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281. THE experiment of sympathy may be transferred, perhaps, from instruments of strings to other instruments of sound. As to try, if there were in one steeple two bells of unison, whether the striking of the one would move the other, more than if it were another accord: and so in pipes, if they be of equal bore and sound, whether a little straw or feather would move in the one pipe, when the other is blown at a unison.

282. It seemeth, both in ear and eye, the instrument of sense hath a sympathy or similitude with that which giveth the reflection, as hath been touched before: for as the sight of the eye is like a crystal, or glass, or water; so is the ear a sinuous cave, with a hard bone to stop and reverberate the sound: which is like to the places that report echos..

Experiments in consort touching the hindering or helping of the hearing.

283. When a man yawneth, he cannot hear so well. The cause is, for that the membrane of the ear is extended; and so rather casteth off the sound than draweth it to.

284. WE hear better when we hold our breath than contrary insomuch as in all listening to attain a sound afar off men hold their breath. The cause is, for that in all expiration the motion is outwards; and therefore rather driveth away the voice than draweth it: and besides we see, that in all labour to do things with any strength, we hold the breath; and listening after any sound that is heard with difficulty, is a kind of labour.

285. LET it be tried, for the help of the hearing, and I conceive it likely to succeed, to make an instrument like a tunnel; the narrow part whereof may be of the bigness of the hole of the ear; and the broader end much larger, like a bell at the skirts; and the length half a foot or more. And let the narrow end of it be set close to the ear: and mark whether any sound, abroad in the open air, will not be heard distinctly from farther distance, than without

that instrument; being, as it were, an ear-spectacle. And I have heard there is in Spain an instrument in use to be set to the ear, that helpeth somewhat those that are thick of hearing.

286. Ir the mouth be shut close, nevertheless there is yielded by the roof of the mouth a murmur; such as is used by dumb men. But if the nostrils be likewise stopped, no such murmur can be made: except it be in the bottom of the palate towards the throat. Whereby it appeareth manifestly, that a sound in the mouth, except such as aforesaid, if the mouth be stopped, passeth from the palate through the nostrils.

Experiments in consort touching the spiritual and fine nature of sounds.

287. THE repercussion of sounds, which we call echo, is a great argument of the spiritual essence of sounds. For if it were corporeal, the repercussion should be created in the same manner, and by like instruments, with the original sound: but we see what a number of exquisite instruments must concur in speaking of words, whereof there is no such matter in the returning of them, but only a plain stop and repercussion.

288. THE exquisite differences of articulate sounds, carried along in the air, shew that they cannot be signatures or impressions in the air, as hath been well refuted by the ancients. For it is true, that seals make excellent impressions; and so it may be thought of sounds in their first generation: but then the delation and continuance of them without any new sealing, shew apparently they cannot be impressions.

289. ALL sounds are suddenly made, and do suddenly perish: but neither that, nor the exquisite differences of them, is matter of so great admiration: for the quaverings and warblings in lutes and pipes are as swift; and the tongue, which is no very fine instrument, doth in speech make no fewer motions than there be letters in all the words which are uttered. But that sounds should not only be so speedily generated, but carried so far every way in such a moment

any time, deserveth more admiration. As for example, if a man stand in the middle of a field and speak aloud, he shall be heard a furlong in round; and that shall be in articulate sounds; and those shall be entire in every little portion of the air; and this shall be done in the space of less than a minute.

290. THE sudden generation and perishing of sounds, must be one of these two ways. Either that the air suffereth some force by sound, and then restoreth itself, as water doth; which being divided, maketh many circles, till it restore itself to the natural consistence or otherwise, that the air doth willingly imbibe the sound as grateful, but cannot maintain it; for that the air hath, as it should seem, a secret and hidden appetite of receiving the sound at the first; but then other gross and more materiate qualities of the air straightways suffocate it; like unto flame, which is generated with alacrity, but straight quenched by the enmity of the air or other ambient bodies.

