The Book of Curiosities

by John Platts

————————The visual orbs
Remark, how aptly station’d for their task;
Rais’d to th’ imperial head’s high citadel,
A wide extended prospect to command.
See the arch’d outworks of impending lids,
With hairs, as palisadoes fenc’d around
To ward annoyance from without.
Bally.

Again:—

Who form’d the curious organ of the eye,
And cloth’d it with its various tunicles,
Of texture exquisite; with crystal juice
Supply’d it, to transmit the rays of light;
Then plac’d it in its station eminent,
Well fenc’d and guarded, as a centinel
To watch abroad, and needful caution give?
Needler.

The next subject is, The Curious Structure of the Ear.

The channel’d ear, with many a winding maze,
How artfully perplex’d, to catch the sound.
And from her repercussive caves augment!
Bally.
Dark night, that from the eye his function takes,
The ear more quick of apprehension makes;
Wherein it doth impair the seeing sense,
It pays the Hearing—double recompense.
Shakspeare.

Although the ear, with regard to beauty, yields to the eye, its conformation is not less perfect, nor less worthy of the Creator. The position of the ear bespeaks much wisdom; for it is placed in the most convenient part of the body, near to the brain, the common seat of all the senses. The exterior form of the ear merits considerable attention; its substance is between the flexible softness of flesh, and the firmness of bone, which prevents the inconvenience that must arise from its being either entirely muscular or wholly formed of solid bone. It is therefore cartilaginous, possessing firmness, folds, and smoothness, so adapted as to reflect sound; for the chief use of the external part is to collect the vibrations of the air, and transmit them to the orifice of the ear. The internal structure of this organ is still more remarkable. Within the cavity of the ear is an opening, called the meatus auditorius, or auditory canal, the entrance to which is defended by small hairs, which prevent insects and small particles of extraneous matter penetrating into it; for which purpose there is also secreted a bitter ceruminous matter, called ear-wax. The auditory canal is terminated obliquely by a membrane, generally known by the name of drum, which instrument it in some degree resembles; for within the cavity of the auditory canal is a kind of bony ring, over which the membrana tympani is stretched. In contact with this membrane, on the inner side, is a small bone (malleus) against which it strikes when agitated by the vibrations of sound. Connected with these are two small muscles: one, by stretching the membrane, adapts it to be more easily acted upon by soft and low sounds; the other, by relaxing, prepares it for those which are very loud. Besides the malleus, there are some other very small and remarkable bones, called incus, or the anvil, as orbiculare, or orbicular bone, and the stapes, or stirrup: their use is, to assist in conveying the sounds received upon the membrana tympani. Behind the cavity of the drum, is an opening, called the Eustachian tube, which begins at the back part of the mouth with an orifice, which diminishes in size as the tube passes towards the ear, where it becomes bony; by this means, sounds may be conveyed to the ear through the mouth, and it facilitates the vibrations of the membrane by the admission of air. We may next observe the cochlea, which somewhat resembles the shell of a snail, whence its name; its cavity winds in a spiral direction, and is divided into two by a thin spiral lamina: and lastly is the auditory nerve, which terminates in the brain. The faculty of hearing is worthy of the utmost admiration and attention: by putting in motion a very small portion of air, without even being conscious of its moving, we have the power of communicating to each other our thoughts, desires, and conceptions. But to render the action of air in the propagation of sound more intelligible, we must recollect that the air is not a solid, but a fluid body. Throw a stone into a smooth stream of water, and there will take place undulations, which will be extended more or less according to the degree of force with which the stone was impelled. Conceive then, that when a word is uttered in the air, a similar effect takes place in that element, as is produced by the stone in the water. During the action of speaking, the air is expelled from the mouth with more or less force; this communicates to the external air which it meets, an undulatory motion; and these undulations of the air entering the cavity of the ear, the external parts of which are peculiarly adapted to receive them, strike upon the membrane, or drum, by which means it is shaken, and receives a trembling motion: the vibration is communicated to the malleus, the bone immediately in contact with the membrane, and from it to the other bones; the last of which, the stapes or stirrup, adhering to the fenestra ovalis, or oval orifice, causes it to vibrate; the trembling of which is communicated to a portion of water contained in the cavity called the vestibulum, and in the semicircular canals, causing a gentle tremor in the nervous expansion contained therein, which is transmitted to the brain; and the mind is thus informed of the presence of sound, and feels a sensation proportioned to the force or to the weakness of the impression that is made. Let us rejoice that we possess the faculty of hearing; for without it, our state would be most wretched and deplorable; in some respects, more sorrowful than the loss of sight; had we been born deaf, we could not have acquired knowledge sufficient to enable us to pursue any art or science. Let us never behold those who have the misfortune to be deaf, without endeavoring better to estimate the gift of which they are deprived, and which we enjoy; or without praising the goodness of God, which has granted it to us: and the best way we can testify our gratitude is, to make a proper use of this important blessing.

We now proceed to a more particular description of The Curiosities of the Human Heart; and the Circulation of the Blood.

———Though no shining sun, nor twinkling star
Bedeck’d the crimson curtains of the sky;
Though neither vegetable, beast, nor bird,
Were extant on the surface of this ball,
Nor lurking gem beneath; though the great sea
Slept in profound stagnation, and the air
Had left no thunder to pronounce its Maker:
Yet Man at home, within himself might find
The Deity immense, and in that frame
So fearfully, so wonderfully made!
See and adore his providence and power.
Smart.

With what admirable skill and inimitable structure is formed that muscular body, situated within the cavity of the chest, and called the human heart! Its figure is somewhat conical, and it is externally divided into two parts: the base, which is uppermost, and attached to vessels; and the apex, which is loose and pointing to the left side, against which it seems to beat. Its substance is muscular, being composed of fleshy fibres, interwoven with each other. It is divided internally into cavities, called auricles and ventricles; from which vessels proceed to convey the blood to the different parts of the body. The ventricles are situated in the substance of the heart, and are separated from each other by a thick muscular substance; they are divided into right and left, and each communicates with its adjoining auricle, one of which is situated on each side the base of the heart. The right auricle receives the blood from the head and superior parts of the body, by means of a large vein; and in the same manner the blood is returned to it from the inferior parts, by all the veins emptying their stores into one, which terminates in this cavity; which, having received a sufficient portion of blood, contracts, and by this motion empties itself into the right ventricle, which also contracting, propels the blood into an artery, which immediately conveys it into the lungs, where it undergoes certain changes, and then passes through veins into the left auricle of the heart, thence into the left ventricle, by the contraction of which it is forced into an artery, through whose ramifications it is dispersed to all parts of the body, from which it is again returned to the right auricle; thus keeping up a perpetual circulation, for, whilst life remains, the action of the heart never ceases. In a state of health the heart contracts about seventy times in a minute, and is supposed, at each contraction, to propel about two ounces of blood; to do which, the force it exerts is very considerable, though neither the quantity of force exerted, nor of blood propelled, is accurately determined. The heart comprises within itself a world of wonders, and whilst we admire its admirable structure and properties, we are naturally led to consider the wisdom and power of Him who formed it, from whom first proceeded the circulation of the blood, and the pulsations of the heart; who commands it to be still, and the functions instantly cease to act.

This important secret of the circulation of blood in the human body was brought to light by William Harvey, an English physician, a little before the year 1600: and when it is considered thoroughly, it will appear to be one of the most stupendous works of Omnipotence.