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Robert Boyle's Account of a Degredation of Gold

This is an interesting piece by Robert Boyle in the form of allegorical discourse about the possibility of alchemical transmutation. It was first published under the title Of a Degradation of Gold made by an anti-elixir: a strange chymical narrative. London, 1678. This book is now extremely rare. The text below was transcribed for me by Justin von Bujdoss from the second edition, issued in London in 1739.
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After the whole Company had, as it were by Common Consent, continued silent for some time, which others spent in Reflections upon the Preceeding Conference, and Pyrophylus, in the Consideration of what he was about to Deliver; this Virtuoso at length stood up, an Addressing himself to the rest: "I hope, Gentlemen, sayes he, that what has been already Discoursed, has Inclined, if not Perswaded you to Think, That the Exaltation, or Change of other Metals into Gold, is not a Thing absolutely impossible; and, though I confess, I cannot remove all your Doubts and Objections, or my own, by being able to affirm to you, That I have with my own Hands made a Projection, (as Chymists are wont to call the sudden Transmutation made by a small Quantity of their admirable Elixir) yet I can confirm much of what hath been argued for the Possibility of such a sudden Change of a Metalline Body, by a Way, which, I presume, will suprise you: For, to make it more credible, that other Metals are capable of being graduated, or exalted into Gold by way of Projection, I will relate to you, that by the like way, Gold has been degraded, or imbased."

The Novelty of this Preamble having much suprised the Auditory, at length, Simplicius, with a disdainful Smile, told Pyrophilus: "That the Company would have much thanked him if he could have assured them, That he had seen another Metal exalted into Gold; but, that to find a Way of spoiling Gold, was not only a useless Discovery, but a prejudicial Practice."

Pyrophilus was going to make some Return to this Animadversion, when he was prevented by Artstander; who turning himself to Simpilcius, told him, with a Countenance and Tone that argued some Displeasure: "If Pyrophilus had been discoursing to a Company of Goldsmiths, or Merchants, your severe Reflection, upon what he said, would have been proper: But you might well have forborn it, if you had considered, as I suppose he did, that he was speaking to an Assembly of Philosophers and Virtuosi, who are wont to estimate Experiments, not as they inrich Mens Purses, but their Brains; and think Knowledge especially of uncommon Things very desirable, even when it is not accompanyed with any other Thing than the Light that still attends it, and idears it. It hath been thought an useful Secret, by a kind of Retrogradeation to turn Tin and Lead into brittle Bodies, like the Ores of those Metals. And if I thought it proper, I could shew, that such a change might be of use in the Investigation of the Nature of those Metals, besides the practical use that I know may be made of it. To find the Nature of Wine, we are assisted, not only by the methods of obtaining from it a Spirit; but by the ways of readily turning it into Vinegar: the knowledge of which ways hath not been despised by Chymists or Physitians, and hath at Paris, and divers other places, set up a profitable Trade. 'Tis well known that divers eminent Spagyrists have reckoned amongst their highest Arcana the ways by which they pretended, (and I fear did but pretend) to Extract the Mercury of Gold, and confrequently destroy that Metal; and 'twere not hard to shew by particular instances, that all the Experiments wherein Bodies are in some respects deteriorated, are not without distinction to be rejected or despised; since in some of them, the Light they may afford may more than countervail the Degredation of a small quantity of matter, though it be Gold itself. And indeed, (continues he) if we will consider things as Philosophers, and look upon them as Nature hath made them, not as Opinion hath disguised them; the Perogatives and usefulness of Gold in comparison of other Metals, is nothing near so great as Alchymists and Usures imagine. For, as it is true, that Gold is more ponderous, and more fixed, and perhaps more difficult to be spoiled, than Iron; yet the qualities (whereof the first makes it burthenson, and the two others serve chiefly but to distinguish the true from counterfeit) are so balanced by the hardness, stiffness, springless, and other useful qualities of Iron; that if those two Metals speak of (Gold and Iron) were equally plentiful in the World, it is scarce to be doubted, that Men would prefer the more useful before the more splendid, considering how much worse it were for Mankind to want Hatchets, and Knives and Swords, than Coin and Plate? Wherefore, (concludes he) I think Pyrophilus ought to be both desired and encouraged to go on with his intended Discourse, since whether Gold be or not be the Best of Metals; an afflurance that it may be degraded, may prove a Novelty very Instructive, and perhaps more so than the Transmutation of baser metals into a Nobler. For I remember it hath long passed for a Maxim among Chymical Philosophers, That Facilius est aurum construere quam destruere: And whatever becomes of that, 'tis certain that Gold being the closest, the constantest, and the least destructible of Metals, to be able to work a notable and almost Essential change in such a Body, (though, by deteriorating it) is more than to work a like change, (though in popular estimation for the better) in any Metal less indisposed to admit alterations, especially in such an one as Pyrophilus intimates, by telling us, that 'twas made by Way of Perfection, and consequently by a very small Proportion of active matter; whereas the destructions that Vulgar Chymists pretend to make of Gold, and wont to be attempted to be made by considerable proportions of Corrosive Menstruums, or other fretting Bodies; and even these, Experience shews to be usually too weak to ruine, though sometime they may much disguise the most Stable Texture of Gold. Cuncta adeo miris illic complexibus haerent."

