Transcriber's notes.
The Errata of the printed book have all been corrected. They were as follows:
Pag. 142. l. 20. These words, And to manifest, with the rest of what is by a mistake further printed in this fourth Experiment, belongeth, and is to be referred to the end of the second Eperiment, p.137. pag. 145. l. 1. leg. matter. 146. l. 4. leg. Bolts-head. pag 161. in the marginal note l. 2. dele de ib. l. 3. lege lib 1. p 163. l. ult. insert where between the words places and the. p. 164 l. 1. dele that. ibid, l. 8. leg Epidermis. ibid. l. 19 leg. 300. for 200. p. 169. l. 22. leg. into it. p. 170. l. 23. & 24. leg. Some Solutions hereafter to be mentioned, for the Solutions of Potashes, and other Lixiviate Salts. p. 171. l. 6. insert part of between the words most and dissolved p. 176. l. ult. insert the participle it between the words Judged and not p. 234. l. 4. leg. Woud-wax or Wood-wax. p. 320 l. 29. leg. urine for urne.
In addition I have corrected the following original typos:
The preface: I devis'd tbem -> I devis'd them
The preface: make
Expements -> make Experiments
The Publisher to the reader: made of
Eperiments -> made of Experiments
I. Ch. III.6 divers Expements ->
divers Experiments
I. Ch. III.13 epecially with some sorts ->
especially with some sorts
II. Ch. II.8 Slightet Texture -> Slightest
Texture
II. Exp. I two Colonrs -> two Colours
II. Exp. XIII were
the change of Colour ... is attempted -> where the change (etc.)
III.
Exp. XII avoiding of Ambignity -> avoiding of Ambiguity
III. Exp.
XXIX Juice of this Sipce -> Juice of this Spice
III. Exp. XL forty
second Expement -> forty second Experiment
III. Exp. XLIV keep them
swimning -> keep them swimming
III. Exp. XLVI it seem'd propable to
me -> it seem'd probable to me
III. Exp. XLVII where not comprehended
-> were not comprehended
III. Exp. XLVIII frequent Igintion ->
frequent Ignition
III. Exp. L I could tell yon -> I could tell you
A Copy of the Letter: nemo unqnam vere asserere -> nemo nunquam vere
asserere
(ib.): what is reladed -> what is related
Observations:
carefulsy drawn -> carefully drawn
- and emended
Phœnomenon/a to Phænomenon/a 10 times and
Cœruleous
etc. -> Cæruleous 20 times
EXPERIMENTS
AND
CONSIDERATIONS
Touching
COLOURS.
Firſt occaſionally Written, among ſome other
Eſſays,
to a Friend; and now ſuffer'd to
come abroad as
THE
BEGINNING
Of An
Experimental
Hiſtory
OF
COLOURS.
By the Honourable ROBERT BOYLE,
Fellow of the ROYAL SOCIETY.
Non fingendum, aut excogitandum, ſed inveniendum,
quid Natura
faciat, aut ferat. Bacon.
LONDON.
Printed for Henry Herringman at the
Anchor on the Lower
walk of the New
Exchange. MDCLXIV.
THE
PREFACE.
Aving in convenient places of the following Treatiſe, mention'd the Motives, that induc'd me to write it, and the Scope I propos'd to my ſelf in it; I think it ſuperfluous to entertain the Reader now, with what he will meet with hereafter. And I ſhould judge it needleſs, to trouble others, or my ſelf, with any thing of Preface: were it not that I can ſcarce doubt, but this Book will fall into the hands of ſome Readers, who being unacquainted with the difficulty of attempts of this nature, will think itn ſtrange that I ſhould publiſh any thing about Colours, without a particular Theory of them. But I dare expect that Intelligent and Equitable Readers will conſider on my behalf: That the profeſſed Deſign of this Treatiſe is to deliver things rather Hiſtorical than Dogmatical, and conſequently if I have added divers new ſpeculative Conſiderations and hints, which perhaps may afford no deſpicable Aſſiſtance, towards the framing of a ſolid and comprehenſive Hypotheſis, I have done at least as much as I promis'd, or as the nature of my undertaking exacted. But another thing there is, which if it ſhould be objected, I fear I ſhould not be able ſo eaſily to anſwer it, and that is; That in the following treatiſe (eſpecially in the Third part of it) the Experiments might have been better Marſhall'd, and ſome of them deliver'd in fewer words. For I muſt confeſs that this Eſſay was written to a private Friend, and that too, by ſnatches, at ſeveral times, and places, and (after my manner) in looſe ſheets, of which I oftentimes had not all by me that I had already written, when I was writing more, ſo that it needs be no wonder if all the Experiments be not rang'd to the beſt Advantage, and if ſome connections and conſecutions of them might eaſily have been mended. Eſpecially ſince having careleſſly laid by the looſe Papers, for ſeveral years after they were written, when I came to put them together to diſpatch them to the Preſs, I found ſome of thoſe I reckon'd upon, to be very unſeaſonably wanting. And to make any great change in the order of the reſt, was more than the Printers importunity, and that, of my own avocations (and perhaps alſo conſiderabler ſolicitations) would permit. But though ſome few preambles of the particular Experiments might have (perchance) been ſpar'd, or ſhorten'd, if I had had all my Papers under my View at once; Yet in the moſt of thoſe Introductory paſſages, the Reader will (I hope) find hints, or Advertiſements, as well as Tranſitions. If I ſometimes ſeem to inſiſt long upon the circumſtances of a