An Account of Some Experiments Made at Several Meetings of the Royal Society by the Ingenious Fred. Slare M. D. Fellow of the Royal Society, and One of the Colledge of Physitians, with Some Short Applications of Them to Physical Matters

An Account of some Experiments made at several Meetings of the Royal Society by the Ingenious Fred. Slare M. D. Fellow of the Royal Society, and one of the Colledge of Physicians, with some short applications of them to Physical matters. Experiment I. A Parallel betwixt Lightning and a Phosphorus. 1. In order to the keeping my solid Phosphorus from consuming, I usually plac'd it at the bottom of a Glass of Water: having several of these Glasses disposed upon a Table in view whilst I lay upon my Bed, I could observe several flashes of Light that successively past through the Water, and made such bright, and vigorous Coruscations in the Air, as would surprize and affrighten one not used to the Phenomenon. This fiery Meteor passes something contracted through the incumbent Water, but expands itself much as soon as it gets above it. If you would make these Experiments to advantage, the Glass ought to be deep and Cylindrical, and not above Three-quarters fill'd with water. If we compare these appearances with Lightning, we may observe that Lightning, which comes at Intervals passes uninterrupted the most condensed Clouds, and is not extinguished or obstructed by the greatest Storms or Cataracts of water, but like the Beams of the Sun or any other fire freely passes through Glass and water. 2. This Phosphorus in the mentioned state only emits these Flashes of Light in warm weather, a certain temper of the Air being necessary to produce the effect, for in the Winter or cold weather I never observed it. The warm season of the Summer is most productive of Lightning. 3. The mention'd Flash of Light is not apt to kindle or burn any combustible matter, as I found by holding my finger in it unmolested, but not trusting to that, I held in the flame, Paper, Flax, and such Materials as are apt to take fire, which it did no more than when we projected the Light of the Moon by a Concave Glass, upon the like bodies. Such an inoffensive Flame that of Lightning is generally observed to be. But 4. The matter of the Phosphorus, whilst in a more condensed body, will easily be accended by the warmth of the Air, or by the immediate Beams of the Sun, and then will burn very furiously with such a penetrating fire as will not easily be extinguished. Thus Lightning; when condensed or contracted, and wrapt up in a Vehicle of Air, so that it does not so easily diffuse itself through the yielding Aether; will then set fire to Houses, Trees, &c., and do great mischief. 5. Our matter whilst burning acts the part of Corrosive, and when it goes out it resolves into a Menstruum that dissolves Gold, Iron, and other Metals. Thus Lightning melts down, Gold, Iron, Lead, and other Metals. These Experiments were concluded most Naturally to illustrate illustrate and resemble the *Phenomena* of Lightning, far exceeding either those made with Nitre, Gun-powder or Aurum fulminans. As to some other properties of this shining and burning Preparation see the Philosophical Collections. **Experiment II.** By mixing Two Liquors actually cold to produce such sparkling and fiery bodies, as are not only visible in the dark, but at noon day in the enlightened Air. This Experiment was not a little surprizing, which was thus made. We took betwixt Ten and Twenty Grains of the solid Phosphorus and caused it to melt in as much water as would just cover it, which was about a Dram: after it was actually cold we poured it into two Ounces of Oyl of Vitriol, which being well shaken together did first heat, and then throw up such fiery Balls, which like so many Stars will adhere to the sides of the Glass and continue to burn for some time to the great pleasure of the spectator. **Experiment III.