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10. If you strike or pierce a solid body that is brittle, as glass, or sugar, it breaketh not only where the immediate force is; but breaketh all about into shivers and fitters; the motion, upon the pressure, searching all ways, and breaking where it findeth the body weakest.

are freed from the grosser. So the apothecaries clarify their syrups by whites of eggs, beaten with the juices which they would clarify; which whites of eggs gather all the dregs and grosser parts of the juice to them; and after the syrup being set on the fire, the whites of eggs themselves harden, and are taken forth. So hippocras 11. The powder in shot, being dilated into is clarified by mixing with milk, and stirring it such a flame as endureth not compression, moveth about, and then passing it through a woollen bag, likewise in round, the flame being, in the nature which they call Hippocrates's Sleeve, and the of a liquid body, sometimes recoiling, sometimes cleaving nature of the milk draweth the powder breaking the piece, but generally discharging the of the spices, and grosser parts of the liquor to it; | bullet, because there it findeth easiest deliverand in the passage they stick upon the woollen ance. bag.

12. This motion upon pressure, and the reci7. The clarifying of water is an experiment tend-procal thereof, which is motion upon tensure, we ing to health; besides the pleasure of the eye, use to call, by one common name, motion of liwhen water is crystalline. It is effected by cast-berty; which is, when any body, being forced to ing in and placing pebbles at the head of a current, that the water may strain through them.

8. It may be, percolation doth not only cause clearness and splendour, but sweetness of savour; for that also followeth as well as clearness, when the finer parts are severed from the grosser. So it is found, that the sweats of men, that have much heat, and exercise much, and have clean bodies, and fine skins, do smell sweet; as was said of Alexander; and we see commonly that gums have sweet odours.

a preternatural extent or dimension, delivereth and restoreth itself to the natural: as when a blown bladder pressed, riseth again; or when leather or cloth tentured, spring back. These two motions, of which there be infinite instances, we shall handle in due place.

13. This motion upon pressure is excellently also demonstrated in sounds; as when one chimeth upon a bell, it soundeth; but as soon as he layeth his hand upon it, the sound ceaseth: and so the sound of a virginal string, as soon as the quill of the jack falleth from it, stoppeth. For

Experiments in consort, touching motion of bodies these sounds are produced by the subtile percus

upon their pressure.

9. Take a glass, and put water into it, and wet your finger, and draw it round about the lip of the glass, pressing it somewhat hard; and after you have drawn it some few times about, it will make the water frisk and sprinkle up in fine dew. This instance doth excellently demonstrate the force of compression in a solid body: for whensoever a solid body, as wood, stone, metal, &c. is pressed, there is an inward tumult in the parts thereof seeking to deliver themselves from the compression: and this is the cause of all violent motion. Wherein it is strange in the highest degree, that this motion hath never been observed, nor inquired; it being of all motions the most common, and the chief root of all mechanical operations. This motion worketh in round at first, by way of proof and search which way to deliver itself: and then worketh in progress where it findeth the deliverance easiest. In liquors this motion is visible; for all liquors strucken make round circles, and withal dash; but in solids, which break not, it is so subtile as it is invisible; but nevertheless bewrayeth itself by many effects; as in this instance whereof we speak. For the pressure of the finger, furthered by the wetting, because it sticketh so much the better unto the lip of the glass, after some continuance, putteth all the small parts of the glass into work, that they strike the water sharply; from which percussion that sprinkling

cometh.

sion of the minute parts of the bell, or string, upon the air; all one, as the water is caused to leap by the subtile percussion of the minute parts of the glass, upon the water, whereof we spake a little before in the ninth experiment. For you must not take it to be the local shaking of the bell, or string, that doth it: as we shall fully declare, when we come hereafter to handle sounds.

Experiments in consort, 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 glass, with the belly upwards, stopping the neb with your finger; then dip the mouth of it within the second glass, and remove your finger: continue it in that posture for a time; and it will unmingle the wine from the water: the wine ascending and settling in the top of the upper glass; and the water descending and settling in the bottom of the lower glass. The passage is apparent to the eye; for you shall see the wine, as it were, in a small vein, rising through the water. For handsomeness' sake, because the working requireth some small time, it were good you hang the upper glass upon a nail. But as soon as there is gathered so much pure and 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 glass be wine, and the lower water; there followeth no motion at all. Let the upper glass be water pure, the lower water coloured, or contrariwise, 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 pensile, and there being a great weight of water in the belly of the glass, sustained by a small pillar of water in the neck of the glass, it is that which setteth the motion on work: for water and wine in one glass, with long standing, will hardly sever.