Tryall, I hope I ſhall be eaſily excuſed by thoſe that both know, how nice divers experiments of Colours are, and conſider that I was not barely to relate them, but ſo as to teach a young Gentleman to make them. And if I was not ſollicitous, to make a nicer diviſion of the whole Treatiſe, than into three parts, whereof the One contains ſome Conſiderations about Colours in general. The Other exhibits a ſpecimen of an Account of particular Colours, Exemplifi'd in Whiteneſs and Blackneſs. And the Third promiſcuous Experiments about the remaining Colours (eſpecially Red) in order to a Theory of them. If, I ſay, I contented my ſelf with this eaſie Diviſion of my Diſcourſe, it was perhaps becauſe I did not think it ſo neceſſary to be Curious about the Method or Contrivance of a Treatiſe, wherein I do not pretend to preſent my Reader with a compleat Fabrick, or ſo much as Modell; but only to bring in Materials proper for the Building; And if I did not well know how Ingenious the Curioſity and Civility of Friends makes them, to perſwade Men by ſpecious allegations, to gratifie their deſires; I ſhould have been made to believe by perſons very well qualify'd to judge of matters of this nature, that the following Experiments will not need the addition of accurate Method and ſpeculative Notions to procure Acceptance for the Treatiſe that contains them: For it hath been repreſented, That in moſt of them, as the Novelty will make them ſurprizing, and the Quickneſs of performance, keep them from being tedious; ſo the ſenſible changes, that are effected by them, are ſo manifest, ſo great, and ſo ſudden, that ſcarce any will be diſpleaſed to ſee them, and thoſe that are any thing Curious will ſcarce be able to ſee them, without finding themſelves excited, to make Reflexions upon Them. But though with me, who love to meaſure Phyſical things by their uſe, not their ſtrangeneſs, or prettineſs, the partiality of others prevails not to make me over value theſe, or look upon them in themſelves as other than Trifles: Yet I confeſs, that ever ſince I did divers years ago ſhew ſome of them to a Learned Company of Virtuoſi: ſo many perſons of differing Conditions, and ev'n Sexes, have been Curious to ſee them, and pleas'd not to Diſlike them, that I cannot Deſpair, but that by complying with thoſe that urge the Publication of them, I may both gratifie and excite the Curious, and lay perhaps a Foundation whereon either others or my ſelf may in time ſuperſtruct a ſubſtantial theory of Colours. And if Ariſtotle, after his Maſter Plato, have rightly obſerv'd Admiration to be the Parent of Philoſophy, the wonder, ſome of theſe Trifles have been wont to produce in all ſorts of Beholders, and the acceſs they have ſometimes gain'd ev'n to the Cloſets of Ladies, ſeem to promiſe, that ſince the ſubject is ſo pleaſing, that the Speculation appears as Delightful! as Difficult, ſuch eaſie and recreative Experiments, which require but little time, or charge, or trouble in the making, and when made are ſenſible and ſurprizing enough, may contribute more than others, (far more important but as much more difficult) to recommend thoſe parts of Learning (Chymistry and Corpuſcular Philoſophy) by which they have been produc'd, and to which they give Teſtimony ev'n to ſuch kind of perſons, as value a pretty Trick more than a true Notion, and would ſcarce admit Philoſophy, if it approach'd them in another Dreſs: without the ſtrangeneſs or endearments of pleaſantneſs to recommend it. I know that I do but ill conſult my own Advantage in the conſenting to the Publication of the following Treatiſe: For thoſe things, which, whilſt men knew not how they were perform'd, appear'd ſo ſtrange, will, when the way of making them, and the Grounds on which I devis'd them, ſhall be Publick, quickly loſe all that their being Rarityes, and their being thought Myſteries, contributed to recommend them. But 'tis fitter for Mountebancks than Naturalis to deſire to have their diſcoverys rather admir'd than underſtood, and for my part I had much rather deſerve the thanks of the Ingenious, than enjoy the Applauſe of the Ignorant. And if I can ſo farr contribute to the diſcovery of the nature of Colours, as to help the Curious to it, I ſhall have reach'd my End, and ſav'd my ſelf ſome Labour which elſe I may chance be tempted to undergo in proſecuting that ſubect, and Adding to this Treatiſe, which I therefore call a History, becauſe it chiefly contains matters of fact, and which Hiſtory the Title declares me to look upon but as Begun: Becauſe though that above a hundred, not to ſay a hundred and fifty Experiments, (ſome looſe, and others interwoven amongſt the diſcourſes themſelves) may ſuffice to give a Beginning to a Hiſtory not hitherto, that I know, begun, by any; yet the ſubject is ſo fruitfull, and ſo worthy, that thoſe that are Curious of theſe Matters will be farr more wanting to themſelves than I can ſuſpect, if what I now publiſh prove any more than a Beginning. For, as I hope my Endeavours may afford them ſome aſſistance towards this work, ſo thoſe Endeavours are much too Vnfiniſh'd to give them any diſcouragement, as if there were little left for others to do towards the Hiſtory of Colours.
