Notes on the first Title.

I. 1. THe Article mentions Ac­tual coldness and Heat, because we do not here consider that which the Schools call Poten­tial.

2. The knowledge of the degree of Coldness in the Water, especially if it be extraordinary, may somewhat assist the Examiner to guess, whether the Spring come from some notable depth under ground before it ascends, or whether it runs through a soyl abounding with Salt-Peter or Sal-ar­moniac, [Page 64] or some such very refrigerat­ing substance.

3. The degree of Coldness or Heat may be estimated several wayes as, if the Water be cold, by its having, or not having, the power to coagulate Essential Oyl of Anis seeds, or that of Fennell seed; & if it be that, by its be­ing, or not being, able to melt Bodies of somewhat differing dispositions to Fu­sion, as Butte, Tallow, Bees-was, &c. Or to coagulate the whites of Eggs, or to boyl Eggs in the Shell, &c. But the best way is to plunge into the Wa­ter propos'd, or least the whole Ball or globulous part of a good hermetical­ly seal'd Thermoscope, whereon the degrees of cold and heat are carefully mark'd.

Notes on the Second Title.

II. The knowledge of the specifick Gravity of a Mineral Water, may be of great use to him that endeavonrs to discover its nature, not only as this knowledge inables him to distinguish [Page 65] the propos'd Water from others, but because it may afford him a conside­rable and double information. For, by comparing the weight of the pro­pos'd Liquor with that of common Water, he may be, in case the former be heavier (as it usually happens to be) assisted to estimate what pro­portion of Salt, or Martial, or other Mineral Substance, it is impregnated with. And if it be very light, and much more if it be lighter than com­mon Water, he may probably con­clude that the Substance, that im­pregnates it, is either very small in quantity or proportion, or is not near so gross as is to be found in other Mineral Waters, but of a Spirituous and Volatile nature which is a disco­very of no small moment in this af­fair. And thó that may seem a para­dox which I here suppose, that a Wa­ter impregnated with a Metalline or Mineral Substance should be as light or even lighter than common Water. Yet upon Tryal carefully made I have found some Mineral Wa­ters, [Page 66] as particularly that of Tun­bridge well taken up, and (thô they be somewhat less light) that of the German Spaw, and of some of the Is­lington Springs, to be manifestly ligh­ter than common Water, and some taken up at Tun bridge I found to be lighter than common Water, even pu­rified by Distillation.

And thô it be very hard to con­ceive, yet I think it not impossible, that a Subterreneal Substance, that im­pregnates Water, should be lighter in Specie than it: but yet I would not re­fer this surprizing Levity, in all ca­ses, nor all of it in most cases, to the admixture of lighter Corpuscles, be­cause some Tryals justify'd the suspi­cion I had, that much of the Compa­rative Lightness proceeded from this, That the Mineral Water was imbued with a smaller quantity of vulgar or culinary Salt, than common Water uses to contain. But yet these Tryals did not satisfy me, that this paucity of common Salt was the sole or ade­quate cause of the lightness of the men­tioned Waters.

[Page 67] But, to discover such minute diffe­rences, one must have good Instru­ments, and indeed, to speak freely, there are few, upon whose Re­ports I durst confidently relye, for the Specific Gravity of Mineral Wa­ters. For to weigh Liquors any thing exactly there is requisite more Heed­fulness, and more Skill, and better In­struments, than are easy to be met with together, and than we usually imagine. And, when Physicians and others weigh Mineral Waters, they are wont to do it in some Apothecary or other Trades▪mans Shop, where, if the Ballances be small, the Vessels and the Water are commonly too heavy for them, and oftentimes wrong them. And if, as is usual, the Bottles or other vessels be great, they require far better Ballances than are usually imploy'd in the Shops of Apotheca­ries or Grocers, whose Ballances a Critical Examiner will too often find to be far from being accurate, inso­much that usually, without at all al­tering the weights, thô perhaps not [Page 68] great ones, he may easily make which Scale he pleases manifestly prepon­derate, and continue in that position, and may as easily afterwards give the other Scale the same advantage: The diligent and experienced Mathe­matician Mersennus much com­plains of the difficulty he found to weigh Liquors exactly, even by the help of his Nicer Instruments. The accuratest way, I know, is by com­paring the differing weights that the same sinking Body has in common Water, and in the Liquor propos'd. But this way (which I elsewhere circumstantially deliver) requiring, besides good Instruments, skill in Hydrostaticks, is practicable but by few. And the way of comparing Wa­ters, by the greater or lesser sinking of the same Cylinder or other swim­ing Body into them, is scarce accu­rate enough. Wherefore I chose to make a very skilfull Artist blow, at the flame of a great Lamp, a thin round vial with a flattish bottom, that it might stand upright, and be [Page 69] very light, and this was furnish'd with a neck as large as a Goose quil drawn very even into a hollow Cylinder of above 3 Inches long, and fitted at the top with a little Gap, that hinder'd the Water from ascending above the due height.

