concerning the roundnefi of the Sun^ Moon^ and T la- nets. 4. Concerning the roundnefi of Fruit Sj Stones^ and divers artificial Bodies. His HighnefiFrinceKw^exts 23 way of makfng shot. Of the roundnefi 24 of Hail. Of the grain of Kettering Stone^and of the Sparky of fire. ’y.Con- 2 5 cerning fpringinefi and tenacity.
6. Concerning the original of Foun- 26 tains 5 fiver al Hifiories and Experi- ments relating thereto. j. Concerning 27 the diffolution of Bodies in Liquors.
8. Concerningthe univerfality of this 28 Principle : what method ivas taken in making and applying experiments. The
explication
1 he 1 A B L E.
explication of fltration^ and fiver a I
29 other Ph^enomena jjueh as the motion of Bodies on the Jurface of Liquor fe-
30 veral Experiments mention d to this purpofi.Of the height to which the wa- ter may rife in thefi Tipes-^and a conje-
3 1 Bure about the juices of Vegetables the ufi of their pores. A further expli- cation of Congruity:And an attempt of folving the Phsenomena of the Jirange Experiment of the fufpenfion of the
32 Mercury at a much greater height then thirty inches. The efficacy of im- mediate contaB^ and the reafin of it.
53 Obferv. 7. Of Glals drops.
Several Experiments made with
34 thefi final/ Bodies. The manner of the breaking and pawing of them^ expli-
55 cated by Figures. What other bodies will befiawed much in the fame man- ner : fome other tryals^ and a defcrip- tion of the Drops themfilves : fome conJeBures at the eaufi of the Phse- nomenn Jndeavoured to be made pro-
5 6 bable by fiver al Arguments and Expe- riments.An Experiment of the expan- Jton of Water by heat^and fiirinking by cold .* the like Proprieties Juppos'd in
3 7 Glaf drops , and what effeBs proceed from them : the fiven Propofitions on which the conjeBures are grounded. Experiments to Jhew^ that bodies ex-
38 pand by heat. The manner of making Thermometers , and the Inflrument
39 for graduating them. The manner of graduating them^ and their ufi : 0- ther Experiments to prove the expan-
40 fion of bodies by heat. Four experimen-
tal Arguments to prove the expanfien of Glafi by heat : further provd by the Experiment of boy ling Alabajier 5 which is explicated. An explication of the contraBing of heated Glafnp-
^2 on cooling. An explication hew the parts of the Glafi become bent by jud- den cold^ and how kept from extrica-
ting themfilves by the contignation of the Glafi drop 5 which is further ex- plicated by another Experiment made with a hollow Glafi ball; the reafin of^^ the flying afunder of the parts further explicated : that tk probable thefi bo- dies may have many flaws, though not vijible,and why : how a gradud heat- ing and cooling does put the parts of 44 Glaf, and other hardned bodies , into a loofir texture.
Obferv. 8. Of Fiery Sparks.
The occafion and manner of ma- king this Experiment : divers Obfir- vations fit down in order to the find- ing out thereafons : fome conjeBures concerning it, which are endeavoured to be explicated and confirm'd by fe- ver al Experiments and Reafins : the Hypothefis a little further explica- ted. Some Obfirvations about the Globular Figure ; and an Experiment of reducingthe filings of Tin or Lead to exaBly round Globules.
45
46
47
Obferv, 9. Of Fantaftical Colours.