** By the addition of an Oyl to the foregoing mixture to produce a flame. This is done only by pouring a small quantity of Oyl of Turpentine, without shaking the Vessel, the mixture takes fire and burns very furiously. This Experiment ought to be made in an open Vessel where the Air has a free access. This succeeded with Oyl of Petroleum, and de Larteribus: but Sallet-oyl and spirit of Wine would not be made to flame. The Ingredients that compose this burning mixture are apart cold to the touch, and some of them in their operations perations, thus Water and Oyl of Vitriol are cooling in their Nature, but these in Conjunction cause a great heat, which soon excite the agile Particles of our Phosphorus to an actual fire, and this Meeting with an inflamable Ingredient such as Oyl of Turpentine, or the like; does produce as considerable a flame as boiling Oyles as wont to do. These Experiments would have been less considerable or surprizing, had that of Borrichius been certain mention'd by Bartholinus in the Acta Hafniensia) and quoted by an Ingenious Fellow of the Royal Society as credible. The Title of the Experiment being, to make two Liquors kindle one another tho apart they are actually cold. Tho I knew it would fail of the desired event by several unsuccessful Tryals I had made, yet I was the willinger to make the Experiment before so many impartial Judges, because this specious Experiment had been imposed not only on some that were present, but also on the faith of many of the German Nation, who sometimes quoted it to serve their Hypothesis. This made it necessary to bring it to a final Determination. Experiment IIII. Being a Refutation of Borrichius's Experiment that pretends to Accension. We took according to direction four Ounces of fresh drawn Spirit of Venus Turpentine to six Ounces of Aquafortis newly drawn and very strong. We mixed them together in a Glass body, and accordingly placed the Vessel in the Sun Beams, (which I foretold some of the By-standers would deceive us) after half an hours Patience the Liquors began to ferment very furiously, insomuch that a very great Smoak was raised by this means which was ordered to kept down by a Cork that stopt the the Vessel. This condensed red Fume represented flame by by reason of the Beams of the Sun that were permitted to shine upon it; but I was assured that this was a great Fallacy, and that the Experiment contradicted the Proverb, There is no Smoak without some Fire. I was willing to give the Experiment any advantage, which made me comply with that Circumstance of doing it where the Beams of the Sun were admitted; but this very Circumstance giving ground to the mistake, I desired leave to make the Experiment in a dark Room where we should better discern any real productions of Light: being assured that the action of the Liquors would as certainly succeed in the darken'd Room as in a light One. The Experiment was repeated, and the action of the Liquors was no less vigorous than in the former Experiment. Moreover Flax, being lookt upon as a very combustible matter, was suspended in the Fume: but in short, the Observers of this Experiment, which were many and very Inquisitive, could not discover the least spark of fire or glimpse of Light, so that the Flax remain'd untouched, and the fermenting Liquors gave no light, fire, or flame: only take this Caution; keep your Candles at a distance, for the Fume will soon take fire at any actual flame and set the Liquors a burning, and so it may impose upon the Careless. Experiment V. Being a New Experiment with Ebullition and incalescence. Amongst those various mixtures, wherein great Heats and Effervencies with much Ebullition were produced, none were so considerable as this, which was also shewn at the same Meeting. Upon an Ounce of spirit of Nitre, if you pour two or three Drams gradually of the highest rectified Spirit of Wine, the Heat and Ebullition will be incredibly great. And whereas in the former Experiment you must wait a good time for your Effervescence, here tis performed in an instant so that I had more reason to expect from the mighty action of these Liquors upon each other, a production of actual fire or flame, than from Borrichius his Experiment. Possibly some may be ready to imitate this Experiment which may fail them, unless they observe some little Directions. Errors of this kind have made some people believe they are imposed upon when there is no such thing. Common Spirit of Nitre, such as was first distill'd into water, and afterwards dephlegm'd (or distill'd so as to have all the water separated) this will fail your expectations; it must be the Red Spirit of Nitre, and a very high rectified Spirit of Wine. In the next place, you must first pour into your Glass the spirit of Nitre, which is the heavier Liquor, and then the spirit of Wine after, for if you invert the order you will have no Ebullition, which will not a little puzzle the reason of Philosophers. In this Experiment (especially if the Ingredients are made very high) the Spirit of Nitre does as it were act the part of a Coal of fire: as fire exhales and drives up water that is thrown upon it, so does this Spirit of Nitre very furiously throw up a great quantity of the Vinous spirit, in so much that it presently