Pyrophilus perceiving by several signs that he needed not add any thing of Apologetical to what Arristander had already said for him, resumed his Discourse, by saying, "I was going, Gentlemen, when Simplicius diverted me, to tell you, That looking upon the Vulgar Objections that have been wont to be framed against the possibility of Metalline Transmutions, from the Authority and Prejudices of Aristotle, and the School-Philosophers, as Arguments that in such an Assembly as this need not now be solemnly discussed; I consider that the difficulties that really deserve to be called so, and are of weight even with Mechanical Philosophers, and Judicious Naturalists, are principally these. First, That the great change that must be wrought by the Elixir, (if there be such an Agent) is effected upon Bodies of so stable and almost immutable a Nature as Metals. Next, That this great change is said to be brought to pass in a very short time. And thirdly, (which is yet more strange) That this great and suddain alteration is said to be effected by a very small, and perhaps inconsiderable, proportion of the transmuting Powder. To which three grand difficulties, I shall add another that to me appears, and perhaps will seem to divers of the new Philosophers, worthy to be lookt upon as a fourth, namely, The notable change that must by a real transmutation be made in the Specifick Gravity of the matter wrought upon: which difficulty I therefore think not unworthy to be added to the rest, because upon several tryals of my own and other men, I have found no known quality of Gold, (as its colour, malleableness, fixity, or the like) so difficult, if not so impossible, to be introduced into any other Metalline Matter, as the great Specifick Gravity that is peculiar to Gold. So that, Gentlemen, (concluded Pyrophilus) it can be made appear that Art has produced an Anti-Elixir, (if I may so call it) or Agent that is able in a very short time, to work a very notable, though deteriorating, change upon a Metal; in proportion to which, its quantity is very inconsiderable; I see not why it should be thought impossible that Art may also make a true Elixir, or a Powder capable of speedily Transmuting a great proportion of a baser Metal into Silver or Gold: especially if it be considered, that those that treate of these Arcana, confess that 'tis not every matter which may be justly called the Philosophers Stone, that is able to transmute other Metals in vast quantities; since several of these Writers, (an even Lully himself) make differing orders or degrees of the Elixir, and acknowledge, that a Medicine or Tincture of the first or lowest order will not transmute above ten times its weight of an inferior Metal."

Pyrophilus having at this part of his Discourse made a short pawse to take a breath, Crattippus took occasion from his silence to say to him, " I presume, Pyrophilus, I shall be disavowed by very few of these Gentlemen, if I tell you that the company is impatient to hear the Narrative of your Experiment, and that if it do so much as probably make out the particulars you have been mentioning, you will in likelyhood perswade most of them, and will certainly oblige them all. I shall therefore on their behalf as well as my own, sollicite you to hasten to the Historical part of a Discourse that is so like to gratifie our Curiosity."

The Company having by their unanimous silence, testified their approbation of what Crattippus had said; and appearing more than ordinarily attentive,

"As I was one day abroad," saith Pyrophilus, "to return visits to my Friends, I was by a happy Providence (for it was beside my first Intention) directed to make one to an ingenious Foreigner, with whom a few that I had recieved from him, had given me some little acguaintance.