16. This experiment would be extended from mixtures of several liquors, to simple bodies which consist of several similar parts: try it therefore with brine or salt-water, and fresh water: placing the salt-water, which is the heavier, in the upper glass; and see whether the fresh will come above. Try it also with water thick sugared, and pure water; and see whether the water, which cometh above, will lose its sweetness: for which purpose it were good there were a little cock made in the belly of the upper glass.

Experiments in consort, touching judicious and accurate infusions, both in liquors and air. 17. In bodies containing fine spirits, which do easily dissipate, when you make infusions, the rule is, a short stay of the body in the liquor receiveth the spirit; and a longer stay confoundeth it; because it draweth forth the earthy part withal, which embaseth the finer. And therefore it is an error in physicians, to rest simply upon the length of stay for increasing the virtue. But if you will have the infusion strong, in those kinds of bodies which have fine spirits, your way is not to give longer time, but to repeat the infusion of the body oftener. Take violets, and infuse a good pugil of them in a quart of vinegar; let them stay three quarters of an hour, and take them forth, and refresh the infusion with like quantity of new violets seven times; and it will make a vinegar so fresh of the flower, as if, a twelvemonth after, it be brought you in a saucer, you shall smell it before it come at you. Note, that it smelleth more perfectly of the flower a good while after than at first.

18. This rule, which we have given, is of singular use for the preparations of medicines, and other infusions. As for example: the leaf of burrage hath an excellent spirit to repress the fuliginous vapour of dusky melancholy, and so to cure madness: but nevertheless if the leaf be infused long it yieldeth forth but a raw substance, of no virtue: therefore I suppose, that if in the VOL. II.-2

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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 sovereign drink for melancholy passions. And the like I conceive of orange flowers.

19. Rhubarb hath manifestly in it parts of contrary operations: parts that purge; and parts that bind the body; and the first lie looser, and the latter lie deeper: so that if you infuse rhubarb for an hour, and crush it well, it will purge better, and bind the body less after the purging than if it had stood twenty-four hours; this is tried; but I conceive likewise, that by repeating the infusion of rhubarb several times, as was said of violets, letting each stay in but a small time, you may make it as strong a purging medicine as scammony. And it is not a small thing won in physic, if you can make rhubarb, and other medicines that are benedict, as strong purgers as those that are not without some malignity.

20. Purging medicines, for the most part, have their purgative virtue in a fine spirit; as appeareth by that they endure not boiling without much loss of virtue. And therefore it is of good use in physic, if you can retain the purging virtue, and take away the unpleasant taste of the purger; which it is like you may do, by this course of infusing oft, with little stay, for it is probable that the horrible and odious taste is in the grosser part.

21. Generally, the working by infusions is gross and blind, except you first try the issuing of the several parts of the body, which of them issue more speedily, and which more slowly; and so by apportioning the time, can take and leave that quality which you desire. This to know there be two ways; the one to try what long stay, and what short stay worketh as hath been said; the other to try in order the succeeding infusions of one and the same body, successively, in several liquors. As, for example; take orange pills, or rosemary, or cinnamon, or what you will; and let them infuse half an hour in water; then take them out, and infuse them again in other water; and so the third time: and then taste and consider 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 scent, as more fragrant; and the second more of the taste, as more bitter or biting, &c.

22. Infusions in air, for so we may well call odours, have the same diversities with infusions in water; in that the several odours, which are in one flower, or other body, issue at several times; some earlier, some later: so we find that violets, woodbines, strawberries, yield a pleasing scent, that cometh forth first; but soon after an ill scent quite differing from the former. Which is caused, not so much by mellowing, as by the late issuing of the grosser spirit.

