very dashing of the water, that cometh from the fea, is more proper to strike off the falt part, than where the water flideth of its own motion. 3. Ir feemeth Percolation, or Tranfmiffion, (which is commonly called ftraining) is a good kind of feparation, not only of thick from thin, and grofs from fine, but of more fubtile natures; and varieth according to the body through which the tranfmiffion is made as if through a woollen bag, the liquor leaveth the fatnefs; if through fand, the faltnefs, &c. They fpeak of fevering wine from water, paffing it through ivy wood, or through other the like porous body; but non conftat. 4. THZ gum of trees (which we fee to be commonly fhining and clear) is but a fine paffage or ftraining of the juice of the tree through the wood and bark. And in like manner, cornifh diamonds, and rock rubies (which are yet more refplendent than gums) are the fine exudations of stone. 5. ARISTOTLE giveth the cause, vainly, why the feathers of birds are of more lively colours, than the hairs of beafts; for no beast hath any fine azure, or carnation, or green hair. He faith, it is, because birds are more in the beams of the fun than beasts; but that is manifeftly untrue; for cattle are more in the fun than birds, that live commonly in the woods, or in fome covert. The true caufe is, that the excrementitious moisture of living creatures, which maketh as well the feathers in birds, as the hair in beafts, paffeth in birds through a finer and more delicate ftrainer than it doth in beafts: for feathers pafs through quills; and hair through skin. 6. THE clarifying of liquors by adhesion, is an inward Percolation; and is effected, when fome cleaving body is mixed and agitated with the liquors ; whereby the groffer part of the liquor fticks to that cleaving body; and fo the finer parts are freed from the groffer. So the apothecaries clarify their fyrups by whites of eggs, beaten with the juices which they would clarify; which whites of eggs gather all the dregs and groffer parts of the juice to them; and after the fyrup being fet on the fire, the whites of eggs themfelves harden, and are taken forth. So ippocrafs is clarified by mixing with milk, and stirring it about, and then paffing it through a woollen bag, which they call Hippocrates's Sleeve, and the cleaving nature of the milk draweth the powder of the fpices, and groffer parts of the liquor to it; and in the paffage they stick upon the woollen bag. 7. THE clarifying of water, is an experiment tending to health; befides the pleasure of the eye, when water is cryftalline. It is effected by cafting in and placing pebbles at the head of the current, that the water may ftrain through them. 8. IT may be, Percolation doth not only caufe clearness and fplendour, but sweetness of favour; for that alfo followeth as well as clearness, when the finer parts are fevered from the groffer. So it is found, that the fweats, of men, that have much heat, and exercise much, and have clean bodies, and fine fkins, do smell fweet; as was faid of Alexander; and we fee, commonly that gums have sweet odours. 9. Experiments in confort, touching Motion of bodies upon their preffure. TAKE a glass, and put water into it, and wet your finger, and draw it round about the lip of the glafs, preffing it fomewhat hard; and after you have drawn it fome few times about, it will make the water frifk and fprinkle up, in a fine dew. This inftance doth excellently demonftrate the force of compreffion in a folid body for whenfoever a folid body (as wood, ftone, metal, &c.) is preffed, there is an inward tumult in the parts thereof, feeking to to deliver themselves from the compreffion and this is the caufe of all violent motion. Wherein it is strange, in the highest degree, that this motion hath never been obferved, nor inquired; it being of all motions the most common, and the chief root of all mechanical operations. This motion worketh in round at firft, by way of proof and fearch, which way to deliver it felf; and then worketh in progrefs, where it findeth the deliverance cafieft. In liquors this motion is vifible; for all liquors ftrucken make round circles, and withal dafh; but in folids (which break not) it is fo fubtile, as it is invifible; but nevertheless bewrayeth it felf by many effects; as in this inftance whereof we fpeak. For the preffure of the finger, furthered by the wetting, (because it sticketh fo much the better unto the lip of the glafs) after fome continuance, putteth all the fmall parts of the glafs into work; that they strike the water fharply; from which percuffion that fprinkling cometh. 