This Glass contain'd ℥iiiss and 43 grains of common Water, and yet when empty, weigh'd but ʒvi+ 42 grains: So that I could use it, when full of Liquor, in such a Ballance, that the addition or detraction of half a Grain, or less, would make either Scale preponderate. The length and evenness of the stem was design'd for uses not needful to be mention'd here; where it may suffice for my purpose to say, that this Glass was judged capable of holding Water enough for not uncurious Tryals, and yet not to be, thô well fill'd, too heavy for a tender Ballance. In this Vessel herefore we carefully weighed several Liquors (whose Gravity be­longs not to this place) and among them diverse Mineral Waters, some [Page 70] of which, at least known here at Lon­don, were found to be of the annex­ed weights.

The Glass being fill'd with several Liquors to the same height, and weighed in the same Ballances.

By this short account it may ap­pear, that, as divers Mineral Waters (that contain Salts in them) are con­siderably heavier than Common Wa­ter, [Page 71] so some, especially Ferruginous Waters, are impregnated with so fine a substance, as to be lighter than com­mon Water.

Notes on the Fourth Title.

IV. This Article may, in divers ca­ses, give some light to the discovery of the kind of Soyl, through which the Water has pass'd; and is also useful to distinguish the Spontaneous resi­dence, if I may so call it, that the Li­quor lets fall by meer standing, from that which they call the Caput Mor­tuum, that remains after the total eva­poration of the Water; by which means also the weight of this last re­sidence may be more truly known. Besides some other Mineral Waters, I found that the German Spaw Waters, brought very well stop't to London, afforded by long standing a pretty quantity of Terrestrial substance, that look'd almost like yellow Oke [...], and perhaps was of great affinity to it in nature. 3. That clause in the Article, [Page 72] thô the Liquor be kept from the Air, was therefore set down, because I had found by Tryals, that some Liquors, by being expos'd to the free Air, would have copious, and sometimes surprizing, substances separated from them; as if the Air contain'd some Precipitating Salts, fit to work on the Liquors, so as to make in them such notable separations.

Notes on the Fifth Title.

V. An accidental weakness I had, in my eyes, when I had the best oppor­tunity to endeavour satisfying my self about this Inquiry, forc'd me to leave the prosecution of it to others. Only two things I shall take notice of on this occasion: One is that, having caus'd one that had young Eyes, and was accustom'd to make use of such Microscopes as are mention'd in the Article, to look upon some Mineral Waters through them, he said he could discern no difference between them and common Water. Notwithstand­ing [Page 73] which the Tryal ought to be re­peated by various persons, on several Waters, with differing Engyscopes, and in differing Lights, and other circumstances. The other is, that whereas it is by divers learned men objected, against the goodness of these magnifying Glasses we now make use of to look on Liquors, that the little Bodies that the ingenious, Mr. Lewenhoeck, and since him di­vers other Virtuosi, have observ'd in Water wherein Pepper has been in­fus'd, are not, as he pretends, living creatures, but little inanimate con­cretions, that are casually form'd, and carry'd to and fro in the Liquor: To convince these Doubters, of whose number I was my self at first inclin'd to be, I devis'd the following expe­riment: Having laid, upon the magni­fying Glass, a part of a drop of Wa­ter, wherein I could see store of these little Animals frisking up and down, we put to the Liquor, with a bristle or some such very slender thing, part of a drop of Spirit of Salt, which, as [Page 74] was expected, presently kill'd these little tender creatures, and depriving them of their Animal Motion, left them to be carry'd so slowly to and fro in the Liquor, as to make it visi­ble that they were then dead and had been before alive.