23. As we may desire to extract the finest of a good length, three or four foot deep within spirits in some cases; so we may desire also to the same ground; with one end upon the high discharge them, as hurtful, in some other. So ground, the other upon the low. Cover the trough wine burnt, by reason of the evaporating of the with brakes a good thickness, and cast sand upon finer spirit, inflameth less, and is best in agues: the top of the brakes: you shall see, saith he, opium loseth some of its poisonous quality, if it that after some showers are past, the lower end be vapoured out, mingled with spirits of wine, or of the trough will run like a spring of water: the like: sena loseth somewhat of its windiness which is no marvel, if it hold while the rainby decocting; and generally, subtile or windy water lasteth; but he said it would continue long spirits are taken off by incension, or evaporation. time after the rain is past: as if the water did And even in infusions in things that are of too multiply itself upon the air, by the help of the high a spirit, you were better pour off the first coldness and condensation of the earth, and the infusion, after a small time, and use the latter. consort of the first water.

Experiment solitary touching the appetite of con- Experiment solitary touching the venomous quality

tinuation in liquids.

24. Bubbles are in the form of a hemisphere; air within, and a little skin of water without: and it seemeth somewhat strange, that the air should rise so swiftly while it is in the water; and when it cometh to the top, should be stayed by so weak a cover as that of the bubble is. But as for the swift ascent of the air, while it is under the water, that is a motion of percussion from the water; which itself descending driveth up the air; and no motion of levity in the air. And this Democritus called "motus plaga." In this common experiment, the cause of the inclosure of the bubble is, for that the appetite to resist separation, or discontinuance, which in solid bodies is strong, is also in liquors, though fainter and weaker; as we see in this of the bubble: we see it also in little glasses of spittle that children make of rushes; and in castles of bubbles, which they make by blowing into water, having obtained a little degree of tenacity by mixture of soap: we see it also in the stillicides of water, which if there be water enough to follow, will draw themselves into a small thread, because they will not discontinue; but if there be no remedy, then they cast themselves into round drops; which is the figure that saveth the body most from discontinuance: the same reason is of the roundness of the bubble, as well for the skin of water, as for the air within: for the air likewise avoideth discontinuance; and therefore casteth itself into a rough figure. And for the stop and arrest of the air a little while, it showeth that the air of itself hath little or no appetite of ascending.

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 siege of Naples,
there were certain wicked merchants that barrelled
up man's flesh, of some that had been lately slain
in Barbary, and sold it for tunney; and that upon
that foul and high nourishment was the original
of that disease. Which may well be, for that it
is certain that the cannibals in the West Indies
eat man's flesh: and the West Indies were full
of the pox when they were first discovered: and
at this day the mortalest poisons, practised by
the West Indians, have some mixture of the
blood, or fat, or flesh of man: and divers witches
and sorceresses, as well amongst the heathen, as
amongst the Christians, have fed upon man's
flesh, to aid, as it seemeth, their imagination,
with high and foul vapours.

Experiment solitary touching the version and trans-
mutation of air into water.

27. It seemeth that there be these ways, in likelihood, of version of vapours of air into water and moisture. The first is cold; which doth manifestly condense; as we see in the contracting of the air in the weather-glass; whereby it is a degree nearer to water. We see it also in the generation of springs, which the ancients thought, very probably, to be made by the version of air into water, holpen by the rest, which the air hath in those parts; whereby it cannot dissipate. And by the coldness of rocks; for there springs are chiefly generated. We see it also in the effects of the cold of the middle region, as they call it, of the air; which produceth dews Experiment solitary touching the making of artifi- and rains. And the experiment of turning water

cial springs.

25. The rejection, which I continually use, 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 sober man, that an artificial spring may be made thus: Find out a hanging ground, where there is a good quick fall of rain-water. Lay a half trough of stone,

into ice, by snow, nitre, and salt, whereof we
shall speak hereafter, would be transferred to the
turning of air into water. The second way is by
compression; as in stillatories, where the vapour
is turned back upon itself, by the encounter of
the sides of the stillatory; and in the dew upon
the covers of boiling pots; and in the dew
towards rain, upon marble and wainscot. But
this is like to do no great effect; except it be

1

Experiment solitary touching the condensing of air in such sort as it may put on weight, and yield nourishment.

