a

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 bath, 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

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.

Experiment solitary touching the differing opera

tions of fire and time. 295. Some things which pass the fire are softest at first, and by time grow hard, as the crumb of bread. Some are harder when they come from the fire, and afterwards give again, and grow soft, as the crust of bread, biscuit, sweetmeats, salt, etc. The cause is, for that in those things which wax hard with time, the work of the fire is a kind of melting; and in those that wax soft with time, contrariwise, the work of the fire is a kind of baking; and whatsoever the fire baketh, time doth in some degree dissolve. Experiment solitary touching motions by imitation.

296. Motions pass from one man to another, not so much by exciting imagination as by invitation ; especially if there be an aptness or inclination before. Therefore gaping, or yawning, and stretching do pass from man to man; for that that causeth gaping and stretching is, when the spirits are a little heavy by any vapour, or the like. For then they strive, as it were, to wring out and expel that which loaded them. So men drowsy, and desirous to sleep, or before the fit of an ague, do use to yawn and stretch; and do likewise yield a voice or sound, which is an interjection of expulsion : so that if another be apt and prepared to do the like, he followeth by the sight of another. So the laughing of another maketh to laugh.

Experiment solitary touching infectious diseases. · 297. THERE be some known diseases that are infectious; and others that are not. Those that are infectious are, first, such as are chiefly in the spirits, and not so much in the humours; and therefore pass easily from body to body; such are pestilences, lippitudes, and such like. Secondly, such as taint the breath, which we see passeth manifestly from man to man; and not invisibly, as the affects of the spirits do; such are consumptions of the lungs, etc. Thirdly, such as come forth to the skin, and therefore taint the air or the body adjacent; especially if they consist

in an unctuous substance not apt to dissipate; such are scabs and leprosy. Fourth]y, such as are merely in the humours, and not in the spirits, breath, or exhalations; and therefore they never infect but by touch only; and such a touch also as cometh within the epidermis ; as the venom of the French pox, and

, the biting of a mad dog. Experiment solitary touching the incorporation

of powders and liquors. 298. Most powders grow more close and coherent by mixture of water, than by mixture of oil, though oil be the thicker body; as meal, etc. The reason is the congruity of bodies; which if it be more, maketh a perfecter imbitition and incorporation; which in most powders is more between them and water, than between them and oil : but painters' colours ground, and ashes, do better incorporate with oil. Experiment solitary touching exercise of the body.

299. Much motion and exercise is good for some bodies; and sitting and less motion for others. If the body be hot and void of superfluous moistures, too much motion hurteth: and it is an error in physicians, to call too much upon exercise. Likewise men ought to beware, that they use not exercise and a spare diet both: but if much exercise, then a plentiful diet; and if sparing diet, then little exercise. The benefits that come of exercise are, first, that it sendeth nourishment into the parts more forcibly. Secondly, that it helpeth to excern by sweat, and so maketh the parts assimilate the more perfectly. Thirdly, that it maketh the substance of the body more solid and compact; and so less apt to be consumed and depredated by the spirits. The evils that come of exercise are, first, that it maketh the spirits more hot and predatory. Secondly, that it doth absorb likewise, and attenuate too much the moisture of the body. Thirdly, that it maketh too great concussion, especially if it be violent, of the inward parts, which delight more in rest. But generally exercise,