10. IF you strike or pierce a folid body, that is brittle, as glass, or fugar, it breaketh not only where the immediate force is; but breaketh all about into shivers and fitters; the motion, upon the preffure, fearching all ways, and breaking where it findeth the body weakest. 11. THE powder in fhot, being dilated into fuch a flame, as endureth not compreffion, moveth likewife in round, (the flame being in the nature of a liquid body) fometimes recoiling; fometimes breaking the piece; but generally discharging the bullet, because there it findeth easiest deliverance. 12. THIS motion upon preffure, and the reciprocal thereof, which is motion upon tenfure, we ufe to call (by one common name) motion of liberty; which is, when any body, being forced to a preternatural extent or dimenfion, delivereth and reftoreth it felf to the natural: as when a blown bladder (preffed) rifeth again; or when leather or cloth tentured, fpring back. Thefe two motions (of which there be infinite inftances) we fhall handle in due place. 13. THIS motion upon preffure is excellently alfo demonftrated in founds; as when one chimeth upon a bell, it foundeth; but as foon as he layeth his hand upon it, the found ceafeth: and fo, the found of a virginal firing, as foon as the quill of the jack falleth from it, ftoppeth. For thefe founds are produced by the fubtile percuffion of the minute part of the bell, or ftring, upon the air, all one, as the water is caufed to leap by the fubtile percuffion of the minute parts of the glass, upon the water, whereof we fpake a little before in the ninth experiment. For you must not take it to be the local fhaking of the bell, or ftring, that doth it: as we fhall fully declare, when we come hereafter to handle founds. Experiments in confort, touching Separations of bodies by weight. 14. TAKE a glass with a belly and a long neb; fill the belly (in part) with water: take also another glass, whereinto put claret wine and water mingled; reverse the first glafs, with the belly upwards, ftopping the neb with your finger; then dip the mouth of it within the fecond glafs, and remove your finger: continue it in that pofture for a time; and it will unmingle the wine from the water: the wine afcending and fettling in the top of the upper glafs; and the water defcending and fettling in the bottom of the lower glafs. The paffage is apparent to the eye; for you fhall fee the wine, as it were, in a small vein, rifing through the water. For handfomness fake (because the working requireth fome fmall time) it were good you hang the upper glass upon a nail. But as foon as there is gathered fo much pure and VOL. III. unmixed A 2 unmixed water in the bottom of the lower glass, as that the mouth of the upper glass dippeth into it, the motion ceaseth. 15. LET the upper glafs be wine, and the lower water; there followeth no motion at all. Let the upper glass be water pure, the lower water coloured, or, contrariwife, there followeth no motion at all. But it hath been tried, that though the mixture of wine and water, in the lower glass, be three parts water and but one wine, yet it doth not dead the motion. This separation of water and wine appeareth to be made by weight; for it must be of bodies of unequal weight, or else it worketh not; and the heavier body must ever be in the upper glass. But then note, withal, that the water being made penfile, and there being a great weight of water in the belly of the glass, fuftained by a small pillar of water in the neck of the glass, it is that which fetteth the motion on work: For water and wine in one glass, with long standing, will hardly fever. 16. THIS experiment would be extended from mixtures of feveral liquors, to fimple bodies, which confift of several fimilar parts: try it therefore with brine, or falt-water, and fresh-water: placing the falt-water (which is the heavier) in the upper glafs; and fee whether the fresh will come above. Try it also with water thick fugared, and pure water; and fee whether the water, which cometh above, will lofe its sweetness: for which purpose it were good there were a little cock made in the belly of the upper glass. Experiments in confort, touching judicious and accurate infufions, both in liquors and air. 17. IN bodies containing fine fpirits, which do eafily diffipate, when you make infufions, the rule is; a short stay of the body in the liquor, receiveth the fpirit; and a longer ftay, confoundeth it; because