For (firſt) I have been willing to leave unmention'd the moſt part of thoſe Phænomena of Colours, that Nature preſents us of her own accord, (that is, without being guided or over-ruld by man) ſuch as the different Colours that ſeveral ſorts of Fruites paſs through before they are perfectly ripe, and thoſe that appear upon the fading of flowers and leaves, and the putrifaction (and its ſeveral degrees) of fruits, &c. together with a thouſand other obvious Instances of the changes of colours. Nor have I much medled with thoſe familiar Phænomena wherein man is not an Idle ſpectator; ſuch as the Greenneſs produc'd by ſalt in Beef much powder'd, and the Redneſs produc'd in the ſhells of Lobſters upon the boyling of thoſe fiſhes; For I was willing to leave the gathering of Obſervations to thoſe that have not the Opportunity to make Experiments. And for the ſame Reaſons, among others, I did purpoſly omit the Lucriferous practiſe of Trades-men about colours; as the ways of making Pigments, of Bleanching wax, of dying Scarlet, &c. though to divers of them I be not a stranger, and of ſome I have myſelf made Tryall.
Next; I did purpoſely paſs by divers Experiments of other Writers that I had made Tryall of (and that not without regiſtring ſome of their Events) unleſs I could ſome way or other improve them, becauſe I wanted leaſure to inſert them, and had thoughts of proſecuting the work once begun of laying together thoſe I had examin'd by themſelves in caſe of my not being prevented by others diligence. So that there remains not a little, among the things that are already publiſhed, to imploy thoſe that have a mind to exerciſe themſelves in repeating and examining them. And I will not undertake, that none of the things deliver'd, ev'n in this Treatiſe, though never ſo faithfully ſet down, may not prove to be thus farr of this Sort, as to afford the Curious ſomewhat to add about them. For I remember that I have ſomewhere in the Book it ſelf acknowledged, that having written it by ſnatches, partly in the Counntrey, and partly at unſeaſonable times of the year, when the want of fit Inſtruments, and of a competent variety of flowers, ſalts, Pigments, and other materials made me leave ſome of the following Experiments, (eſpecialy thoſe about Emphatical Colours) far more unfiniſh'd than they ſhould have been, if it had been as eaſie for me to ſupply what was wanting to compleat them, as to diſcern. Thirdly to avoyd diſcouraging the young Gentleman I call Pyrophilus, whom the leſs Familiar, and more Laborious operations of Chymistry would probably have frighted, I purpoſely declin'd in what I writ to him, the ſetting down any Number of ſuch Chymicall Experiments, as, by being very elaborate or tedious, would either require much skill, or exerciſe his patience. And yet that this ſort of Experiments is exceedingly Numerous, and might more than a little inrich the Hiſtory of Colours, thoſe that are vers'd in Chymical proceſſes, will, I preſume, eaſily allow me.
And (Laſtly) for as much as I have occaſion more than once in my ſeveral Writings to treat either porpoſely or incidentally of matters relating to Colours; I did not, perhaps, conceive my ſelf oblig'd, to deliver in one Treatiſe all that I would ſay concerning that ſubject.
But to conclude, by ſumming up what I would ſay concerning what I have and what I have not done, in the following Papers; I ſhall not (on the one ſide) deny, that conſidering that I pretended not to write an accurate Treatiſe of Colours, but an Occaſional Eſſay to acquaint a private friend with what then occurrd to me of the things I had thought or try'd concerning them; I might preſume I did enough for once, if I did clearly and faithfully ſet down, though not all the Experiments I could, yet at leaſt ſuch a variety of them, that an attentive Reader that ſhall conſider the Grounds on which they have been made, and the hints that are purpoſely (though diſperſedly) couched in them, may eaſily compound them, and otherwiſe vary them, ſo as very much to increaſe their Number. And yet (on the other ſide) I am ſo ſenſible both of how much I have, either out of neceſſity or choice, left undone, and of the fruitfullneſs of the ſubject I have begun to handle; that though I had performed far more then 'tis like many Readers will judge I have, I ſhould yet be very free to let them apply to my Attempts that of Seneca, where having ſpoken of the Study of Natures Myſteries, and Particularly of the Cauſe of Earth-Quakes, he ſubjoins.1 Nulla res conſummata eſt dum incipit. Nec in hac tantum re omnium maxima ac involutiſſimá, in quâ etiam cum multum actum erit, omnis ætas, quod agat inveniet; ſed in omni alio Negotio, longè ſemper à perfecto fuere Principia.
