equality of the pressure of parts, it appeareth manifestly in this; that if you take a body of stone or iron, and another of wood, of the same magnitude and shape, and throw them with equal force, you cannot possibly throw the wood so far as the stone or iron. Experiment solitary touching water, that it may be the medium of sounds. 792. It is certain, as it hath been formerly in part touched, that water may be the medium of sounds. If you dash a stone against a stone in the bottom of the water, it maketh a sound. So a long pole struck upon gravel in the bottom of the water maketh a sound. Nay, if you should think that the sound cometh up by the pole, and not by the water, you shall find that an anchor let down by a rope maketh a sound and yet the rope is no solid body whereby the sound can ascend. Experiment solitary of the flight of the spirits upon odious objects. 793. All objects of the senses which are very offensive, do cause the spirits to retire: and upon their flight, the parts are, in some degree, destitute; and so there is induced in them a trepidation and horror. For sounds, we see that the grating of a saw, or any very harsh noise, will set the teeth on edge, and make all the body shiver. For tastes, we see that in the taking of a potion or pills, the head and the neck shake. For odious smells, the like effect followeth, which is less perceived, because there is a remedy at hand by stopping of the nose; but in horses, that can use no such help, we see the smell of a carrion, especially of a dead horse, maketh them fly away, and take on almost as if they were mad. For feeling, if you come out of the sun suddenly into a shade, there followeth a chilness or shivering in all the body. And even in sight, which hath in effect no odious object, coming into sudden darkness, induceth an offer to shiver. Experiment solitary touching the super-reflection of echos. 794. There is in the city of Ticinum in Italy, a church that hath windows only from above: it is in length an hundred feet, in breadth twenty feet, and in height near fifty; having a door in the midst. It reporteth the voice twelve or thirteen times, if you stand by the close end-wall over-against the door. The echo fadeth, and dieth by little and little, as the echo at Pont-Charenton doth. And the voice soundeth as if it came from above the door. And if you stand at the lower end, or on either side of the door, the echo holdeth; but if you stand in the door, or in the midst just over-against the door, not. Note, that all echos sound better against old walls than new; because they are more dry and hollow. Experiment solitary touching the force of imagination, 795. Those effects which are wrought by the percussion of the sense, and by things in fact, are produced likewise in some degree by the imagination. Therefore if a man see another eat sour or acid things, which set the teeth on edge, this object tainteth the imagination. So that he that seeth the thing done by another, hath his own teeth also set on edge. So if a man see another turn swiftly and long, or if he look upon wheels that turn, himself waxeth turn-sick. So if a man be upon an high place without rails or good hold, except he be used to it, he is ready to fall: for imagining a fall, it putteth his spirits into the very action of a fall. So many upon the seeing of others bleed, or strangled, or tortured, themselves are ready to faint, as if they bled, or were in strife. Experiment solitary touching preservation of bodies. 796. Take a stock-gilly-flower, and tie it gently upon a stick, and put them both into a stoop-glass full of quicksilver, so that the flower be covered: then lay a little weight upon the top of the glass that may keep the stick down; and look upon them after four or five days; and you shall find the flower fresh, and the stalk harder and less flexible than it was. If you compare it with another flower gathered at the same time, it will be the more manifest. This sheweth, that bodies do preserve excellently in quicksilver; and not pre serve only, but by the coldness of the quicksilver indurate; for the freshness of the flower may be merely conservation; which is the more to be observed, because the quicksilver presseth the flower; but the stiffness of the stalk cannot be without induration, from the cold, as it seemeth, of the quicksilver. Experiment solitary touching the growth or multiplying of metals. 797. It is reported by some of the ancients, that in Cyprus there is a kind of iron, that being cut into little pieces, and put into the ground, if it be well watered, will increase into greater pieces. This is certain, and known of old, that lead will multiply and increase, as hath been seen in old statues of stone which have been put in cellars; the feet of them being bound with leaden bands; where, after a time, there appeared, that the lead did swell; insomuch as it hanged upon the stone like warts. Experiment solitary touching the drowning of the more base metal in the more precious. 798. I call drowning of metals, when that the baser metal is so incorporate with the more rich, as it can by no means be separated again; which is a kind of version, though false: as if silver should be inseparably incorporated with gold: or copper and lead with silver. The ancient electrum had in it a fifth of silver to the gold, and made a compound metal, as fit for most uses as gold, and more resplendent, and more qualified in some other properties; but then that was easily separated. This to do privily, or to make the compound pass for the rich metal simple, is an adulteration or counterfeiting but if it be done avowedly, and with. out disguising, it may be a great saving of the richer metal. I remember to have heard of a man skilful in metals, that a fifteenth part of silver incorporated with gold will not be recovered by any water of separation, except you put a greater quantity of silver to draw to it the less which, he said, is the last refuge in separations. But that is a tedious way, which no man, 1 almost, will think on. This would be better inquired: and the quantity of the fifteenth turned to a twentieth; and likewise with some little additional, that may further the intrinsic incorporation. Note, that silver in gold will be detected by weight, compared with the dimension; but lead in silver, lead being the weightier metal, will not be detected, if you take so much the more silver as will countervail the over-weight of the lead. Experiment solitary touching fixation of bodies. 799. Gold is the only substance which hath nothing in it volatile, and yet melteth without much difficulty. The melting sheweth that it is not jejune, nor scarce in spirit. So that the fixing of it is not want of spirit to fly out, but the equal spreading of the tangible parts, and the close coacervation of them: whereby they have the less appetite, and no means at all to issue forth. It were good therefore to try, whether glass re-molten do lose any weight? for the parts in glass are evenly spread; but they are not so close as in gold; as we see by the easy admission of light, heat, and cold; and by the smallness of the weight. There be other bodies fixed, which have little or no spirit; so as there is nothing to fly out; as we see in the stuff whereof coppels are made, which they put into furnaces, upon which fire worketh not: so that there are three causes of fixation; the even spreading both of the spirits and tangible parts, the closeness of the tangible parts, and the jejuneness or extreme comminution of spirits of which three, the two first may be joined with a nature liquefiable, the last not. Experiment solitary touching the restless nature of things in themselves, and their desire to change. 800. It is a profound contemplation in nature, to consider of the emptiness, as we may call it, or insatisfaction of several bodies, and of their appetite to take in others. Air taketh in lights, and sounds, and smells, and vapours; and it is most manifest, that it doth it with a kind of thirst, as not satisfied with its own. former consistence; for else it would never receive them in so suddenly and easily. Water, and all liquors do hastily receive dry and more terrestrial bodies, proportionable: and dry bodies, on the other side, drink in waters and liquors: so that, as it was well said by one of the ancients, of earthy and watery substances, one is a glue to another. Parchment, skins, cloth, etc. drink in liquors, though themselves be entire bodies, and not comminuted, as sand and ashes, nor apparently porous metals themselves do receive in readily strong waters; and strong waters likewise do readily pierce into metals and stones: and that strong water will touch upon gold, that will not touch upon silver, and e converso. And gold, which seemeth by the weight to be the closest and most solid body, doth greedily drink in quicksilver. And it seemeth, that this reception of other bodies is not violent: for it is many times reciprocal, and as it were with consent. Of the cause of this, and to what axiom it may be referred, consider attentively; for as for the pretty assertion, that matter is like a common strumpet, that desireth all forms, it is but a wandering notion. Only flame doth not content itself to take in any other body, but either to overcome and turn another body into itself, as by victory; or itself to die, and go out. C. Baldwin, Printer, New Bridge-street, London. END OF VOL. I. |