it draweth forth the earthy part withal, which embaseth the finer. And therefore it is an error in phyficians, to reft fimply upon the length of stay, for increafing the virtue. But if you will have the infufion ftrong, in thofe kinds of bodies which have fine fpirits, your way is not to give longer time, but to repeat the infufion of the body oftner. Take violets, and infufe a good pugil of them in a quart of vinegar; let them ftay three quarters of an hour, and take them forth, and refresh the infufion with like quantity of new violets, seven times; and it will make a vinegar fo fresh of the flower, as if a twelvemonth after, it be brought you in a faucer, you fhall fmell it before it come at you. Note, that it fmelleth more perfectly of the flower, a good while after than at first. 18. THIS rule, which we have given, is of fingular ufe for the preparations of medicines, and other infufions. As for example: the leaf of burrage hath an excellent fpirit, to reprefs the fuliginous vapour of dufky melancholy, and fo to cure madness: but nevertheless, if the leaf be infufed long, it yieldeth forth but a raw fubftance, of no virtue: therefore I fuppofe, that if in the must of wine, or wort of beer, while it worketh, before it be tunned, the burrage stay a small time, and be often changed with fresh; it will make ., a fovereign_ drink for melancholy paffions. And the like I conceive of orange flowers. 16 RHUBARB hath manifeftly in it parts of contrary operations: parts that purge; and parts that bind the body: and the first lay loofer, and the latter lay deeper: fo that if you infufe rhubarb for an hour, and crush it well, it will purge better, and bind the body lefs after the purging, than if it stood twenty four hours; this tried: but I conceive likewife, that by repeating the the infufion of rhubarb, several times, (as was faid of violets,) letting each stay in but a small time; you may make it as ftrong a purging medicine, as fcammony. And it is not a fmall thing won in phyfick, if you can make rhubarb, and other medicines that are benedict, as ftrong purgers, as thofe that are not without fome malignity. 20. PURGING medicines, for the most part, have their purgative virtue in a fine fpirit; as appeareth by that they endure not boiling without much lofs of virtue. And therefore it is of good ufe in phyfick, if you can retain the purging virtue, and take away the unpleasant tafte of the purger; which it is like you may do, by this course of infufing oft, with little ftay. For it is probable, that the horrible and odious tafte, is in the groffer part. 21. GENERALLY, the working by infufions, is grofs and blind, except you first try the iffuing of the feveral parts of the body, which of them iffue more fpeedily, and which more flowly; and fo by apportioning the time, can take and leave that quality, which you defire. This to know, there are two ways; the one to try what long ftay, and what short stay worketh, as hath been faid: the other to try in order, the fucceeding infufions, of one and the fame body, fucceffively in feveral liquors. As for example; take orange pills, or rosemary, or cinnamon, or what you will; and let them infufe half an hour in water: then take them out, and infuse them again in another water; and fo the third time: and then tafte and confider the first water, the second, and the third and you will find them differing, not only in strength and weakness, but otherwise in taste or odour; for it may be the first water will have more of the fcent, as more fragrant; and the fecond more of the taste, as more bitter or biting, &c. 22. INFUSIONs in air, (for fo we may well call odours) have the fame diverfities with infufions in water; in that the feveral odours (which are in one flower, or other body) iffue at several times; fome earlier, fome later: fo we find that violets, woodbines, ftrawberries, yield a pleafing fcent, that cometh forth firft; but soon after an ill fcent quite differing from the forWhich is caused, not so much by mellowing, as by the late iffuing of the groffer fpirit. mer. 23. As we may defire to extract the finest spirits in fome cafes; fo we may defire also to discharge them (as hurtful) in fome other. So wine burnt, by reafon of the evaporating of the finer fpirit, enflameth lefs, and is beft in agues opium lofeth fome of his poifonous quality, if it be vapoured out, mingled with fpirit of wine, or the like: fena lofeth fomewhat of its windinefs by decocting; and (generally) fubtile or windy fpirits are taken off by