The Publiſher to the
READER.
Friendly Reader,
Ere is preſented to thy view one of the Abſtruſeſt as well as the Gentileſt Subjects of Natural Philoſophy, the Experimentall Hiſtory of Colours; which though the Noble Author be pleaſed to think but Begun, yet I muſt take leave to ſay, that I think it ſo well begun, that the work is more than half diſpatcht. Concerning which I cannot but give this advertiſement to the Reader, that I have heard the Author expreſs himſelf, that it would not ſurpriſe him, if it ſhould happen to be objected, that ſome of theſe Experiments have been already publiſhed, partly by Chymiſts, and partly by two or three very freſh Writers upon other Subjects. And though the number of theſe Experiments be but very ſmall, and though they be none of the conſiderableſt, yet it may on this occaſion be further repreſented, that it is eaſie for our Author to name ſeveral men, (of whoſe number I can truly name my ſelf) who remember either their having ſeen him make, or their having read, his Accounts of the Experiments delivered in the following Tract ſeveral years ſince, and long before the publication of the Books, wherein they are mentioned. Nay in divers paſſages (where he could do it without any great inconvenience) he hath ſtruck out Experiments, which he had tryed many years ago, becauſe he ſince found them divulged by perſons from whom he had not the leaſt hint of them; which yet is not touched, with deſign to reflect upon any Ingenious Man, as if he were a Plagiary: For, though our Generous Author were not reſerved enough in ſhowing his Experiments to thoſe that expreſſed a Curioſity to ſee them (amongſt whom a very Learned Man hath been pleaſed publickly to acknowledge it ſeveral years ago2; yet the ſame thing may be well enough lighted on by perſons that know nothing of one another. And eſpecially Chymical Laboratories may many times afford the ſame Phænomenon about Colours to ſeveral perſons at the ſame or differing times. And as for the few Phænomena mentioned in the ſame Chymical writers, as well as in the following Treatiſe, our Author hath given an account, why he did not decline rejecting them, in the Anotations upon the 47th Experiment of the third part. Not here to mention, what he elſewhere ſaith, to ſhew what uſe may be Juſtifiably made of Experiments not of his own deviſing by a writer of Natural Hiſtory, if, what he employes of others mens, be well examined or verified by himſelf.
In the mean time, this Treatiſe is ſuch, that there needs no other invitation to peruſe it, but that tis compoſed by one of the Deepeſt & Moſt indefatigable ſearchers of Nature, which, I think the World, as far as I know it, affords. For mine own part, I feel a Secret Joy within me, to ſee ſuch beginings upon ſuch Themes, it being demonſtratively true, Mota facilius moveri, which cauſeth me to entertain ſtrong hopes, that this Illuſtrious Virtuoſo and Reſtleſs Inquirer into Nature's Secrets will not ſtop here, but go on and proſper in the Diſquiſition or the other principal Colours, Green, Red, and Yellow. The Reaſoning faculty ſet once afloat, will be carried on, and that with eaſe, eſpecially, when the productions thereof meet, as they do here, with ſo greedy an Entertainment at home and abroad. I am confident, that the ROYAL SOCIETY, lately conſtituted by his MOST EXCELLENT MAJESTY for improving Natural knowledge, will Judge it their intereſt to exhort our Author to the proſecution of this Argument, conſidering, how much it is their deſign and buſineſs to accumulate a good ſtock of ſuch accurate Obſervations and Experiments, as may afford them and their Offpring genuine Matter to raiſe a Maſculine Philoſophy upon, whereby the Mind of Man may be enobled with the Knowledge of ſolid Truths, and the Life of Man benefited with ampler accommodations, than it hath been hitherto.
Our Great Author, one of the Pillars of that Illuſtrious Corporation, is conſtantly furniſhing large Symbola's to this work, and is now falln, as you ſee, upon ſo comprehenſive and important a theme, as will, if inſiſted on and compleated, prove one of the conſiderableſt peeces of that ſtructure. To which, if he ſhall pleaſe to add his Treatiſe of Heat and Flame, as he is ready to publiſh his Experimental Accounts of Cold, I eſteem, the World will be obliged to Him for having ſhewed them both the Right and Left Hand of Nature, and the Operations thereof.
The conſidering Reader will by this very Treatiſe ſee abundant cauſe to ſollicit the Author for more; ſure I am, that of whatever of the Productions of his Ingeny comes into Forein parts (where I am happy in the acquaintance of many intelligent friends) is highly valued; And to my knowledge, there are thoſe among the French, that have lately begun to learn Engliſh, on purpoſe to enable themſelves to read his Books, being impatient of their Traduction into Latin. If I durſt ſay all, I know of the Elogies received by me from abroad concerning Him, I ſhould perhaps make this Preamble too prolix, and certainly offend the modeſty of our Author.