Notes on the Seventh Title.

VII 1. The Odours of divers Mi­neral Waters are best judg'd of at the Spring head or other Recepta­cle, whence some of them being remov'd scarce afford any O­dour at all (perceptible by us men.)

2. Perhaps the Sulphureous scent, that is sometimes, perceiv'd in Tun­bridge and some other Waters in their sources, may in part proceed from loose Exhalations, that casually hap­pen to be mingled with the Waters, but do not constantly belong to it.

3. The winy odour is mention'd among others: Because I am credibly [Page 75] inform'd that, in France, there is a Mineral Spring, if not more or less than one, that has such a smell.

4. I mention the Bituminous O­dour, distinctly from the Sulphureous because men are too apt to confound them, and take all stinking Mineral▪ Waters for Sulphureous, whereas di­vers are manifestly Bituminous; as may be gather'd, to omit other signs, not only from their proper odours, but from more or fewer drops of Petro­leum, or a kind of course Naphtha, that are found swimming upon the Water.

5. I think it also not unlikely, that sometimes a Spring may partake both of Sulphur and Bitumen, min­gl'd together by the Subterraneal Heat, since I have found that I could easily enough melt and incorpo­rate these two substances here above ground.

Notes on Ninth Title.

IX. 1. This is an almost necessa­ry Article because many Persons, that drink Mineral Waters, cannot well, either for want of strength or conve­niency, repair immediately to the Spring head, but are oblig'd to drink them in their Beds or their Lodgings, and perhaps to have them transport­ed to a great distance, or even to ano­ther country. 2. Many Purging Wa­ters are found to retain their Laxa­tive vertue, and that perhaps for a considerable time, thô they be tran­sported to places distant from those they rise in. 3. In such Ferruginous Waters, as are lighter than common Water, I found a manifest difference in reference to transportation: For most of them, even such as will bear re­moving, have something of freshness and quickness at the Spring head, (perhaps from some Spirituous and Fugitive Exhalations, that there arise with them, but presently vanish,) that [Page 77] they have not any where else. And some do not only lose this briskness by being remov'd, thô in vessels well stop'd, but they lose also the power of producing, with the powder of Galls, a Purple colour, as I found by Tryal purposely made in more than one of these Mineral Waters, which, to prevent fraud, I sent for to the Springs themselves by servants of my own: For thô these carryed their Glass Bottles along with them, and had no other Errand there but to fill and stop them carefully yet, by being transported less than one league, I found them so alter'd, that they would no longer make a Purplish co­lour with powder'd Galls, but a deep reddish one; whereas the German Spaw Waters did almost alwayes here in London afford me, with the same Powder of Galls, a rich Purple Co­lour. And Tunbridge Waters afford­ed me the like, but not so deep a one. when I receiv'd them at London very well stopt. 4. This last clause was not to be omitted, because the exact [Page 78] or negligent closing of the vessels, wherein such Waters are transported, is a circumstance of great moment. For more than once I receiv'd at Lon­don, Waters sent me from Tunbridge by Physicians themselves, (who us'd at least a moderate care in putting them up,) which yet would by no means afford with Galls a purplish Colour. And I found that even the German Spaw-Water would almost presently lose its capacity of being made Pur­ple by Galls, if it were considerably heated. 5. But the same Spaw-Water being, in Summer time, kept all night in an open Vessel, did the next morning till it was late, if not till Noon, retain a dis­position to be made Purple by the admixture of Galls; but that dispositi­on it lost before the next day.