The texture of M\\(co\y Glafi', its Figures:what other Bodies are likg it: . g that it exhibits fiver al colours , and ^ how:feveral Obfirvations and Experi- ments about thefi colours : the reafin why on this occafion the nature of c§- lours is inquir'd into. A conjeBure at the reafin of thefi colours explicated 5*^ by fiver al Experiments and Reafins : Firfi, by continual cleaving the Body till it bjecome colbur d. Secondly, by producing all k/uds of colours with two flat Plates of Clafl. Thirdly, by blowing Gla^ fo thin in the Lamp, till it produce the fame efleB. Fourthly, by ^ doing the fame with Bubbles of di- vers other tranjparent Bodies: the reafins of the colours on nealed Steel, where by the way the caujes of the 5^
kardning
The Table,
52 hardning and tempering of Steef | endeavour’d to be fewn and expljca- j ted by feveral Reafons and Experi- ments: the reafonof the colours on 55 Lead^BrafjCopperj Silver^Sic. other Injianoes of fuch colour’d bodies in animal fubfiances : feveral ether di- JiinguiJlding Obfervations. Des Cartes
54 Hypothefis of Colours examin’d. An Hypothefis for the explicat7on of light by motion.^ indeavoured to be explicated and determined by feve-
55 ral Reafons and Experiments : three dijiinguijhing Properties of the moti- on of hght. 1 he drfirjguifnng Proper -
^ ties of a trafparent Medium that there feems to be no Experiment that proves the Infantaneous motion of g-j light "] the manner of the propagati- on of light through them. Of the ho- mogeniety and heterogeniety of tranjparent Mediums , and what ef- feBs they caufe on the Rayes of light ^ explicated by a Figure: an Exami- nation of therefraBion of the Rays by a plain Surface ^ which caufes Co- lours. An Examination of the like ef- < g feBs produced by a Jpherical Surface :
^ the ufe that may be made of thefe Ex- periments 5 for the examination of feveral Hypothefes of Colours. Des
60 Cartes Hypothefis examin’d. Some
61 Difdculties taken notice of in it. What feems mofl likely to be the caufe of co- lour: that propriety is indeavoured
92 to be Jhewn in a Glaf ball : that the refleBion is not necejjary to produce
63 Colours nor a double reJraBion : the Hypothefis^^r^^er examined, both in
64 the pellucid Medium and in the Eye. The definitions of Colour s'-^and afur-
65 ther explication and examination of
66 the Proprieties of laminated Bodies ;
67 by what means they conduce to the produBion of Colours.
Obferv. 10. Of Metalline Colours.
68 ’ibhat all Colours feem to be caus'd by
refraBion. An Hypothefis confonant hereunto,explicated by Figures. How 69 feveral Experiments , of the Judden changing of Colours by Chymical Li- quors, may be hereby explicated : how 70 many wayes fuch Chymical Liquors may alter the colours of Bodies. ObjeBions made againfi this Hypo- Jt thefis of two colours only, indeavour- ed to be anjwerd, by feveral Reafons and Experiments. The reajbn why 7^ Jbme Colours are capable of being di- luted, others not : what thofe are: that probably theparticles of moji metal- line Colours are tranjparent 5 for this feveral Arguments and Obfervations are recited : how Colours become in- 73 capable of diluting, explicated by a S imilitude. An Infirument, by which 74 one and the fanie coloured Liquor at once exhibited all the degrees of co- lours between the paleji yellow and deepeji red : as likewife another that exhibited all varieties of blues : fe- veral Experiments try’d ivith thefe Boxes. An ObjeBion drawn from the nature of Painters colours anfwered: that diluting and whitening a colour are different operations 5 as are deepening and blackening : why Come may be diluted by grinding, andfome other by being tempered withOyl: feveral Experiments for the explica- 76 ting of feme former Afiertions : why 77 Painters are forced to makg ufe of many colours : what thofe colours are : and how mixt. The conclufion, that 78 mofl coloured Bodies feem to confifi of tranjparent particles : thatallco- 79 lours dijjbluble in Liquors are capa- ble of diluting : fme of mixing, what a firange variety may thereby be pro- duc’d.
Obferv. ii. Of the Figures of ^ Sand,
Of the jubfiunces and fi:apes of §0 L 1 common
The Table.
common and other Sands : a defers- ption of a very fmali shell.
8i Obferv. 12. Of Gravel in Urine.
A defeription of ftch Grave f and 8 2 feme tryals made with it , and conje- &nrcs at its catfe.
Obfer. 15. Of Diamonds in Flints.