Whilst this Gentleman and I were discoursing together of several matters, there came in to visit him a stranger, whom I had but once seen before; and though that were in a promiscuous company, yet he addressed himself to me in a way that quickly satisfied me of the greatness of his Civility; which he soon after also did of that of his Curiousity. For the Virtuoso, in whose Lodgings we met, having (to gratifie me) put him upon the discourse of his voyages; the curious stranger entertained us an hour or two with perteinent and judicious Answers to the Questions I askt him about places so remote, or so much within Land, that I had not met with any of our English Navigators or Travellers that had penetrated so far as to visit them. And because I found by his discourse that I was like to enjoy such good company but a very little while, (since he told me that he came the other day into England but to dispatch a business which he had already done as far as he could do it, after which he was with speed to return, as (to my trouble) he did to his Patron that sent him) I made the more haste to propose such Questions to him, as I most desired to be satisfied about; and among other things, enquiring whether in the Eastern parts he had traversed, he had met with any Chymists; he answered that he had; and that though they were fewer, and more reserved than ours, yet he did not find them all less skilful. And on this occasion, before he left the Town to go aboard the Ship he was to overtake; he in a very obliging way put into my hands at parting a little piece of Paper, folded up; which he said contained all that he had left of a rarity he had recieved from an Eastern Virtuoso, and which he intimated would give me occasion both to Remember him, and to exercise my thoughts in uncommon Speculations.

The great delight I took in conversing with a Person that had travelled so far, and could give me so good an account of what he had seen, made me so much resent the being so soon deprived of it, that though I judged such a Virtuoso would not, as a great token of his kindness, have presented me a trifle, yet the Present did but very imperfectly consoal me for the loss of so pleasing and instructive a Conversation.

Nevertheless, that I might comply with the curiosity he himself had excited in me, and know how much I was in his Debtor, I resolved to see what it was he had given me, and try whether I could make it do what I thought he Intimated, by the help of those few hints rather than directions how to use it, which the parting haste he was in (or perhaps some other reason best known to himself) confined him to give me. But in regard that I could not but think the Experiment would one way or another prove Extraordinary, I thought fit to take a Witness or two and an Assistant in the trying of it; and for that purpose made choice of an expernenced Doctor of Physick, very well versed in the separation and copelling of Metals."

"Though the Company (says Heliodorus) be so confident of your sincerity and wariness, that they would give credit even to unlikely Experiments, upon your single testimony; yet we cannot but approve your direction in taking an Assistant and a Witness, because in nice and uncommon Experiments we can scarce use too much circumspection, especially when we have not the means of reiterating the tryal: for in such new, as well as difficult cases, ‘tis easie even for a clear-sighted Experimenter to over-look some important circumstance, that a far less skilful by-stander may take notice of."

"As I have ever judged, (saith Pyrophilus) that cautiousness is a very requisite qualification for him that would satisfactorily make curious Experiments; so I thought fit to imploy a more than ordinary measure of it, in making a tryal, whose event I imagined might prove odd enough. And therefore having several time observed that some men are prepossessed, by having a particular Expectation raised in them, and are inclined to think that the do see that happen which they think they should see happen; I resolved to obviate this prejudication as much as innocently I could, and (without telling him anything but the truth, to which Philosophy as well as Religion obliges us to be strictly loyal) I told him but thus much of the truth, that I expected that a small proportion of a Powder presented me by a Foreign Virtuoso, would give a Brittleness to the most flexible and malleable of Metals, Gold it self. Which change I perceived he judged so considerable and unlikely to be affected, that he was greedy of seeing it severly tryed.