Notes on the Fifteenth Title.

XV. 1. Because it often happens, that men have not the leisure and the conveniency totally to evaporate the proposed Mineral Water, it may be an useful thing, to be able without e­vaporation to discover, whether it contain any common Salt and, if it do, to make some estimate, how copious­ly or sparingly the Liquor is impreg­nated with it. This might easily be done, with nicety enough, if I were not by very just Reasons restrain'd, for a while, from communicating that way of examining the saltness and freshness of Waters, of which I did, by the Kings command, show his Ma­jesty some proofs, whereof mention was presently after made in the print­ed Gazets. But till it be free for me to impart that way to the publick, I shall only intimate, that some guess may be made at the Saltness of Wa­ters, by observing, whether they will lather with wash-balls or Soap, [Page 80] and, if they will not, what quantity of curdled matter they will produce; as also, whether the Waters will serve for washing of Linnen, and will boil Peas tender? Which two are the most usual wayes that many Sea men take to examine the goodness of unknown Waters by. In divers Purging Wa­ters this way may be difficult to be practis'd with certainty, because of o­ther Salts that may be predominant in them; but in the Examen of light­ly Ferruginous Springs it may be more rely'd upon. 2. It may not be unworthy observation that, when I made use of my own way of exami­ning the Saltness of Mineral Springs, I did not find even the lightest sort of them devoid of common Salt; which I found, but not in equal pro­portions, to be contain'd, not only in the several Waters of Islington, Ham­stead VVater, and, if I misremember not, in some others, but also particu­larly in Tunbridge VVaters, and those of the German-Spaw, which I did not much wonder at, because I had long [Page 81] known, that more or less of common Salt is very usually harbour'd, thô not observed, in many Soils, through which all sorts of Springs, and con­sequently Mineral ones, have their course.

Notes on the Sixteenth Title.

XVI. Thô Acidity be so usually a manifest Quality of Mineral Waters, that Authors are wont to divide them into Acidulae and Thermae, yet I have found, by several Tryals, that 'tis not near so easy as men presume, to find a manifest Acidity in all Mineral Waters, that are not Sulphureous or Hot. For several Ferruginous Wa­ters, having probably spent the Aci­dity they had upon the Iron Ore, which they dissolv'd in their passage, retain so little Acidity, that 'tis hard to discover they have any, either by their working upon Coral, or by any conflict with Spirit of Urine, or the like, or by mixing them with Syrup of Violets, to change the colour of it; [Page 82] insomuch that sometimes I should have concluded some such Waters to have no Acidity at all, if I had not had a way of discovering a far less degree of it, than I could discern it to have by other Tryals. The circumstances, that made this way of examining so critical, will cost me too many words to set down here, and I have done it in another Paper expresly written, of the way of discovering the Quali­ties of divers Bodies, by changes of colour made in or with them: And therefore I shall here but briefly tell you, that I discover the Acidity of Liquors by their operation upon the colours of an Infusion of Lignum Ne­phriticum made in Lympid Water, (and order'd after a certain manner.) By this means I found the German Spaw Water to retain a little Acidity, even here at London; but more than one of our own Ferruginous Springs did not, even upon this Tryal, appear to have any. And (which some may think strange) I did not find even some of the Purging Springs, particu­larly [Page 83] that of Acton, to have any discer­nible Acidity.

Notes on the Twentieth Title.

XX. The Scope of this Inquiry was twofold: The first, to discover whether a change of Texture would notably alter the Qualities of the Li­quor, when the Hermetical Seal hin­der'd the Avolation of any Saline, Ferruginous, or Spirituous parts: And the other was, to see whether such an Agitation, by heat, as in the open Air would, as I had found, deprive the Spaw Water of the vertue of making a Purple colour with Galls, would cause any manifest separation of parts in the Liquor, and make any grosser substance to precipitate or subside. But thô we did twice (not without difficulty) make the experiment with Spaw Water, yet we made it without success. For the first time the Glass broke at the bottom, before the Wa­ter we immers'd it in was near boyling hot. And thô the other Glass resist­ed [Page 84] longer, and indur'd a greater heat, yet in not very many Minutes that also broke at the bottom. Which disap­pointments a faithful Historian ought as little to conceal, as better successes. And I chuse to leave this 20th Arti­cle of Inquiry in its place, among the rest of the Titles, because possibly some other may be more happy, than I was, in endeavouring to answer it. And I hold it not amiss, in drawing up Platforms of Natural History, to set down what Questions we think fit to be propos'd to nature; because we cannot be sure, before Endea­vours for Tryal be us'd, whether the thing to be attempted be practically performable or not.