Wherefore I ſhall leave this, and conclude with deſiring the Reader, that if he meet with other faults beſides thoſe, that the Errata take notice of (as I believe he may) he will pleaſe to conſider both the weakneſs of the Authors eyes, for not reviewing, and the manifold Avocations of the Publiſher for not doing his part; who taketh his leave with inviting thoſe, that have alſo conſidered this Nice ſubject experimentally, to follow the Example of our Noble Author, and impart ſuch and the like performances to the now very inquiſitive world. Farewell.
THE
CONTENTS.
CHAP. I.
The Author ſhews the Reaſon, first of his Writing on this Subject (1.) Next of his preſent manner of Handling it, and why he partly declines a Methodical way (2.) and why he has partly made uſe of it in the Hiſtory of Whiteneſs and Blackneſs. (3.)
Chap. 2. Some general Conſiderations are premis'd, firſt of the Inſignificancy of the Obſervaſion of Colours in many Bodies (4, 5.) and the Importance of it in others (5.) as particularly in the Tempering of Steel (6, 7, 8.) The reaſon why other particular Inſtances are in that place omitted (9) A neceſſary diſtinction about Colour premis'd (10, 11.) That Colour is not Inherent in the Object (11.) prov'd firſt by the Phantaſms of Colours to Dreaming men, and Lunaticks; Secondly by the ſenſation or apparition of Light upon a Blow given the Eye or the Diſtemper of the Brain from internal Vapours (12.) The Author recites a particular Instance in himſelf; another that hapn'd to an Excellent Perſon related to him (13.) and a third told him by an Ingenious Phyſician (14, 15.) Thirdly, from the change of Colours made by the Senſory Diſaffected (15, 16.) Some Inſtances of this are related by the Author, obſerv'd in himſelf (16, 17.) others told him by a Lady of known Veracity (18.) And others told him by a very Eminent Man (19.) But the ſtrange Inſtances afforded by ſuch as are Bit by the Tarantula are omitted, as more properly deliver'd in another place. (20.)
Chap. 3. That the Colour of Bodies depends chiefly on the diſpoſition of the Superficial parts, and partly upon the Variety of the Texture of the Object (21.) The former of theſe are confirm'd by ſeveral Perſons (22.) and two Inſtances, the firſt of the Steel mention'd before, the ſecond of melted Lead (23, 24.) of which laſt ſeveral Obſervables are noted (25.) A third Inſtance is added of the Porouſneſs of the appearing ſmooth Surface of Cork (26, 27.) And that the ſame kind of Porouſneſs may be alſo in the other Colour'd Bodies; And of what kind of Figures, the Superficial reflecting Particles of them may be (28.) and of what Bulks, and cloſeneſs of Poſition (29.) How much theſe may conduce to the Generation of Colour inſtanc'd in the Whiteneſs of Froth, and in the mixtures of Dry colour'd Powders (30.) A further explication of the Variety that may be in the Superficial parts of Colour'd Bodies, that may cauſe that Effect, by an example drawn from the Surface of the Earth (31.) An Apology for that groſs Compariſon (32.) That the appearances of the Superficial aſperities may be Varied from the poſition of the Eye, and ſeveral Inſtances given of ſuch appearances (33, 34, 35.) That the appearance of the Superficial particles may be Varied alſo by their Motion, confirm'd by an Inſtance of the ſmoaking Liquor (35.) eſpecially if the Superficial parts be of ſuch a Nature as to appear divers in ſeveral Poſtures, explain'd by the variety of Colours exhibited by the ſhaken Leaves of ſome Plants (36.) and by changeable Taffities (37, 38, 39.) The Authors wiſh that the Variety of Colours in Mother of Pearl were examin'd with a Microſcope (40.) And his Conjectures, that poſſibly good Microſcopes might diſcover thoſe Superficial inequalities to be Real, which we now only imagine with his reaſons drawn partly from the Diſcoveries of the Teleſcope, and Microſcope (41.) And partly alſo from the Prodigiouſly ſtrange example of a Blind man that could feel Colours (42.) whoſe Hiſtory is Related (43, 44, 45.) The Authors conjecture and thoughts of it (46, 47, 48, 49.) and ſeveral Concluſions and Corollaries drawn from it about the Nature of Blackneſs and Black Bodies (50, 51, 52.) and about the Aſperities of ſeveral other Colour'd Bodies (53.) And from theſe, and ſome premis'd Conſiderations, are propos'd ſome Conjectures; That the reaſon of the ſeveral Phænomena of Colours, afterwards to be met with, depends upon the Diſpoſition of the Seen parts of the Object (54.) That Liquors may alter the Colours of each other, and of other Bodies, first by their Inſinuating themſelves into the Pores, and filling them, whence the Aſperity of the Surface of a Body becomes alter'd, explicated with ſome Inſtances (55, 56.) Next by removing thoſe Bodies, which before hindred the appearance of the Genuine Colour, confirm'd