A defeription and examination of fame of them , explicated further by Cornif j Diamonds : fiver al Obfirva- tions about refc&ion and refra&ion : and feme deductions therefrom 5 Oi an explication of whitenejs’j that the Air has a fir onger reflection thenWa- ter. Hotp fiver al Bodies may be made tranfparent : an explication of the 85 PhcEnomena <?/OcLilus Mimdi. Of the regular Geometrical Figures of fever al Bodies : an hypothetic alexpli-
87 cation snentioned: the method of pro- ficuting this inquiry.
88 Obferv 14. Of frozen Figiir e.
Fhe Figures of hoar Frofi^ and the 8^ Vortices on windows : fiveral Obfir- vations on the branched Figures of 'Orine : the Figures <^'Regulus Mar- tisfrellatus, and of Fern. OftheFi- C)2 of Snow. Of frozen water.
Obferv. 15. Of Kettering Stone.
A defeription of the Figure of the V articles^ and of the Pores^ and of the Contexture, Several Obfervations and Confiderations thereupon: fome Con- jectures abotit the medium and pro- 97 pstgation of lights and the confiitution of fluid and tranfparent Bodies, Se- ^8 veral Experiments to prove the po- roufne^ of \Marble , and fome other Stones. An account of fome Experi- ments to this purpofe made on an
Ociilus Mundi : feme other Confide- 99 rations and Experiments about the poroufnefi of Bodies: fosns other Con- joo federations about the propagation of light and refraCtion,
Obferv. 16. Of Charcoal.
Of two fort of Pores to be found jqi in all Woods and Vegetables',^ the fi)ape of them ^ the number , thie fi^ nef manner and ufi of thefe Pores.
An explication of the Phsenomena 102 of Coals. The manner of charring Wood^ or any other body. What part of Wood is combufiible. An Hypo- jo-> thefis of fire explicated in twelve particulars wherein the A&ionof the Air^ as a Menftruum; in the dif fiolution of all fulphureom bodies^ is very particularly explicated^ and 105 fome other Confederations about the Air propofid: the examination of a piece of Lignum foffile fint from Rome,' and feme Con cl ufi on s thence deduc d.
Obferv. 17. Of Wood, and other 107 Bodies, petrified.
Several Obfervations of divers finds of thefe fubfiances.A more par- 1 08 ticular examination and explicatfi on of one very notable piece of petri- fied Wood 3 and fome Conjectures a- bout the caufe of thofe productions fever a I Obfervations made on other.j^^g petrified Bodies^ as Shells.^ See. And j j q feme probable Conclufions thence de-\ j j j clucd^ about the original caufe of 112 thofe Bodies. ^
'■ - .T •
Obferv. 18. Of the Pores of Cork, and other Bodies. ■
Several Obfervations and Confe- derations about the nature of Corfi: * the number of Pores in a cubical
Inchj
The Table.
Inch^ and feveralCoujiderations a-
1 1 5 boiit Pores. Several Experiments and Obfervations about the nature of Cork^: the Texture and Pores of the Pith of an Elder ^ and fever al o- ther Trees : of the Stall{s of Bur- doc^preafels^DaiJiesf arret fennel^
116 Ferne^Reeds^^c. of the frothy tex- ture of the Pith of a Feather : fome Conje&ures about the probability of values in thefe Pores. Argued alfo from the Phenomena of the fenf-
1 1 7 ble and humble Plant : fome Obfer^
120 vations on which are inf r ted,
12 1 Obferv. 19. Of a Vegetable
growing on blighted Leaves.
122 Several Obfervations and Exa-
123 mi nations made of them: fever al 121^ Conf derations about fontaneous 12^) generation arifing from the putre-
faClion of Bodies.
Obferv. 20. Of Blew Mould and Mulhromes.
126 The defeription of fever al kjnds 12 j of Moulds. The method of proceed- ing in natural Inquiries. Several Conf derations about the nature of Mould and Mufromes. i. That they may be produc d without feed.