perfumes a Room with the smell: but to be more exact in this Observation, we mix'd equal parts together in a Retort, and then cemented a Receiver of good dimensions, and so we condens'd that Vapor which rises from this mixture and obtained much of our Spirit of Wine again. Both these Experiments may serve as Arguments against the notion of Acidum and Alkali, since mighty Conflicts may be excited by bodies of differing Textures where these two Principles are not conspicuous. We have here indeed very strong Acids, but in the other never were any Alkali's suspected whether volatile or fixt. Nor can I think that that latent Alkali imagined to be in the spirit of Nitre does produce duce this great conflict, for I question whether there be any such thing; if it be an Alkali, it has quite lost its property, that is not wrought upon by so strong an Acid in whole bosom it lies. Wood may as well remain combustible in a great Fire, as such an Alkali under the power of so great an Acid. But this is only a hint. There are various Liquors whose mixtures are apt to produce greater or lesser effervescencies, heats, and inflammations, so that particularly the great Incalescence and burnings in Fevers are easily accounted for, and made obvious by occurring Experiments. There seems more difficulty to account for some cold disaffections of the Blood, and other Juices of the body. For Hysterical Persons will complain of a great Chilness or Frost in the Blood, during that Paroxysm, such as a good fire and warm Cordials will not easily conquer. In these Persons the Pulse is always very tardy, (differing from what I have observed in Agues where in the Cold Fit it has been very quick.) This may be better explicated by a solution of Sal Armoniack than of Nitre in water. Experiment VI. Of Cold produced without Ebullition, giving some account of Hysterical Paroxysms. In about a Pint of water we dissolved a Quarter of a Pound of Sal Armoniack, which was found to be so very cold to the Touch that we needed no Weather Glass to convince us of the effect. In this Experiment we have no Ebullition or Swelling of the Liquors; but rather a condensation, which may also happen in the Hysterical frigid Paroxysm, for in case the humours swell'd they would require more space, which perhaps is not to be allow'd, but must then be compensated by the acceleration of the Pulse, which would then be be obliged to transmit the extended humours in a shorter time, but this is not our case here, but refers to the next. I here choose to explain the affections of the blood by the solution of Sal Armoniack that (as we said) in our Experiment affected the Blood of those Persons that long touched it, with a sensible and troublesome degree of cold. For the Mass of Blood may be very apt to degenerate into such Concretions as do much resemble Sal Armoniack; and this will seem more probable if we consider that humane and other blood naturally abounds with Urinous Salts, and do preternaturally degenerate into Acrimonious and Pungent Juices, which may be much promoted by a too liberal use of high season'd or salted Meat, and sour Liquors. For this we find by Experience that such an acid as Spirit of Salt mixing with an Urinous, will be converted into sal Armoniack (which has now lost much of its Volatile Nature). This we may plainly discern by its shooting into a Figure, that resembles Feathers, which is proper to Sal Armoniack. That the blood does abound with various sorts of Salt 'tis not to be doubted, and that it has such a Salt as some call Salsum, which is sea-salt, I lately exhibited at the Royal Society, and lastly that Sal Armoniack has its principal dependance on great quantities of Volatile salt (such as the blood is stored with) and on this mention'd Salt, 'tis very well known. So that having presupposed such Concretions as these to have their existence in the blood, we must consider how they come to act. That there may be some antecedent and other Concomitant Causes of Hysterical Passions, I do not deny; I only or principally consider the cause of the cold affections. 