by ſeveral examples (57) Thirdly, by making a Fiſſure or Separation either in the Contiguous or Continued Particles of a Body (58.) Fourthly, by a Union or Conjunction of the formerly ſeparated Particles; Illuſtrated with divers Inſtances of precipitated Bodies (59.) Fifthly, by Diſlocating the parts, and putting them both into other Orders and Poſtures, which is Illuſtrated with Inſtances (60, 61.) Sixthly, by Motion, which is explain'd (62.) And laſtly, and chiefly, by the Union of the Saline Bodies, with the Superficial parts of another Body, whereby both their Bigneſs and Shape muſt neceſſarily be alter'd (63, 64.) Explain'd by Experiments (65, 66.) That the Colour of Bodies may be Chang'd by the concurrence of two or more of theſe ways (67.) And beſides all theſe, Eight Reflective cauſes of Colours, there may be in Tranſparent Bodies ſeveral Refractive (68, 69) Why the Author thinks the Nature of Colours deſerves yet a further Inquiry (69.) Firſt for that the little Motes of Dust exhibited very lovely Colours in a darkned Room, whilſt in a convenient poſture to the Eye, which in other Poſtures and Lights they did not (70.) And that though the ſmaller Parts of ſome Colour'd Bodies are Tranſparent, yet of others they are not, ſo that the firſt Doubt's, whether the Superficial parts create thoſe Colours, and the ſecond, whether there be any Refraction at all in the later (71, 72, 73.) A famous Controverſie among Philoſophers, about the Nature of Colour decided. (74. 75.)
Chap. 4. The controverſie ſtated about Real and Emphatical Colours (75, 76.) That the great Diſparity between them ſeems to be, partly their Duration in the ſame ſtate, and partly, that Genuine Colours are produc'd in Opacous Bodies by Reflection, and Emphatical in Tranſparent by Refraction (78.) but that this is not to be taken in too large a Senſe, the Cautionary inſtance of Froth is alleged and inſiſted on (78, 79.) That the Duration is not a ſufficient Characteristick, exemplify'd by the duration of Froth, and other Emphatical Colours, and the ſuddain fading of Flowers, and other Bodies of Real ones (80.) That the poſition of the Eye is not neceſſary to the diſcerning Emphatical Colours, ſhew'd by the ſeeing white Froth, or an Iris caſt on the Wall by a Priſm, in what place of the Room ſoever the Eye be (81.) which proceeds from the ſpecular Reflection of the Wall (82.) that Emphatical Colours may be Compounded, and that the preſent Diſcourſe is not much concern'd, whether there be, or be not made a diſtinction between Real and Emphatical Colours. (83.)
Chap. 5. Six Hypotheſes about Colour recited (84, 85) Why the Author cannot more fully Speak of any of theſe (86.) nor Acquieſce in them (87, 88.) What Pyrophilus is to expect in this Treatiſe (88, 89.) What Hypotheſis of Light and Colour the Author most inclines too (90.) Why he thinks neither that nor any other ſufficient; and what his Difficulties are, that make him decline all Hypotheſes, and to think it very difficult to ſtick to any. (91, 92.)
Part the Second.
Of the Nature of Whiteneſs and Blackneſs.
CHAP. I.
The reaſon why the Author choſe the Explication of Whiteneſs and Blackneſs (93.) Wherein Democritus thought amiſs of theſe (94.) Gaſſendus his Opinion about them (95.) What the Author approves, and a more full Explication of White, makinig it a Multiplicity of Light or Reflections (96, 97.) Confirm'd first by the Whiteneſs of the Meridian Sun, obſerv'd in Water (98.) and of a piece of Iron glowing Hot (99.) Secondly, by the Offenſiveneſs of Snow to the Travellers eyes, confirm'd by an example of a Perſon that has Travell'd much in Ruſſia (100.) and by an Obſervation out of Olaus Magnus (100.) and that the Snow does inlighten and clear the Air in the Night, confirm'd by the Moſco Phyſician, and Captain James (101.) But that Snow has no inherent Light, prov'd by Experience (102.) Thirdly, by the great ſtore of Reflections, from white Bodies obſerv'd in a darkned Room, and by their unaptneſs to be Kindled by a Burning-glaſs (103.) Fourthly, the Specularneſs of White Bodies is confirm'd by the Reflections in a dark Room from other Bodies (104.) and by the appearance of a River, which both to the Eye and in a darkned Room appear'd White (105, 106.) Fifthly, by the Whiteneſs of diſtill'd Mercury, and that of the Galaxie (107, 108.) and by the Whiteneſs of Froth, rais'd from whites of Eggs beaten; that this Whiteneſs comes not from the Air, ſhew'd by Experiments (109, 110.) where occaſionally the Whiteneſs of Diſtill'd Oyls, Hot water, &c. are ſhew'd (111.) That it ſeems not neceſſary the Reflecting Surfaces ſhould be Sphærical, confirm'd by Experiments (112, 113.) Sixthly, by the Whiteneſs of the Powders of tranſparent Bodies (114.) Seventhly, by the Experiment of Whitening and Burniſhing Silver. (115, 116.)