2. That they fern to have none.
3. That Saltsf^c. are Jhap' d into as j28 curious figures without a feed. i^.Of
a hind of Mufijrome growing in a Candle: A more particular explica- tion of this laf frt of Mufijromes. 1295* ^f figuce and manner of the produSlion of petrified Iceiclesfeve- ral deduBionsfrom thefe Confidera-
1 30 about the nature of the vege- tation of Mould and Mufhromes.
13 1 Oblerv. 21. Of Mols.
1^2 defeription of fever al forts of
MoJJes upon this occafion fiver al Conje&ures^about the manner of the produBion of thefe kinds of Bodies^ are hinted^ and fome of them expli- cated by a Similitude taken from 4^33 piece of Clock-work- Thevaji diffe- 10 a rence of the bignefiof vegetable Bo- ^ dies 5 and the probability that the leaf may comprehend as curious contrivances as thegreateft. Ofmul- 1 2 e titudes of other Moulds ^Mojfis^and Mufiirom-es , and other vegetating Principles, in Water, Wood, Sec. ■
Obferv. 22. Of Sponges, and other fibrous Bodies.
Several Obfervations andConje- cl nr es about the making of thefe Ba- dies andfiveral Hifi cries out of Authors. Scarce any other Body hath 137 fitch a texture--) the fibrous texture of Leather, Spunky, Sec. (which are 139 there defi:rib d ^ come nearefi to it.
That upon tryal with a piece of Spunge and by I the necejfity of re- 140 §iration could not be alter d. ^
Obferv. 23. Of the Form of Sea- weed.
From the enrioufiy fijapd Sur- face of this Sea-weed, and fome 0- t hers, is conjeBured the pojfibility <?/ 1 4 1 multitudes of the like.
Oblerv. 24. Of the Surfaces of Ibme Leaves.
The defeription, i. Of the bald Surfaces of Leaves. 2. Of the dow- ny Surfaces of fiveral others.
3. Of the gummous. exjudation, or final/ tranfiarent Pearls, difeovered with . a Microfeope in fiveral 0- thers. An Infiance of all which is ajf irded in a Rofimary Leaf
Oblerv,
The Table.
Obferv. 31. Of Ptirllane Seeds.
Obfcrv. 25. Of the ftinging Points of a Nettle.
A defcription of the Needles and feveral ether contrivances in the leaf S44 of a Nettle : how the flinging pain Is created : upon this feveral confdera- tions about poyfomng Darts are fet down. An Experiment of kflling Effs, and Fifhes with S alt, SomeconjeUures at the efficacy of Baths ^ the ufe that may be made of injeUing into the 145 Veins. Avery remarkable Hiflory out of Bellonius 5 and fame Confide- rations about (laining and dying of Bodies,
Obferv. 26. Qf Cowage.
The de/cription of it out e/Parkin- 1 4<^ ibn/tf « Experiment made of it : a de~ fcriptioUy and feme conjeUures at the caufeof Phsenomena.
Obferv. 27. Of the Beard of a wild Oat.
147
148 defcription of its Jhape and
1 49 properties : the manner of making a
150 Hygrofcope 5 and a Conje-
Uure at the caujes of thefe motions^
IJ2 and of the motions of the Bdufcles.
Obferv. 28. Of the Seeds of Ve<> nice Looking>glafs.
1 5-5 Ehe defcription of them, '
Obfer.29. Ofthe Seeds of Time, i
r54 A defcription of them. A digreffton about Natures method,
Obferv. 30. Of Poppy Seeds.
ipS The defcription and ufe of
them.
A defcription of thefe and many other Seeds.
Obferv. 32. Of Hair.
157
The defcription of feveral forts ^ i j8 Hair j their Figures and Textures : the reafen of their colours, A defcripti^ on of the texture of theslqn^ and of i^q Spunk and Sponges : by what paf- kjj fages and pores of the sfin tranlpira- tion feems to be made Experiments to prove the poroufnefs of the skin of Vegetables.
Obferv. 33. Of the Scales of a 1^2 Soale.