'Tis very probable that the Glands do suffer great obstructions, which are antecedent to this Paroxysm: I am the rather inclined to this opinion, by reason of so great a Thirst our Patients are apt to complain of before and in the Fit: by which obstructions the usual Secretions of the Lympha are hindred as well from watering the the Mouth as the Oesophagus and Stomack, which causes Thirst. Moreover the less quantity of Lympha is evacuated the usual way, the more is absorbed by the Veins, which does so dilute those Salts in the Mass of blood as brings them to a Fluor or such Solution as is necessary to give the cold Effect. Thus sal Armoniack will mix with some Liquors and not with others, scarce at all with Spirit of Wine, and not so well with Wine as Water, and the more limpid the Water is, the better and sooner it dissolves, and to this Menstruum does especially impart this cold Operation. Which not unreasonable conjecture of an extraordinary effusion of Lympha into the Mass of Blood at such a time, is farther confirm'd by that great quantity of Urine those Persons are apt to make: which has made some fear a Diabetes that have not been well versed in such Cases: for the Urine here will look very pale and limpid. And this may be further proved that when the Cuticular Glands are hinder'd from doing their transpiring office, particularly by any cold ambient Fluid which happens to them that go into water, that then they are obliged to throw off greater quantities of Urine, which has been observed by me to be very pale and insipid, after a second or third Evacuation. But I must not be too tedious. Experiment VII. Of Cold produced by a very great Ebullition wherein the cold and hot Fits of an Ague are resembled by a mixture of Liquors. If we use in this Experiment any Acid, whether of Vinegar, Verjuice, Wood Sorrel, Oranges, Limmons, or perhaps yet milder ones, by casting into these Juices a volatile Salt of Human Blood, I always observed a notable Ebullition would ensue, which I never could find would heat as such boiling Liquors are apt to do (and one would expect expect they should) but on the contrary affected a good Weather Glass so as to make the Liquor descend, which was a manifest token of Cold. There I found that the higher the Acid was, the greater the Ebullition and the Cold would be, which is very remarkable. For this very Reason I made use of very strong Vinegar, dephegm'd by freezing (which way is taught by the Honourable Mr. Boyle, to whose great favors and manuduction I must ascribe whatever service I shall be able to do Experimental Philosophy) by this mixture we came much nearer the freezing Point. But since it proves troublesome to prepare this Vinegar, and because it can be done only at certain times, I have most commonly made the Experiment with Spirit of Venus, or Verdigrase, which is the highest Vinegar in the world: with this the Cold will be most sensible to the Touch, and most conspicuous on the Weather Glass. For by this mixture I have in summer made a Weather Glass to descend below the Temperament of cold Fountain water, six Inches at least, which brought it so near the freezing mark that it scarce wanted half an Inch. But at the same time the Liquor swells and takes up more room than before, and will not be contained in shallow Vessels. In this Experiment we have some things very rare, that a great and violent motion of two dissenting Liquors, should be so far from producing Heat as to produce a notable degree of Cold, and that too with a considerable expansion of their parts. Here we might instance in an apposite and as unexpected an Experiment, where an effect contrary to our common observation happens, and that is thus, if you mix with Oyl of Vitriol a quantity of water, a great heat will follow without an Expansion of these Liquors, whereas heatdo's constantly produce it in Wine, Water, and most fluid and solid bodies; for here it rather shrinks and condenses, as you may see by making the Experiment in a Glass with a long Neck, and setting your mark as soon as you make your mixture. Both these Instances may a little puzzle the Cartesian tesian Hypothesis to account for, tho I am far from thinking they are able to destroy them. But to proceed with our Experiment, after I had sufficiently satisfied the worthy Spectators, that the produced degree of Cold was very considerable, I then poured in some few drops of another Liquor, that soon alter'd the temper of our Cold mixture and in two or three Minutes brought it to a warmth beyond that of the Ambient Air, tho it was a very warm Sun-shining day, in July. To apply the Experiment. In the Cold Fit of an Ague we have often a strong and quick Pulse, which argues an Ebullition (tho I dare not call it an Effervescence) and quick motion of the Blood, and the pains of the head and other parts may be due, to too great distress or extension of the Vessels, which depends on the expansion of the boiling humours. In this artificial tho cold mixture we observe, a mighty commotion and high Ebullition and expansion of the Liquor. In the Blood and other Juices of the body we