29. Onions, as they hang, will many of them shoot forth; and so will penny-royal; and so will an herb called orpin; with which they use in the country to trim their houses, binding it to a lath or stick, and setting it against a wall. We see it likewise more especially in the greater semper-vive, which will put out branches, two or three years: but it is true, that commonly they wrap the root in a cloth besmeared with oil, and

upon vapours, and gross air, that are already very near in degree to water. The third is that, which may be searched into, but doth not yet appear; which is, by mingling of moist vapours with air; and trying if they will not bring a return of more water than the water was at first: for if so, that increase is a version of the air: therefore put water in the bottom of a stillatory, with the neb stopped; weigh the water first; hang in the middle of the stillatory a large spunge; and see what quantity of water you can crush out of it; and what it is more or less compared with the water spent; for you must under-renew it once in half a year. The like is reported, stand, that if any version can be wrought, it will be easiliest done in small pores: and that is the reason why we prescribe a spunge. The fourth way is probable also, though not appearing; which is, by receiving the air into the small pores of bodies: for, as hath been said, every thing in small quantity is more easy for version; and tangible bodies have no pleasure in the consort of air, but endeavour to subact it into a more dense body; but in entire bodies it is checked; because if the air should condense, there is nothing to succeed: therefore it must be in loose bodies, as sand, and powder; which we see, if they lie close, of themselves gather moisture.

by some of the ancients, of the stalks of lilies. The cause is; for that these plants have a strong, dense, and succulent moisture, which is not apt to exhale; and so is able, from the old store, without drawing help from the earth, to suffice the sprouting of the plant: and this sprouting is chiefly in the late spring or early summer; which are the times of putting forth. We see also, that stumps of trees lying out of the ground, will put forth sprouts for a time. But it is a noble trial, and of very great consequence, to try whether these things, in the sprouting, do increase weight; which must be tried, by weighing them before they be hanged up; and afterwards again, when they are sprouted. For if they increase not in

Experiment solitary touching helps towards the weight, then it is no more but this; that what beauty and good features of persons.

28. It is reported by some of the ancients; that whelps, or other creatures, if they be put young into such a cage or box, as they cannot rise to their stature, but may increase in breadth or length, will grow accordingly as they can get room; which if it be true and feasible, and that the young creature so pressed and straitened, doth not thereupon die, it is a means to produce dwarf creatures, and in a very strange figure. This is certain, and noted long since, that the pressure or forming of parts of creatures, when they are very young, doth alter the shape not a little as the stroking of the heads of infants, between the hands, was noted of old, to make "Macrocephali;" which shape of the head, at that time, was esteemed. And the raising gently of the bridge of the nose, doth prevent the deformity of a saddle nose. Which observation well weighed, may teach a means to make the persons of men and women, in many kinds, more comely and better featured than otherwise they would be; by the forming and shaping of them in their infancy: as by stroking up the calves of the legs, to keep them from falling down too low; and by stroking up the forehead, to keep them from being low-foreheaded. And it is a common practice to swathe infants, that they may grow more straight, and better shaped: and we see young women, by wearing strait bodice, keep themselves from being gross and corpulent.

they send forth in the sprout, they lose in some other part: for if they gather weight, then it is " magnale naturæ;" for it it showeth that air may be made so to be condensed as to be converted into a dense body; whereas the race and period of all things, here above the earth, is to extenuate and turn things to be more pneumatical and rare; and not to be retrograde, from pneumatical to that which is dense. It showeth also, that air can nourish; which is another great matter of consequence. Note, that to try this, the experiment of the semper-vive must be made without oiling the cloth; for else, it may be, the plant receiveth nourishment from the oil.

Experiment solitary touching the commixture of

flame and air, and the great force thereof. 30. Flame and air do not mingle, except it be in an instant; or in the vital spirits of vegetables and living creatures. In gunpowder, the force of it hath been ascribed to rarefaction of the earthy substance into flame; and thus far it is true: and then, forsooth, it is become another element; the form whereof occupieth more place; and so of necessity, followeth a dilatation; and therefore, lest two bodies should be in one place, there must needs also follow an expulsion of the pellet; or blowing up of the mine. But these are crude and ignorant speculations. For flame, if there were nothing else, except it were in very great quantity, will be suffocate with any hard body, such as a pellet is; or the barrel of a gun;