A defcription of their beauteous form.
Obferv. 3 4. Of the Sting of a Bee. j
A defcription of its Jhape ^ mecha: nifme, and ufe.
Obferv. 35. Of Feathers,
166
A defcription of the Jhape and cu- rious contexture of Feathers : and feme conjeUures thereupon.
Obfer . 3 ^ . Of Peacocks Feathers.
A defcription of their curious form 1 g 8 and proprieties I with a conjeSlure at 169 the caufe of their variable colours.
Obfer. 37. Of the Feet of FlyeS;^ and other In-fedfs.
A defcription of their figure, parts, and ufe:, and feme confiderations thereupon^
Obferv.
The Tab tiE .
17a Obrer.38. Of the Wings of Flycs.
jifter what manner ^and hew fivift- 173^ the wing! of InJeBs rhov'e. A de- fcription of the Pendulums under the 174 Wtdgs ^ and their motioh :' the fhape and JiruBure of the parts of the wing.
- i
I77 Obfer. J9. Of the Head of a Fly,
I. AH the face of a Drone-fly is no- thing almofl but eyes. 2. Tbofe are ^7^ of two magnitudes. %. They are Bemifpheres, and very refle&tve and fmooth. /^.Some direUed towards eve'-> ry quarter. 5 . Horo the Fly cleanfes them.6 Their number, y. Their order ;
177 divers particulars ohflervd in the dif
178 feUing ahead. That the fe are very probably the eyes of the Creature 5 ar» ghed from feveral Obfervations and
179 Experiments, that Crabs ^ Lobflers,- Shrimps ^feem to be water lnfeUs,and to be framed much like Air InfeHs'.-
1 80 Several C on fi derations about their mamer of vifion.
Obfer.40.Of thcTeeth of a Snail. iSi A brief defcriptionof it.
grejfive land transformation. A Bido- l8p
':ed out of about the j §3 variotcs wayes of the generations of Infers : by what means they aCl x gg feemingly wifely and prudently: Seve-- ^ qq ral §luceries propounded. Toflfcript, j ^ ^ containing a relation of another very j^2, odd way of the generation of Inf eBs.
A n ObferVation about the fertility of the Earth of our Climate m producing InfeSts,' aiid of divers other wayes of 19 ^ their generationy
Obferv* 44. Of the tufted Gnat.
Several Obfervables about InfeUs, and a more particular de fcription of 194 the parts of this Gnat.
Ob. 4$. Of the great belly’d Gnat, j ^ ^
A Jhort de fcription of it.,
Obfer. 4<J, Of a white Moth.
A de fcription of the feathers: and wings of this, and feveral other In- feBs. Divers Conf derations about the g
wings, and the flying of InfeBs and Birds.
ry fomewhat AnaloguS a Pifo. Several Obfervations
Obfer V. 41. Of the Eggs of Silk- worms.
I §2 Several Obfervables about the
Eggs of JnfeBs:
183 Obferv. 42. Of a blue Fly.
184 A de fcription of its outward and inward parts. Its hardinefs toindure
l8y free^ng^and fteeping inSpirit of wine.
Obferv. 45. Of a water Infedf.
18^ A de fcription of its Jhape, tranfpa-
rencji motion^ both internal and pro-
Obf. 47. Of the Shepherd Spider.
A defcription of its Eyes : and the foe bets of its long legs: andaConje- 199 Bure of the mechanical reafon of its , s. fabriek, j together with a fuppoftion^ that ’tis not unlikely fut Spiders may have the make of their inward parts exaBly like d Crab, which may be caU'd a water Spider. <:
Obfer.48. Of the hunting Spider.
A Jhort defcription of it s to which is annexe an excellent Hi (lory of it^ made by Mr „UyQ\jn. . Some further M m Obfer-^
The Table.