Notes on the Twenty sixth Title.

XXVI. 1. Divers wayes may be propounded to discover which of the Qualities, mention'd in this Arti­cle, is predominant in the Salt to be examin'd; but I confess I somewhat doubt, whether these waies of Tryal be so certain, as many will be forward to think them. 2. If Acidity be guess'd to be predominant in the Salt propos'd it will probably appear by such waies as these. By the Tast, odour, or both: By working upon Coral or Crabs eyes finely powder'd: By curdling of Milk; By making Syrup of violets reddish: By the power of destroying the blew colour of the Infusion of Lignum Nephriticum: By not being Precipita­ble by Potent Acid Liquors as Oyl of Vitriol, Spirit of Salt; and by being Precipitable by Oyl of Tartar per de­liquium, as also by strong Spirit of Urine, and other volatile Alcaly's, as they are call'd. But, as I was noting above, I doubt whether these proofs be [Page 86] absolutely certain; for, if I mistake not, I found some Purging Mineral Waters that would not give even so slight a proof of acidity, as to destroy the blewness of the Nephritic Tin­cture: Which yet would curdle Milk, and turn it to a kind of Posset; and, on the contrary, I found that some Ger­man Spaw Water would not curdle Milk, & yet would readily deprive the newly mention'd Tincture of its ce­ruleous colour; which yet I did not find that some of our English Fer­ruginous Waters were, at least when brought me to London, able to do. 3. The predominancy of an Alcaly, in the Salt of a Mineral Water, may be probably discover'd by such waies as these. By the Lixiviate Tast, Smell, or both; the former of which may be observ'd in the true Niter of the Ancients, (which I have had brought me from Aegypt, and a neighbouring Country, whose name I do not now remember:) By the turning of Sy­rup of violets green: By the Precipi­tation [Page 87] of solution of sublimate made in Spring-Water: By an effervescence or conflict with some potent Acid, as Aqua fortis, or well dephlegm'd Sp­rit of Salt: By heightning the red Tincture of Logwood or Brazil, drawn with common Water, to which, may be added a Nicer way or two that I have elsewhere mention'd. But I propose these waies but as ap­pearing rational, upon the score of my having successfully try'd them with other Saline Bodies that were Alca­lisate. For as to those Mineral Wa­ters, I have had occasion to examine, I do not remember I have yet met with any, wherein an Alcaly was pre­dominant. 4. But perhaps farther Inquiry will discover to others here in England, what I have not yet met with: And I doubt not but that there are, in divers places of the Earth, Salts of an Alcalisate nature. And I pre­sume that, if the Egyptians were any thing curious of such things, they would find, among their Springs or Wells, divers Waters impregnated [Page 88] with them. For I found by Tryals, purposely made upon Latron, as some knowing men call the true Egyptian Niter, presented me by an inquisitive Ambassador who came out of the East, that the native Salt exhibited di­vers of the same Phaenomena that other factitious Alcali's do. And some Salt, afforded by the famous Waters of Bourbon in France, being brought me thence, with a desire that I would examine it, I found it to be evidently Alcalisate; insomuch that it would make a conflict with Acids, and pre­sently turn Syrup of violets green. 5. If we suspect Vitriol to be much predominant in the Saline part of a Mineral Water, we may endeavour to discover it by such wayes as these. By its blackning a Solution of Galls: By its vomitive operation upon the Drinkers, thô this may sometimes be an uncertain way especially because an invisible permixture of Arsenic, or or perhaps Arsenical Fumes, may give the Water they impregnate an Emetic Quality: By putting Alcali's [Page 89] to a strong solution of the suppos'd Vitriol, and observing whether it will afford a yellow or yellowish Precipi­tate, if Salt of Tartar or Spirit of Urine be dropt into it. By taking notice, whether a Sulphureous Spirit, espe­cially▪ such an one as I formerly told I had made thô not here describ'd, will make a blackish or a very dark colour with it, as I first guess'd, and then found it would do with several vitriolate Liquors, and even with one, to make which we had dissolv'd but one grain of a Natural Vitriolate sub­stance in above four or five thousand times its weight of Syrup or