Chap. 2. A Recital of ſome Opinions about Blackneſs, and which the Author inclines to (117.) which he further inſists on and explicates (118, 119.) and ſhews for what reaſons he imbrac'd that Hypotheſis (120.) Firſt, from the contrary Nature of Whiteneſs and Blackneſs, White reflecting moſt Beams outwards, Black ſhould reflect moſt inward (120.) Next, from the Black appearance of all Bodies, when Shadow'd; And the manner how this paucity of Reflection outwards is caus'd, is further explicated, by ſhewing that the Superficial parts may be Conical and Pyramical (121.) This and other Conſiderations formerly deliver'd, Illuſtrated by Experiments with black and white Marble (122, 123.) Thirdly, from the Black appearance of Holes in white Linnen, and from the appearance of Velvet ſtroak'd ſeveral ways, and from an Obſervation of Carrots (124, 125.) Fourthly, from the ſmall Reflection from Black in a darkned Room (125, 126.) Fifthly, from the Experiment of a Checker'd Tile expos'd to the Sun-beams (127.) which is to be preferr'd before a Similar Experiment try'd in Italy, with black and white Marble (128.) Some other congruous Obſervations (129.) Sixthly, from the Roaſting black'd Eggs in the Sun (130.) Seventhly, by the Obſervation of the Blind man lately mention'd, and of another mention'd by Bartholine (130.) That notwithſtanding all theſe Reaſons, the Author is not abſolutely Poſitive, but remains yet a Seeker after the true Nature of Whiteneſs and Blackneſs. (131, 132.)
Experiments in Conſort, touching Whiteneſs and Blackneſs.
The firſt Experiment, with a Solution of Sublimate, made White with Spirit of Urine, &c. (133, 134.)
The ſecond Experiment, with an Infuſion of Galls, made Black with Vitriol, &c. (135, 136.) further Diſcours'd of (137.)
The third Experiment, of the Blacking of Hartſhorn, and Ivory, and Tartar, and by a further Calcination making them White (138, 139.)
The fourth Experiment, limiting the Chymiſt's principle, Aduſta nigra ſed peruſta alba, by ſeveral Inſtances of Calcin'd Alabaſter, Lead, Antimony, Vitriol, and by the Teſtimony of Bellonius, about the white Charcoles of Oxy-cædar, and by that of Camphire. (140, 141, 142.) That which follows about Inks was miſplac'd by an Errour of the Printer, for it belongs to what has been formerly ſaid of Galls (142, 143.)
The fifth Experiment, of the black Smoak of Camphire (144.)
The ſixth Experiment, of a black Caput Mortuum, of Oyl of Vitriol, with Oyl of Worm-word, and alſo with Oyl of Winter-Savory (145.)
The ſeventh Experiment, of whitening Wax (146.)
The eighth Experiment, with Tin-glaſs, and Sublimate (147, 148.)
The ninth Experiment, of a Black powder of Gold in the bottom of Aqua-fortis, and of the Blacking of Refin'd Gold and Silver (148, 149.)
The tenth Experiment, of the ſtaining Hair, Skin, Ivory, &c. Black, with Cryſtals of Silver (150, 151.)
The eleventh Experiment, about the Blackneſs of the Skin, and Hair of Negroes, and Inhabitants of Hot Climates. Several Objections are made, and the whole Matter more fully diſcours'd and ſtated from ſeveral notable Hiſtories and Obſervations (from the 151 to the 167.)
The twelfth Experiment, of the white Powders, afforded by Precipitating ſeveral Bodies, as Crabs Eyes, Minium, Coral, Silver, Lead, Tin, Quick-ſilver, Tin-glaſs, Antimony, Benzoin, and Reſinous Gumms out of Spirit of Wine, &c. but this is not Univerſal, ſince other Bodies, as Gold, Antimony, Quick-ſilver, &c. may be Precipitated of other Colours (168, 169, 170.)
The thirteenth Experiment, of Changing the Blackneſs of ſome Bodies into other Colours (171, 172.) and of Whitening what would be Minium, and Copper, with Tin, and of Copper with Arſnick, which with Coppilling again Vaniſhes; of covering the Colour of that of 1/3 of Gold with 2/3 of Silver melted in a Maſs together (173, 174)
The fourteenth Experiment, of turning the black Body of Horn into a White immediately with Scraping, without changing the Subſtantial form, or without the Intervention of Salt, Sulphur, or Mercury (176.)
The fifteenth Experiment, contains ſeveral Inſtances againſt the Opinion of the Chymiſts that Sulphur Aduſt is the cauſe of Blackneſs, and the whole Matter is fully diſcuſs'd and ſtated (from 176 to 184)
Part the Third.
Concerning Promiſcuous Experiments about Colours.
Experiment the Firſt.