Having thus prepared him not to look for all that I my self expected, I caustiously opened the Paper I lately mentioned, but was both surprized and troubled, (as he also was) to find in it so very little Powder, that in stead of two differing tryals that I designed to make with it, there seemed very small hope that it would serve for one, (and that but an imperfect one neither.) For there was so very little Powder, that we could scarce see the colour of it, (save that as afar as I could judge it was of a darkish Red) and we thought it not only dangerous, but useless to attempt to weigh it, in regard we might easily lose it by putting it into, and out of the Balance; and the Weights we had were not small enough for so despicable a quantity of matter; which in words I estimated at an eighth part of a Grain; but my assistant, (whose conjecture I confess my thoughts inclined to prefer) would allow it to be at the most but a tenth of a Grain. Wherefore seeing the utmost we could reasonably hope to do with so very little Powder, was to make one tryal with it, we weighed out in differing Balances two Drams of Gold that had been formerly English Coyn, and that I caused by one that I usually imploy to be cupelled with a sufficient quantity of Lead, and quarted, as they speak, with refined Silver, and purged Aqua fortis, to be sure of the goodness of the Gold: these two Drams I put into a new Crucible, first carefully nealed, and having brought them to fusion by the meer action of the fire, without the help of Borax, or any other Additament, (which of course, though somewhat more laborious, than the most usual we took to obviate scruples) I put into the well melted Metal with my own hand the little parcel of Powder lately mentioned, and continuing the Vessel in the fire for about a quarter of an hour, that the Powder might have time to defuse it self everyway into the Metal, we poured out the well-melted Gold into another Crucible that I had brought with me, that had been gradually heated before to prevent cracking. But though from the first fusion of the Metal, to the pouring out, it had turned in the Crucible like ordinary Gold, save that once my Assistant told me he saw that for two or three moments it lookt almost like an Opale; yet I was somewhat suprized to find that when the matter was grown cold, that though it appeared upon the Balance that we had not lost anything of the weight we put in, yet instead of fine Gold, we had a lump of Metal of a dirty colour, and as it were overcast with a thin coat, almost like half vitrified Litharge; and somewhat to increase the wonder, we perceived that there stuck to one side of the Crucible a little Globule of Metal that lookt not at all yellowish, but like coarse Silver, and the bottom of the Crucible was overlaid with a vitrified substance, whereof one part was of a transparent yellow, and the other of a deep brown, inclining to red; and in this vitrified substance I could plainly perceive sticking at least five or six little Globules that lookt more like impure Silver than pure Gold. In short, this stuff lookt so little like refined, or so much as ordinary, Gold, that though my Friend did much more than I marvel at this change, yet I confes I was suprized at it myself. For though in some particulars it answered what I lookt for, yet in others, it was very differing from that which the Donor of the Powder had, as I though, given me ground to expect. Whether the cause of my disapointment were that (as I formerly intimated) this Virtuoso's haste or design made him leave me in the dark; or whether it were that finding myself in want of sufficient directions, I happily pitched upon such a proportion of Materials, and way of operating, as were proper to make a new Discovery, which the excellent Giver of the Powder had not Designed, or perhaps thought of."

"I shall not at all wonder," saith Cratippus, "either at your Friends amazement, or at your surprize, if your further tryals did in any measure confirm what the superficial change that appeared in your Metal could not but incline you to conjecture."

"You will best judge of that (replies Pyrophilus) by the account I was going to give you of what we did with our odd Metal. And First, having rubbed it upon a good Touchstone, whereon we had likewise rubbed a piece of Coined Gold, we manifestly found that the mark left upon the Stone by our Mass between the marks of the two other Metals, was notoriously more like the Touch of the Silver than that of the Gold. Next, having knockt our little lump with a Hammer, it was (according to my prediction) found brittle, and flew into several pieces. Thirdly, (which is more) even the insides of those peices lookt of a base dirty colour, like that of Brass or worse, for the fragments had a far greater resemblance to Bell-Metal, than either to Gold or Silver. To which we added this fourth, and more considerable, Examen; that having carefully weighed out one Dram of our stuff, (reserving the rest for tials to be suggested by second thoughts) and put it upon an excellent new and well nealed Coppel, with about half a dozen times its weight of Lead, we found, somewhat to our wonder, that though it turned very well like good Gold, yet it continued in the fire above an hour and a half, (which was twice as long as we expected) and yet almost to the very last the fumes copiously ascended, which sufficiently argued the operation to have been well carried on; and when at last it was quite ended, we found the Coppel very smooth and intire, but tinged with a fine purplish red, (which did somewhat surprize us, and besides, the refined Gold, there lay upon the cavity of the Coppel some dark coloured recements, which we concluded to have proceeded from the deteriorated Metal, not from the Lead. But when we came to put our Gold again into the Ballance we found it to weigh only about fifty three Grains, and consequently to have lost seven; which yet we found to be fully made up by that little quantity of recrements that I have lately mentioned, whose Weight and Fixity, compared with their unpromising Colour, did not puzzle us, especially because we had not enough of either of them, or of leisure, to examine their nature. To all which circumstances, I shall subjoin this, that to prevent any scruples that might arise touching the Gold we imployed, I caused a dram and a half that had been purposely reserved out of the same portion with that which had been debased; I caused this (I say) to be in my Assistants presence melted by it self, and found it (as I doubted not but I should do) fine and well-coloured Gold."