Water. But in the parts about London I re­member not that, in any of the Waters I have made Tryals on, I have found Vitriol to be predominant, or to be so much as a manifest Ingredient: Which seem'd to me the more re­markable, because several parts about this City are not destitute of Marca­sites, the Parents or Wombs of Vitriol. Since the writing of these Papers, being casually visited by a discerning [Page 90] Stranger, who had a particular occa­sion to take notice of the Residences of many of the Mineral Waters of France, his native Country; he an­swer'd me that he never met with any that was manifestly Vitriolate; and he seem'd to be of opinion, that no Vi­triolate Spring had yet been disco­ver'd, among the many Mineral ones that are known to be in that Country. 7. Since we so rarely meet with either manifestly Acid, or evidently Alcalisate, Salts in our English Mine­ral Waters, it may deserve a serious Inquiry, what other Salts they may be impregnated with; and especially from what Salts, the Purgative ver­tue, that is found to belong to many of them, as Epsom, Barnet, Acton, &c. do's proceed? Common Salt indeed, as is already noted, I have found to­kens of in the German Spaw Water; and in all the English Mineral Waters, I had occasion to try, not one that I remember excepted. But I did not find that common Salt was so copi­ous in any of them, as to disclose it [Page 91] self by Chrystallizing in Cubical grains. And the way, I made use of, to examine the Saltness of the Water without Crystallization, is not equal­ly certain in all sorts of them. And because I had not store enough of these Liquors, to evaporate them in large quantities, thô I could not discern, in the clear Salts they afforded, either Vitriol, or Salt Peter, or Allom, or even common Salt, by their peculiar and genuine Figures; yet I dare not confidently say, that none of our Eng­lish Mineral Springs abounds with any of those Salts. But as far as I can guess, by the Tryals that I have hitherto had opportunity to make, I am apt to think that the Salt, that is found in our Purgative Waters, and and in some of them copiously e­nough, dos not belong to any one known sort of Salts, but is either of a sort, for which as for many other Minerals, we have yet no name: or, which seems more probable, is a Salt of a compounded Nature, made up by the coalitions of some or all of [Page 92] the Salts above mention'd, and per­haps of some other, as yet nameless, Subterraneal Salt that the Spring inssolves in its passage, That two Bodies, which are neither of them Cathartic, may, by a change of Tex­ture, wrought in one another, com­pose a third Body, that is briskly purgative, I have shewn in another Paper. Besides having formerly had occasion, in order to the resolution of a certain doubt I had entertain'd, to burn Salt of Tartar with about a double weight of common Sulphur, I thence obtain'd, as I expected, a Neutral Salt, that had peculiar Qua­lities differing from those of the Bo­dies imploy'd to make it up: And talking of this Salt with an ingenious Empyrick, he told me it had a Qua­lity I had not mention'd, and that a very useful one, since in the dose of half a dram, or in some Bodies, being taken in Wine or Broth, it would con­siderably, and yet gently and without gripings, purge. And without the help of Salt of Tartar have sometimes [Page 93] made out of common Sulphur, a Chrystalline Salt of a somewhat Vi­triolate Tast, the like to which might possibly be made under ground, where there are Subterraneal fires, tho per­haps not observed nor suspected, since we made this Salt without adding any thing to the Sulphur, on­ly by the help of Fire and common Water. And I remember that a great Virtuoso, several years ago, brought me, in order to an Examen he desir'd I should make of it, a certain Salt af­forded by a Spring in or near his land, which I remember was in the West of England, tho I have forgot the name of the County: Which Salt no Body knew what to make of, but I quickly told him, I took it to be of the na­ture of the Sal mirabile Glauberi, and predicted that in such Tryals it would afford such and such Phaenomena, which accordingly came to pass. And I thought that, if opportunity had not been wanting this Salt would have appear'd Purgative, as some factitious Salts that resemble it in [Page 94] transparency, colourlesness, and Fi­gure have been observ'd to be.