incenfion, or evaporation. And even in infufions in things that are of too high a fpirit, you were better pour off the first infufion, after a small time, and ufe the later. Experiment folitary touching the appetite of continuation in liquids. : 24. BUBBLES are in the form of an hemifphere; air within, and a little skin of water without and it feemeth somewhat strange, that the air should rife so swiftly, while it is in the water; and when it cometh to the top, fhould be stayed by fo weak a cover as that of the bubble is. But as for the fwift afcent of the air, while it is under the water, that is a motion of percuffion from the water; which it felf defcending, driveth up the air; and no motion of levity in the air. And this Democritus called Motus Plagae. In this common experiment, the cause of the enclosure of the bubble is, for that the appetite to refift separation, or discontinuance, (which in folid bo dies dies is ftrong) is alfo in liquors, though fainter and weaker; as we fee in this of the bubble: we fee it alfo in little glaffes of fpittle that children make of rushes; and in caftles of bubbles, which they make by blowing into water, having obtained a little degree of tenacity by mixture of foap: we fee it alfo in the ftillicides of water, which if there be water enough to follow, will draw themselves into a small thread, because they will not difcontinue; but if there be no remedy, then they caft themselves into round drops; which is the figure that faveth the body most from difcontinuance: the fame reason is of the roundness of the bubble, as well for the skin of water, as for the air within for the air likewife avoideth discontinuance; and therefore cafteth it felf into a round figure. And for the ftop and arreft of the air a little while, it sheweth that the air of it felf hath little or no appetite of afcending. Experiment folitary touching the making of artificial Springs. 25. THE rejection, which I continually ufe, of experiments, (though it appeareth not) is infinite; but yet if an experiment be probable in the work, and of great use, I receive it, but deliver it as doubtful. It was reported by a fober man, that an artificial fpring may be made thus: find out a hanging ground, where there is a good quick fall of rain-water. Lay a half-trough of ftone, of a good length, three or four foot deep within the fame ground; with one end upon the high ground, the other upon the low. Cover the trough with brakes a good thicknefs, and caft fand upon the top of the brakes: you fhall fee, (faith he) that after fome showers are paft, the lower end of the trough will run like a spring of water: which is no marvel, if it hold while the rain-water lafteth; but he faid it would continue long time after the rain is paft: as if the water did multiply it felf upon the air, by the help of the coldnefs and condenfation of the earth, and the confort of the first water. Experiment folitary touching the venomous quality of man's flesh. 26. THE French, (which put off the name of the French disease, unto the name of the disease of Naples,) do report, that at the fiege of Naples, there were certain wicked merchants that barrelled up man's flesh, (of fome that had been lately flain in Barbary) and fold it for tunney; and that and that upon that foul and high nourishment, was the original of that difcafe. Which may well be; for that it is certain, that the canibals in the West-Indies, eat man's flesh; and the Weft-Indies were full of the pox when they were first discovered: and at this day the mortaleft poifons, practifed by the Weft-Indians, have fome mixture of the blood, or fat, or flesh of man: and divers witches, and forcereffes, as well amongst the heathen, as amongst the chriftians, have fed upon man's flesh, to aid (as it seemeth) their imagination, with high and foul vapours. Experiment folitary touching the verfion and tranfmutation of air into water. 27. IT feemeth that there be these ways (in likelihood) of verfion of vapours or air, into water and moisture. The first is cold; which doth manifeftly condense; as we fee in the contracting of the air in the weather-glais;whereby it is a degree nearer to water. We fee it alfo in the generation of fprings, which the antients thought (very probably) to be made by the verfion of air into water, holpen by the reft, which the air hath in thofe parts; whereby it cannot diffipate. And by the coldness of rocks; for there fprings are chiefly generated. We fee it alfo in the effects of the cold of the middle 3 region |