"I hope you will pardon my curiosity," saith Aristander, "to the gentleman that spoke last, if I ask why you take no notice of the effect of the Aqua fortis upon your imbased Metal?"

"Your Question," replies Pyrophilus, "I confess to be very reasonable, and I am somewhat troubled that I can't answer it but by telling you that we had not at hand any Aqua fortis, we durst relie on; which yet I was the less troubled at, because heretofore some tryals purposely made had informed me, that in some metalline Mixtures the Gold, if it were much predominant in quantity, may protect other Metal; (for instance Silver) from being dissolved by that Menstruum, though not from being at all invaded by it."

"There yet remained," saith Heliodorus, "one examen more of your odd Metal, which would have satisfied me, at least as much as any of the rest, of its having been notably imbased: for if it were altered in its Specifick Gravity, that quality I have always observed (as I lately perceived you also have done) to stick so close to Gold, that it could not by an additament so inconsiderable in point of bulk, be considerably altered without a notable and almost essential change in the texture of the Metal."

"To this pertinent discourse," Pyrophilus, with the respect due to a person that so worthily sustained the dignity he had of presiding in that choice company, made this return: "I owe you, Sir, my humble thanks for calling upon me to give you an account, I might have forgotten, and which is yet of so important a thing, that none of the other Phoenomina of our Experiment seemed to me to deserve so much notice. Wherefore I shall now inform you, that having my self of all the requisites to make Hydostatical Trials, (to which perhaps I am not altogether a stranger) I carefully weighed in water the ill-lookt Mass, (before it was divided for the coppelling of the above-mentioned dram) and found, to the great confirmation of my former wonder and conjectures, that instead of weighing about nineteen times as much as a bulk of water, equal to it, its proportion to that liquor was but that of fifteen, and about two thirds to one: so that its Specific Gravity was less by about 3-1/3 than it would if it had been pure Gold."

At the recital of this notable circumstance, superadded to the rest, the generality of the Company, and the President too, by looking and smiling upon one another, expressed themselves to be as well delighted as surprized; and after the murmuring occasioned by the various whispers that passed amongst them, was a little over, Heliodorus addressed himself to Pyrophilus, and told him, "I need not, and therefore shall not, stay for an express order from the Company to give you their hearty thanks: for as the obliging Stranger did very much gratifie you by the Present of his Wonderful Powder, so you have not a little gratified us by so candid and particular a Narritive of the effects of it; and I hope (continues he) that if you have not otherwise disposed of that part of that part of your deteriorated Gold that you did not coppel, you will sometime or another favour us with a sight of it."

"I join in this request," said Cratippus, as soon as he perceived the President had done speaking, and to facilitate the grant of it, "I shall not scruple to tell Pyrophilus he may be confident that the Degredation of his Gold will not depreciate it amongst Us: since if it to be allowable for Opinion to stamp such a value upon old coins and Medals, and in that Judgement of good antiquaries, a rusty piece of Brass or Copper, with a half defaced Image or Inscription on it, is to be highlier valued than as big a piece of well-stampt Gold; I see not why it should not be lawful for Philosophers to prize such a lump of depraved Gold as yours, before the finest Gold the Chymists and Mintmasters are wont to afford us. And though I freely grant that some old Copper Medals are of good use in History, to keep alive by their Inscriptions the memory of a taking of a Town, or the winning of a Battle; though these be but things that almost every day are some where or other done, yet I think Pyrophilus's imbased Metal is much to be preffered, as not only preserving the memory; but being an effect of such a Victory of Art over Nature, and the conquering of such generally believed insuperable difficulties, as no Story that I know of gives us an example of."

As soon as ever Cratippus had made a pause, Pyrophilus to prevent complimental discourse, did in a few words tell the President, That his part had been but that of a Relator of a matter of Fact, and that therefore he could deserve but little thanks and no praise at all; though a good measure of both of them were due to the obliging Virtuoso that had given him the Powder; and in that, the opportunity of complying with his duty, and his inclination, to serve that learned Company.

