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name) motion of liberty; which is, when any body, being forced to 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 these sounds are produced by the subtile percussion 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.2 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

These experiments are taken from Porta's Natural Magic, xviii. 1. and 3.

2 The wine and water are not separated from one another; all that takes place is that the water contained in the upper glass descends through the wine and water without perceptibly mixing with it, and settles at the bottom. The case is one of unstable equilibrium gradually becoming stable.

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 his 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.

Of course; as in the contrary case the equilibrium is stable.

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 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


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 stood twentyfour 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 the grosser part.2

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

Lay in the original, in both places.-J. S. 2 Is in the grosser part. Ed. 1635.-J. S.

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 spirits in some cases, so we may desire also to discharge them (as hurtful) in some other. So wine burnt, by reason of the evaporating of the finer spirit, inflameth less, and is best in agues: opium leeseth some of his poisonous quality, if it be vapoured out, mingled with spirit of wine, or the like: sean loseth somewhat of his windiness by decocting; and (generally) subtile or windy spirits are taken off by incension or evaporation. And even in infusions in things that are of too high a spirit, you were better pour off the first infusion, after a small time, and use the latter.

Experiment solitary touching the appetite of continuation in


24. Bubbles are in the form of an 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.1 In this common experiment,

"Declinat, inquit, atomus. Primum cur? aliam quandam vim motus habebunt a Democrito impulsionis, quam plagam ille appellat.”—Cicero, De Fato, c. 20. It is difficult to determine whether this notion of "plaga" involved the conception of

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 round figure. And for the stop and arrest of the air a little while, it sheweth that the air of itself hath little or no appetite of ascending.

Experiment solitary touching the making of artificial 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, of a good length, three or four foot deep within the same ground; with one end upon the high ground, the other upon the low. Cover the trough with brakes a good thickness, and cast sand upon the top of the brakes. You shall see (saith he) that after some showers are past, the lower end of the trough will run like a spring of water: which is no marvel, if it hold while the rain-water lasteth; but he said it would continue long time after the rain is past: as if the water did multiply itself upon the air, by the help of the coldness and condensation of the earth, and the consort of the first water.

Experiment solitary touching the venomous quality of man's flesh.

26. The French (which put off the name of the French

a mutual action between the atoms. See Mullach. Democrit. Abder. Oper. Frag. p. 384.

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