There be these differences, in general, by which sounds are divided: 1. Musical, immusical. 2. Treble, base. 3. Flat, sharp. 4. Soft, loud. 5. Exterior, interior. 6. Clean, harsh or purling. 7. Articulate, inarticulate.

We have laboured, as may appear, in this inquisition of sounds diligently; both because sound is one of the most hidden portions of nature, as we said in the beginning, and because it is a virtue which may be called incorporeal and immateriate; whereof there be in nature but few. Besides, we were willing, now in these our first centuries, to make a pattern or precedent of an exact inquisition; and we shall do the like hereafter in some other subjects which require it. For we desire that men should learn and perceive, how severe a thing the true inquisition of nature is; and should accustom themselves by the light of particulars to enlarge their minds to the amplitude of the world, and not reduce the world to the narrowness of their minds.

Experiment solitary touching the orient colours in dissolution of metals.

291. METALS give orient and fine colours in dissolutions; as gold giveth an excellent yellow; quicksilver an excellent green; tin giveth an excellent azure: likewise in their putrefactions or rusts; as vermilion, verdigrease, bise, cirrus, etc. and likewise in their vitrifications. The cause is, for that by their strength of body they are able to endure the fire or strong waters, and to be put into an equal posture; and again to retain part of their principal spirit: which two things, equal posture and quick spirits, are required chiefly to make colours lightsome.

Experiment solitary touching prolongation of life. 292. IT conduceth unto long life, and to the more placid motion of the spirits, which thereby do less prey and consume the juice of the body, either that men's actions be free and voluntary, that nothing be done invita Minerva, but secundum genium; or on the other side, that the actions of men be full of regulation and commands within themselves: for then the victory and performing of the command giveth a good disposition to the spirits; especially if there be a proceeding from degree to degree; for then the sense of the victory is the greater. An example of the former of these is in a country life; and of the latter in monks and philosophers, and such as do continually enjoy themselves.

Experiment solitary touching appetite of union

in bodies.

293. IT is certain that in all bodies there is an appetite of union and evitation of solution of continuity and of this appetite there be many degrees; but the most remarkable and fit to be distinguished are three. The first in liquors; the second in hard bodies; and the third in bodies cleaving or tenacious. In liquors this appetite is weak: we see in liquors, the threading of them in stillicides, as hath been said; the falling of them in round drops, which is the form

of union; and the staying of them for a little time in bubbles and froth. In the second degree or kind, this appetite is strong; as in iron, in stone, in wood, etc. In the third, this appetite is in a medium between the other two: for such bodies do partly follow the touch of another body, and partly stick and continue to themselves; and therefore they rope, and draw themselves in threads; as we see in pitch, glue, birdlime, etc. But note, that all solid bodies are cleaving more or less: and that they love better the touch of somewhat that is tangible, than of air. For water in small quantity cleaveth to any thing that is solid; and so would metal too, if the weight drew it not off. And therefore gold foliate, or any metal foliate, cleaveth but those bodies which are noted to be clammy and cleaving, are such as have a more indifferent appetite at once to follow another body, and to hold to themselves. And therefore they are commonly bodies ill mixed; and which take more pleasure in a foreign body, than in preserving their own consistence; and which have little predominance in drought or moisture.

Experiment solitary touching the like operations
of heat and time.

294. TIME and heat are fellows in many effects. Heat drieth bodies that do easily expire; as parchment, leaves, roots, clay, etc. And so doth time or age arefy; as in the same bodies, etc. Heat dissolveth and melteth bodies that keep in their spirits; as in divers liquefactions: and so doth time in some bodies of a softer consistence, as is manifest in honey, which by age waxeth more liquid, and the like in sugar; and so in old oil, which is ever more clear and more hot in medicinable use. Heat causeth the spirits to search some issue out of the body; as in the volatility of metals; and so doth time; as in the rust of metals. But generally heat doth that in small time which age doth in long.

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