"Therefore Gentlemen (saith Aristander) are not persons among whom modesty is either restrained from expressing it self, or construed according to the Letter; and therefore whatever you have been pleased to say, the Company cannot but think itself much obliged to you; and I know the obligation would be much increased, if you would favour us with your reflections upon the extraordinary Experiment you have been pleased to relate to us."

"If," replies Pyrophilus, "I had had wherewithal to repeat the Experiment, and vary it according to the hints afforded me by the first trial, I should be less unfit to comply with Aristander's motion: but the Phoenomina are too new and too difficult for me to attempt to unriddle them by the help of so slender an information as a person so little sagatious as I could get by a single trial; and though I will not deny that I have had some raving thoughts about this puzzling subject, yet I hope I shall be easily pardoned, if I decline to present crude and immature thoughts to a Company that so well deserve the moist ripe ones, and can so skilfully discover those that are not so."

"I confess," saith Heliodorus, "that I think Pyrophilus's wariness deserve, not only to be allowed, but imitated; and therefore by my consent the further discourse of so abtruse a subject, shall be deferred till we have had time to consider seriously of Phoenomina that will be sure to imploy your most speculative thoughts, and I fear to pose them too: only we must not forget that Pyrophilus himself ought to be not barely allowed but invited to draw before we rise, what Corrollaries he thinks fit to propose from what he hath already delivered."

"The inference," saith Pyrophilus, "I meant to make, will not detain you long; having for the main been already intimated in what you may remember I told you I designed in the mention I was about to make of the now-recited Experiment. For without launching into difficult Speculations, or making use of disputable Hypotheses, it seems evident enough from the matter of Fact faithfully laid before you, that an Operation very near, if not altogether as strange as that which is called Projection, and in the difficultest points much of the same nature with it, may safely be admitted. For our Experiment plainly shews that Gold, though confessedly the most homogeneous, and least mutable of Metals, may be in a very short time (perhaps not amounting to minutes) exceedingly changed, both as to malleableness, colour, homogeneity, and (which is more) specifick Gravity; and all this by so very inconsiderable a Portion of injected Powder, that since the Gold that was wrought of weighed two of our English drams, and consequently an hundred and twenty grains, an easie computation will assure us that the Medicine did thus powerfully act, according to my estimate (which was the modestest) upon near a thousand times, (for 'twas above nine hundred and fifty) its weight of Gold, and according to my Assistants estimate, did (as they speak) go near upon twelve hundred; so that if it were fit to apply to this Anti-Elixir, (as I formerly vertured to call it) what is said of the true Elixir by divers of the Chymical Philosophers, who will have their virtue of their Stone increased in such a proportion, as that at first 'twill transmute but ten times its weight; after the next rotation an hundred times, and after the next to that a thousand, our Powder may in their language be stiled a Medicine of the third order."

"The computation," saith Aristander, "is very obvious, but the change of so great a Portion of Metal is so wonderful and unexampled, that I hope we shall among other things learn from it this lesson, That we ought not to be so forward as many men otherwise of great parts are wont to be, in prescribing narrow limits to the power of Nature and Art, and in condemning and deriding all those that pretend to, or believe, uncommon things in Chymistry, as either Cheats or Credulous. And therefore I hope, that though (at least in my opinion) it be very allowable to call Fables, Fables, and to detect and expose the Impostures or Deceits of ignorant or vain-glorious Pretenders to Cymical Mysteries, yet we shall not by too hasty and general censures of the sober and diligent Indigators of the Arcana of Chymisty, blemish (as much as in us lies) that excellent Art itself, and thereby disoblige the genuine Sons of it, and divert those that are indeed Possessors of noble Secrets, from vouchsafing to gratifie our Curiosity, as we see that one of them did Pyrophilus's, with the sight at least, of some of their highly instructive Rarities."

"I wholly approve," saith Heliodorus rising from his seat, "the discreet and seasonable mention made by Aristander."

"And I presume," subjoins Pyrophilus, "that it will not be the less liked, if I add, That I will allow the Company to believe that, as extraordinary, as I perceive most of you think the Phoenomena of the lately recited Experiment; yet I have not (because I must not do it) as yet acquainted you with the strangest Effect of our admirable Powder."