IN confirmation of a former Conjecture about the Generation of Colours from diverſity of Reflections are ſet down ſeveral Obſervations made in a Darkned room (186, 187.)
Experiment the ſecond, That white Linnen ſeem'd Ting'd with the Red of Silk plac'd near it in a light Room (188,189.)
Experiment the third, Of the Trajection of Light through Colour'd Papers (189, 190.)
Experiment the fourth, Obſervations of a Priſm in a dark Room (191, 192.)
Experiment the fifth, Of the Refracting and Reflecting Priſmatical Colours in a light Room (193.)
Experiment the ſixth, On the Vaniſhing of the Iris of the Priſm, upon the acceſs of a greater adventitious Light (194.)
Experiment the ſeventh, Of the appearances of the ſame Colour'd Papers by Candle-light (195, 196).
Experiment the eighth, Of the Yellowneſs of the Flame of a Candle (197).
Experiment the ninth, Of the Greeniſh Blew tranſparency of Leaf Gold (198).
Experiment the tenth, Of the curious Tinctures afforded by Lignum Nephriticum (from 199 to 203). Several trials for the Inveſtigation of the Nature of it (from 204 to 206.) Kircher's relation of this Wood ſet down, and examin'd (from 206 to 212). A Corollary on this tenth Experiment, ſhewing how it may be applicable for the Diſcovering, whether any Salt be of an Acid, or a Sulphureous, and Alcalizate Nature (from 213 to 216).
The eleventh Experiment, Of certain pieces of Glaſs that afforded this Variety of Colours; And of the way of ſo Tinging any Plate of Glaſs with Silver (from 216 to 219).
The twelfth Experiment, Of the Mixing and Tempering of Painters Pigments (219, 220, 221).
The thirteenth Experiment, Of compounding ſeveral Colours by Trajecting the Sun-beams through Ting'd Glaſſes (from 221 to 224).
The fourteenth Experiment, Of the Compounding of Real and Phantaſtical Colours, and the Reſults (224, 225, 226.) as alſo the ſame of Phantaſtical Colours (226, 227.)
The fifteenth Experiment, Of Varying the Trajected Iris by a Colour'd Priſm (228, 229.)
The ſixteenth Experiment, Of the Red fumes of Spirit of Nitre, and, the reſembling Redneſs of the Horizontal Sun-beams (230, 231.)
The ſeventeenth Experiment, Of making a Green by nine Kinds of Compoſitions (from 231 to 236.) And ſome Deductions from them againſt the neceſſity of recurring to Subſtantial forms and Hypoſtatical principles for the production of Colours (from 237 to 240.)
The eighteenth Experiment, Of ſeveral Compoſitions of Blew and Yellow which produce not a Green, and of the production of a Green by other Colours (241, 242.)
The nineteenth Experiment, contains ſeveral inſtances of producing Colours, without the alteration of any Hypoſtatical principle, by the Priſm, Bubbles, and Feathers ( from 242 to 245.)
The twentieth Experiment Of turning the Blew of Violets into a Red by Acid Salts, and to a Green by Alcalizate (245, 246.) and the uſe of it for Inveſtigating the Nature of Salts (247, 248.)
The one and twentieth Experiment, of the ſame Changes effected by the ſame means on the Blew Tinctures of Corn-flowers (249, 250.) And ſome Reſtrictions to ſhew it not to be ſo general a propriety as one might imagine (251.)
The twenty ſecond Experiment, of turning a Solution of Verdigreaſe into a Blew, with Alcalizate and Urinous Salts (252, 253, 254.)
The twenty third Experiment, of taking away the Colour of Roſes with the Steams of Sulphur, and heightning them with the Steams Condens'd into Oyl of Sulphur per Campanam (254, 255.)
The twenty fourth Experiment, of Tinging a great quantity of Liquor with a very little Ting'd Subſtance, Inſtanced in Cochineel (from 255 to 257.)
The twenty fifth Experiment, of the more general uſe of Alcalizate and Sulphureous Salts in the Tinctures of Vegetables, further Inſtanced in the Tincture of Privet Berries, and of the Flowers of Meſereon and Peaſe (from 257 to 259.) An Annotation, ſhewing that of the three Hypoſtatical principles, Salt according to Paracelſus is the moſt active about Colours (from 259 to 261.) Some things Precurſory premis'd to three ſeveral Inſtances next following, againſt the fore-mention'd Operations of Salts (261, 262.)
The twenty ſixth Experiment, containing Trials with Acid and Sulphureous Salts on the Red Tinctures of Clove-july-flowers, Buckthorn Berries, Red-Roſes, Braſil, &c. (262, 263.)
The twenty ſeventh Experiment, of the changes of the Colour of Jaſmin flowers, and Snow drops, by Alcalizate and Sulphureous Salts (263, 264.)
The twenty eighth Experiment, of other differing Effects on Mary-golds, Prim-roſes, and freſh Madder (265.) with an Admonition, that theſe Salts may have differing Effects in the changing of the tinctures of divers other Vegetables (266, 267.)