Notes on the Twenty seventh Title.

1. 'Tis surprizing to observe, how great an inequality one may some­times meet with in the proportion that the same quantity, of two▪ differ­ing Mineral Waters, bear to the Ca­put Mortuum they respectively afford: For a pound, for instance, of one may, after evaporation, leave behind it perhaps more drams of dry substance, than a pound of the other will leave behind it grains. But because I have no notes of the considerablest Instan­ces of this kind, that came to my knowledge, I shall add only by and by the Product of a more recent Tryal. 2. As far as I have hitherto observ'd, those Ferruginous Waters, that are not heavier than common Water, and in most Drinkers prove but diuretick, afford but very little Caput Mortuum, or dry Substance up­on the total Evaporation of the Li­quor, [Page 95] whereas Mineral Waters, that are purging and manifestly more ponderous in Specie than common Water, leave, upon Evaporation, a con­siderable quantity of residence, thô some far less than others. 3. At once to explain, and partly prove, what I have been saying, I shall here recite that, from a pound of Barnet VVater (which is known to be pur­gative) slowly evaporated, we ob­tain'd a Dram of VVhite Powder. But from the like quantity of Tun­bridge VVater, we obtain'd but about one grain of Caput Mortuum: And, if I misremember not, we had but about a grain and a half from 25. Ounces of the German Spaw Water. 4. It may seem scarce credible to many, that so small a quantity of matter, of which perhaps not one half is Saline, or Metalline, (the rest being teres­strial,) should impart a manifest ver­tue to so great a proportion of VVa­ter. But this difficulty did not much trouble me, who have purposely made divers Experiments, to discover how [Page 96] small a proportion of Mineral matter may suffice, when dissolv'd, to im­pregnate common VVater. I remem­ber I took one grain of Iron stone, casually found near the Springs at Islington, (from which Mineral 'tis probable those VVaters derive their vertue,) this being open'd by the fire, and dissolv'd as far as it would be in a little Spirit of Salt, we let fall a drop or two of the yellowish solution into a great proportion of Infusion of Galls, to which it presently gave a deeper colour than Tunbridge Water, or even the German Spaw VVater, was wont to give here at London, with the Powder of Galls: So that we guess'd that, if we had then had at hand a competent quantity of the in­fusion, the remaining part of the Martial Solution would have been able to colour ten times a greater quantity of the Infusion, than our Tryal was made upon. This will be easily believ'd by him, that shall consider an Experiment, we afterwards made to the same purpose, [Page 97] which was this, VVe dissolv'd a half grain of a good Marcasite, taken up not far from London, in a small quan­tity of Spirit of Niter, (which for a certain Reason I made choice of, thô other Acid Menstruums, as Aqua­fortis, and Spirit of Salt would have dissolved the Mineral.) This small solution we put into a pound of pret­ty high Tincture of Galls, made by infu­sing them in common Water, and finding, as we expected, that this mixture, grew very dark, we fill'd a Vial with it, and emptying that Vial into a larger Glass, we fill'd the same Vial three times with common Wa­ter to dilute it; notwithstanding which this new mixture, being put into one of our usual Glasses, appear­ed of a colour much deeper than that which the Water of Tunbridge, or the German Spaw, had formerly given with the Powder of Galls: So that pro­bably, if another Vial of common Water had been added, it would yet have afforded a purple colour, if not a dee­per; so that one part of dissolv'd Mar­casite [Page 98] communicated a Tincture to (61440) sixty one thousand four hundred and forty parts of Infusion of Galls. And that which makes this Experiment more considerable is, that this small quantity of Marca­site was not it self all Martial or Me­talline: For from our English Marca­sites, as well as others, I have