constantly discover great quantities of volatile Salts, and sometimes either from an infected Air, or bad dyet, and from several other causes, sour Juices may be derived to the blood, which may act upon these volatile Salts, the blood so much abounds with, as to give a notable sense of cold. It is no new thing for us to meet with Patients, that have thrown upon their Stomachs and Bowels (which are the great Emunctories of the Blood) very sour Liquors, such as when they happen to fall upon the Teeth will corrode those hard parts. Thus in our Experiment tis plain that a foreign acid meeting with a volatile Salt drawn from the blood, does produce a cold effect; and since we know no Liquors but a mixture of this kind that gives us such a cold Phenomenon, it seems not unreasonable to believe that the cold Fit of an Ague may be due to such a mixture. As to the Incalcescence made in our mixture, I should have told you that it was done by the bare addition of some drops of Oil of Sulphur per Campanam, being a Liquor that owes its Origine to the fire, I suppose it to have borrowed that Calorifrick qualitie thence, which made it represent the hot Fit: for this I observed that notwithstanding the action of the Cold mixture, it grew more thick and slimy than twas at first, and that the addition of the mention'd Oil, or Spirit of Brimstone made it more clear and fluid. Thus the agile Spirits of the humane body, which tho they cannot be thought to be actual fire, yet are supposed to be somewhat Analogous to it, being in more abundance poured into the turbid Mass of Blood, do by their warmth and action first attenuate those gross Coagulums, and then manifestly subdue, and reduce many of those indisposed Particles to a good Texture, and expel those that are disagreeable by sweat and Urine or both ways; which is a good Prognostick of a cure of that Paroxism. I shall only add this Objection made, viz. That there are no such Acids of so high a degree of Acidity found in the human body as we make our Experiments with. I may answer that there is no need also of so great a degree of Cold to put our blood into an Ague, a small declination from its usual Temperature, being sufficient to make us very sensible. Postscript Postscript. I shall here only hint by way of Postscript an ingenious Proposition of a very worthy Person of the Society, to try whether the Cortex Peruvianus would not prevent this Artificial Ague our Liquors produced: which we brought to Tryal, tho the success did not answer. For we made a strong Infusion of our Bark in common Vinegar and then injected a quantity of the mention'd volatile Salt, a considerable Commotion of the Liquor infused with a degree of Cold, but was not altogether so fierce as formerly, moreover it abated much of rising to the height of the former Experiment, when Opium was mixt with the mention'd Cortex: tho in this case the Acidity was far from being quite mortified. As to the Cortex I do not intend in this Experiment to explain its Nature, which was only made to satisfy that sagacious Gentleman's Curiosity: for I never thought that febrifuge did act the part of an Alkali in performing the Cure. But if I can make it appear that there are other Medicines that do pertain or belong to the families of Alkaly's, which are effectual in the cure of Agues, this may serve to prove, that they do it by destroying some morbid Acidities in the humours or Viscera, and so prevent the usual Commotions such disagreeable Liquids are apt to make upon their Conventions. This is manifest that Coral and Crabs' eyes and other Testaceons bodies number'd amongst the first Alkaly's and not only these but those real first Salts, as Sal Absinthii, Cardui benedicti &c. as well as the volatile Salts in general, do highly correct and change Acid humours where they can meet them, and not only so but do hinder Liquors that are apt to sour and corrupt from degenerating: (thus Milk and Blood itself may be preserved much longer; the first from growing sour, the last from fermenting and putrifying by a quantity of volatile salt or Spirit mixt with them:) which is in like manner granted to be true, that many Agues have been cured by Medicines of this Nature. Sal absinthy as well as volatile Salts are used as the principal Ingredients in common Febrifuges. For a farther prosecution of this Experiment, we dissolved as much Chalk as strong Vinegar was able to do, and then having strained it through a Filter, we poured it upon a quantity of the highly rectified Spirit of Blood, but found neither Ebullition, or any sensation of cold or heat to follow.