so as the flame would not expel the hard body; but the hard body would kill the flame, and not suffer it to kindle or spread. But the cause of this so potent a motion, is the nitre, which we call otherwise saltpetre, which having in it a notable crude and windy spirit, first by the heat of the fire suddenly dilateth itself; and we know that simple air, being preternaturally attenuated by heat, will make itself room, and break and blow up that which resisteth it; and secondly, when the nitre hath dilated itself, it bloweth abroad the flame, as an inward bellows. And therefore we see that brimstone, pitch, camphire, wild-fire, and divers other inflammable matters, though they burn cruelly, and are hard to quench, yet they make no such fiery wind as gunpowder doth; and on the other side, we see that quicksilver, which is a most crude and watery body, heated, and pent in, hath the like force with gunpowder. As for living creatures, it is certain, their vital spirits are a substance compounded of an airy and flamy matter; and though air and flame being free, will not well mingle; yet bound in by a body that hath some fixing, they will. .For that you may best see in those two bodies, which are their aliments, water and oil; for they likewise will not well mingle of themselves; but in the bodies of plants, and living creatures, they will. It is no marvel therefore, that a small quantity of spirits, in the cells of the brain, and canals of the sinews, are able to move the whole body, which is of so great mass, both with so great force, as in wrestling, leaping; and with | so great swiftness, as in playing division upon the lute. Such is the force of these two natures, air and flame, when they incorporate.

It appeareth also, that the form of a pyramis in flame, which we usually see, is merely by accident, and that the air about, by quenching the sides of the flame, crusheth it, and extenuateth it into that form; for of itself it would be round; and therefore smoke is in the figure of a pyramis reversed; for the air quencheth the flame, and receiveth the smoke. Note also, that the flame of the candle, within the flame of the spirit of wine, is troubled; and doth not only open and move upwards, but moveth waving, and to and fro; as if flame of its own nature, if it were not quenched, would roll and turn, as well as move upwards. By all which it should seem, that the celestial bodies, most of them, are true fires or flames, as the Stoics held; more fine, perhaps, and rarified than our flame is. For they are all globular and determinate; they have rotation; and they have the colour and splendour of flame: so that flame above is durable, and consistent, and in its natural place; but with us it is a stranger, and momentary, and impure: like Vulcan that halted with his fall.

Experiment solitary touching the different force of flame in the midst and on the sides.

32. Take an arrow, and hold it in flame for the space of ten pulses, and when it cometh forth, you shall find those parts of the arrow which were on the outsides of the flame more burned, blacked, and turned almost into a coal, whereas that in the midst of the flame will be as if the fire had scarce touched it. This is an instance of great consequence for the discovery of the nature of flame; and showeth manifestly, that flame burneth more violently towards the sides than in the midst: and which is more, that heat

Experiment solitary touching the secret nature of or fire is not violent or furious, but where it is

flame.

31. Take a small wax candle, and put it in a socket of brass or iron; then set it upright in a porringer full of spirit of wine heated: then set both the candle and spirit of wine on fire, and you shall see the flame of the candle open itself, and become four or five times bigger than otherwise it would have been; and appear in figure globular, and not in pyramis. You shall see also, that the inward flame of the candle keepeth colour, and doth not wax any whit blue towards the colour of the outward flame of the spirit of wine. This is a noble instance; wherein two things are most remarkable: the one, that one flame within another quencheth not; but is a fixed body, and continueth as air or water do. And therefore flame would still ascend upwards in one greatness, if it were not quenched on the sides: and the greater the flame is at the bottom, the higher is the rise. The other, that flame doth not mingle with flame, as air doth with air, or water with water, but only remaineth contiguous; as it cometh to pass betwixt consisting bodies.

checked and pent. And therefore the Peripatetics, howsoever their opinion of an element of fire above the air is justly exploded, in that point they acquit themselves well: for being opposed, that if there were a sphere of fire, that encompassed the earth so near hand, it were impossible but all things should be burnt up; they answer, that the pure elemental fire, in its own place, and not irritated, is but of a moderate heat.

Experiment solitary touching the decrease of the natural motion of gravity, in great distance from the earth; or within some depth of the earth. 33. It is affirmed constantly by many, as a usual experiment, that a lump of ore in the bottom of a mine will be tumbled and stirred by two men's strength, which, if you bring it to the top of the earth, will ask six men's strength at the least to stir it. It is a noble instance, and is fit to be tried to the full; for it is very probable, that the motion of gravity worketh weakly, both far from the earth, and also within the earth: the former, because the appetite of union of dense

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