2O2 OhfervatioHs on other Spiders , and their Webs , together with an exami- nation of a white S uhflame flying up and down in the Air after a Fog,
205 Obfer. 49. Of an Ant.
That all [mail Bodies, both Vege- table and Animaf do quickly dry and wither. The bejl remedy I found to hin- der it^and to make the Animal lye fill
204 to be obferv'd. Several particulars re- lated of theaUionsof this Creature
2©f and a flsort defer iption of its parts.
Obf. 50. Of the wandring Mite.
206 A defcriptioH of this Creature^ and of another very [mail one , which ufu-
207 company. A ConjeHure at the original of Mites.
Obfcrv.51. OfaCrablike Infed,
30 8 A brief defer iption of it.
Obferv. 52. Of a Book-worm.
3O9 AAefeription of it 5 where by the way is inferted. a digreffion^ experi- mentally explicating the Phsenome-
210 ViZ of Pearl. A confideration of its
digefive faculty.
Obferv. 53. Of a Flea»
211 A fhort defcription of it.
obferv. 54. Of aLoufe.
a 1 2 A defcription of its parts ^and fome
213 notable circumfances.
Obferv. 55*. Of Mites.
The exceeding fmalnef of fome 'Mites ^and their Eggs. A defcription
2140/ the Mites of Cbeefe : and an inti-
mation of the variety of forms in other Blites^ with a ConjePiure attbe team 2r f fon.
Ob,^f5. Of fmallVincr Mites.-'
A defcriptionof them aghef at their original their exceeding fmal- nef s compared with that of a Wood- loufe^from which they may be fuppes*d to come.
Obferv. 57. Of Vinegar-worms.
A defcription of them , with foms 217 confi derations on their motions.
Obf. 58. Ofthe Inflc(5tion ofthe Rays of Light in the Air.
A f sort rehear fal of fever alPhi^- 218 nomena. An attempt to explicate 219 them-.the fuppojttion founded on two Prepoftions , both which are indea- voured to be made out by f ever al Ex- periments. What denfity and rarity is in reffebi ofrefraUion: the refrabli- on of Spirit of Wine compared veitb that of common Water : the refraUton of Ice. A n Experiment of mahfng an Undulation of the Pays by the mixing j of Liquors of differing denfty. The cxplicationof infled:ion, mechanic* cally and hypothetically : what Bodies have fuch an inflexion. Several Ex- periments to Jhew that the Aiflhas F ' this propriety that it proceeds from the differing denfty of the Air : that the tipper and under part of the Air ^ 5 - are of differingdenfty -. fome Expert- ments to prove this. A Table of the ~
firength of the fpring of the Air , anx fwering to each degree of extenfion\ - when firji made , and when repeated. 224 Another Experiment of comprejfing 225 the Air. A T able of the firength of the 2 2S Air 5 an fwering to each comprejfton and expanfion j from which the height
of
The Table.
22.7 fuppos'd inde finite i
22% to rphat degree the Air is rarifidat any dijiance above the Surface of the Earth : horv, from this, Infiehiion is inferr'ds and Phsenoraena
explain’d. That the Air near the Earth is compos’d of parts of differing j denfity-i made probable by jeveral 22 Experiments and Obfervations ; hew ^ this propriety produces the effeBs of the waving and dancing of Bodies i <A, and of the twilling of the. Stars, ipgy^everal -Phxnotnena explicated. Some ^uceries added.
1 . Whether this Principle may not be made ufe of, for perfeBing Optick.
234 Glaffes f what might be hoped from it if it were to be done f
2. whether from this Pr^^eiph the apparition of fome new Stars mdjf not be explicated f
. . 3 . whether the height of the ’ A ir may be defin'd by it f ' . ,
. 4. whether time may ml fotne-
'.ff {times be fo great a difparity pf den^
• ■ ' fity between the upper and under farts '''^'""bfithe Air ^ ns ta make a refitBiiig Surface f ‘ "
201- T‘ whether t if fo, this will not ex- plicate the Phsenomena of the Clouds. An Experiment to this pur- pofe f
2j6 7‘ d{ayes from the
' top of Mountains are not bended into ■ Curve-lines by infieUion f An Argu- ment for it, taken from an Experiment madeonSt.VdxA's Steeple.
