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CHAP. III.

heated; or from the rocking of a cradle, PART I or the gentle motion of a boat, or easy carriage, after having been fatigued with violent Of Touch. exercise. Such, too, is that which twilight, or the gloomy shade of a thicket, affords to the eye, after it has been dazzled with the blaze of the mid-day sun; and such, likewise, is that, which the ear receives, from the gradual diminution of loudness of tone in music; and it is by alternately ascending and descending this scale, that what is called (by a metaphor taken from painting) the chromatic in that art, is produced: but why the sensation caused by the ascent of the scale should be called pleasure, and that caused by its descent, delight, as distinguished by an eminent writer*, I cannot discover.

Sublime and Beautiful, P. I. s. iv,

PART I.

CHAP. IV.

Of Hearing.

CHAPTER IV.

OF HEARING,

1. SOUND is produced by the vibrations of elastic air or some other fluid contained in it, and communicated to the interior organs of perception by means of the drum of the ear and auditory nerves; which are formed by nature with a peculiar kind of irritability suited to such vibrations, which have no effect on any other part of the body, how exquisite soever its sensibility may be. They have, nevertheless, a very strong and marked effect upon the hardest substances in nature, provided they are such as are capable of receiving vibrations in unison: whence sound will break a glass, at the same time, that it cannot move a feather or the flame of a candle; nor make any perceptible impression upon the ball of the eye.

2. Its vibrations, indeed, seem to be communicable to every hard and elastic substance; as appears from the ticking of a watch, or any other minute sound being conveyed to almost any distance by a pole or wire

sonorous object to the ear.

extending from the Where the drum of

that organ, too, is diseased; and the sense of PART I. hearing consequently lost or impaired, the low

CHAP. IV.

est whisper will, nevertheless, be distinctly of Hearing. heard, if spoken to one end of a bar of metal or glass, while the other is held between the teeth of the person addressed: but if the disease extends to the auditory nerves; so as to deprive them of their irritability, nothing can be heard by these or any other means. The sound, therefore, appears, in this instance, to be conveyed to those nerves, which communicate with the brain, by means of vibrations received by one solid and elastic substance from another; and thus continued through the bar, the teeth, and the jaw bones.

3. Many of these solid bodies, which are so susceptible of the vibrations of sound, such as glass, and different kinds of metal, are impenetrable to air: wherefore I suspect that sound is produced by some finer fluid mixed with air; and pervading elastic, as light does transparent bodies. Of this fluid, however, if such there. be, we can never obtain any adequate knowledge: for, as it is only perceived, as the vehicle of impressions to one sense, our ideas of it must always remain in nearly the same state as those which a man born blind can form of the light of the sun by feeling its warmth. That hard

CHAP. IV.

Of Hearing.

PART Í. and solid substances should transmit this light, which is excluded by the most soft and porous, is equally unaccountable, as that they should transmit sound. In both, probably, there is a peculiar distribution of the component particles, respectively adapted to the admission of a particular fluid, and of that only.

4. But whatever be the nature of the substance, which produces sound, the sensations, caused by its vibrations upon the organs of hearing, will depend upon the same principles, as those produced by other substances on other organs. Certain modes and degrees of irritation will be pleasant, others painful, and others insipid; and these will vary in different individuals according to the different degrees of sensibility in their respective organs. In some sorts of dogs, this sensibility is so exquisite, that the sound of a fife or other very shrill instrument, though perfectly in harmony, gives them very acute pain, when near to their ears; as they testify by loud howlings and complainings. The filing of a saw, or other harsh and discordant sound of that kind, though not loud, will create a very uneasy and even painful sensation in the human organs, which we commonly call setting the teeth on edge; and it seems to be produced by extending the vibrations from the ears to the teeth, in

CHAP. IV.

stead of from the teeth to the ears: as in the ex- PART I. periment of the metal or glass bar before cited. Extremely loud and jarring sounds, such as those of Hearing. of kettle-drums or artillery, will extend this vibration through the whole body; as I very sensibly felt at the performance of some of Handel's choruses in Westminster Abbey: but, as they were in harmony, the sensation was not at all unpleasant. On the contrary, if I could conceive any sensation to be sublime, I should admit this to be so: but the sentiment of sublimity belongs to the affections of the mind, and not to organic sensation; as I shall fully show in examining that part of my subject.

5. The sensual pleasures of sound, to which I wish at present to confine my inquiries, are in their modes and progress nearly analogous to those of taste. Very young persons almost always prefer the sweet tones of a flute, or the female human voice, unaccompanied and without any technical modulation, to any more complicated harmony: but these simple tones, by being often repeated with little variety, grow vapid and tiresome; while mixtures, when once the relish for them is acquired, give permanent pleasure by varying it through every possible mode of combination; and still further varying these modes of combination by all the diversities

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