ob­tain'd a pretty quantity of Sulphur like common Sulphur; besides that they afford a not despicable quantity of Terrestrial Substance, about whose nature I have not yet satisfy'd my self. 5. I shall now add this reflexi­on that, since the Marcasite impreg­nated so much Water with its corpo­real Parts, if I may so call them, ob­tain'd by bare dissolution, it seems highly probable, that the same quan­tity of Liquor may be impregnated by a far less quantity of Mineral mat­ter, attenuated into a kind of Spiri­tuous slate, by being rais'd in the form of Fumes or exhalations; and that imperfect or embryonated Iron may be so, will scarce be deny'd by [Page 99] them that consider the way that I have, in another Paper, deliver'd to make Iron manifestly emit copious Fumes, without the help of external Fire. And if it be with some such Spi­rituous and volatile Exhalations, that a Mineral Water, as that of Tunbridge or of Islington, is impregnated, 'tis not hard to conceive that they may easily lose their chief vertue, by the avolation of most or many of their fugitive Parts, upon their being re­mov'd to a distance from the Spring head. And to make it probable, that vitriolate Corpuscles may be made to ascend, without losing their na­ture, I shall here mention an Experi­ment, that I devis'd to give some light in this matter. I had often found by Tryal, that a Spirit, richly impreg­nated with volatiliz'd Sulphur, would with vitriol, whether in the form of a powder or a solution, produce in a trice a very dark or blackish colour; And guessing that, in Mercury turn'd by the addition of Salt and Vitriol into corrosive sublimate, many of the Vi­triolate [Page 100] Corpuscles might ascend with the Mercurial ones, I took such a Vo­latile Sulphureous Tincture as I have been mentioning, (which for this purpose ought to be deep,) and hav­ing dropt it upon good Sublimate, I found it turn presently of a very o­pacous colour. To show also that, to make a great dilatation or dispersion of the Martial Corpuscles of an Ore or Mineral, there needs no Spirit of Salt, or the like distill'd Menstruum, I procur'd from a copperas-work, (or place where vitriol is made by art,) some of the Liquor they imploy, be­fore they cast in Iron, that being cor­roded by it, it may increase the weight, and give solidity and some other Qualities to the designed Vitri­ol. Now thó this Liquor be made, without any Chymical Menstruum, barely by Rain or Snow-Water, that impregnates it self with Saline or Me­talline Particles in its passage through Beds of Marcasites, that lye expos'd to the Sun and Air; yet in this Wa­ter such numbers of Martial Corpus­cles [Page 101] are dispers'd that, having shaken four drops of it into 12 Ounces and a half of common Water, this Liquor, as I expected, was thereby so im­pregnated, that with powder of Galls it presently produc'd as deep a colour as good Tunbridge Water would have done. So that, supposing a drop of this Liquor to weigh about a grain, (as by some Tryals purposely made we found it to do,) it appears that one part of the vitriolate Water was able manifestly to impregnate 1500 Parts of common water. And yet of these 4 drops or Grains of Vitriolate Liquor, a considerable part may very probably be concluded, from the way of its production, to have been Rain Water, as will easily be granted when I shall have added, that, to exa­mine this supposition or conjecture, we slowly evaporated some Ounces of the Vitriolate Liquor, and found that the remaining dry Substance did not fully amount to the 4th part of the weight of the whole. At which rate 'twas easy to conclude, that one [Page 102] grain of Vitriolate substance would have been sound capable of so impreg­nating six thousand times its weight of common Water, as to make it sit to produce with Galls a purple tincture. We afterwards found, upon Tryal pur­posely and warily made, that the experiment will hold, thô the pro­portion of the Water, to the grain of tinging substance, should exceed that lately mention'd, by the weight of some hundreds of grains.