8. whether the dijiance of the Planets will not be more difficult to ^17 be founds What wayes are mojl like- ly to reBifie the difiance of the Moon : the way of fitting Telefcopes for fucb obfervations. How to make the 2 ^Obfervations^ andhow from them to ^ find the true difiance of thct Moon at any time. How the dijiance of the Sun may be found by two Obfervators.The 7 39 Jjy f.f)g Dicotoms of the Moon un-
certain. That the dijiance of the Moon may be lefs then it has been hitherto fuppes’d. Kepler’j Suppofiti- on not fo probable: the explication of 240 the Phsenomena another thefis*
Obferv. 59* Of the fixt Stars*
241
C'-.>
O
a
Of the multitudes of Stars difco- verable by theTcdcico^t ^ and the variety of their magnitude si 7^. Stars dfimgujjbt inlhe. Pleiades:^^^^ there . are djgreks.offb^teff^ep m theStarJ accounted of the fame magnitude ; the longer the Glafies are, and the bigger apertures they will indure , the more fit they are for thefe difeoveries : that 'tis probable, longer Clajfes would yet makegr^ato^ difeoveries. 5. Stars difcoverdinthe Galaxie of Orion’/ b" word.
ObferV. ^oTOf&.Mbon.. ‘
■ . U { dffirjptioh. off^a^Vale in the' Moon i^-what call d and {^ ^icCi6Tii‘'Sj«w^ how defer ih’dhy them: withwhi^t fuhjlanc/Sy tlpe Mils of the ^ Moonmtiy'be'€ovei'd. A defeription of the pits of the Moon , and a conje- Bure at their caufe ; two Experiments that make it probable, that of the fur: face of boy Pd Alabajler dufl feeming 2^^ the mo fi likely to be refemhledhy eru- ptions of vapours out of the body of the Mom : -Earthquakes jeem to be '
generated much the fame way," arid their effeBs feem very fimilar.An Ar^. gument that there may be fucb vari^~ tions in the Moon , beeauje greater have been obferv’d in the Sun.becaufe the fuhjlance of the Moon and Earth feem much alipe : and becdufe ’tis pro- bable the Moon has a gravitating principle : this is argued from feveral particulars. The reafon why fever al pits are one within another. The ufe ‘ that may be made of this Inffance of a gravity in the SUtgin.
EHRATA.
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01
IN the Preface, Page 7. line 18. read fiet^^ line 14. read Gilhert, Harvy.
PageiJ.Iineult. readrt^e }\>.i^Xii.x.fmall lens :l. penult, t, that proceeds from : p.^o.l. ^^.t.vhenyoH: p.48.1.34.r.,troa(fe/l;.p»J7.1» J9.de!etwpi^x. I.f4. r. water-drop : p.d4. If.r.duSiott of G ^ c H : I-J^.r. im- prefsions:pi96X^l.t.tompofe: p.ioo.l.li. t.Merfennus: p.\o6h%.t.extteamly : p. no 1 S.r.4;f : l.tz, t.thofe ; p.Ht.l.it.r..A4dronindus,wormius : p.izi.I.^.dclc of: dt\e fromtp.ii^.l.xS.i. fifth place ;
f .1^0,1.19. 1. Serial menft/UHm ‘P- ^i^-l‘‘i9-r. knew how : p.l44>I.t.r. partsef the: p. I47,1.5<. r. /eo^’dow; p, l^i. I.i J.r, 6®iy ; p.161.1.17. Jeleottiy; p. I,i I.r.2x : I. 1 1. dele the Semicolon : 1. 17. r. place : p. 167.1. 4o,r.iz;p. I7».1.i8. r. <i»d /or fie .* p. ipi.l.lT.i.and an artific. p- and frtmthe :
p. tn.l. 4. t.whence the under: p.z34.1.i i.i.tohope-. p.238,I,4t.r.iXK0f left t f.i4oA,i9,t.Moon.
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