in feeling, willing, knowing, from a centre in the body but in as far as these conditions of soul are peculiar to itself as a soul, they are undefinable by any material analogy. But what is meant by the soul's operation from a centre will partly be seen from the anatomical fact, that all the nerves of sensation and voluntary action, as well as the brain, are connected and united in action together at a centre of junction at the base of the skull; and whatever breaks the connection with this point at once arrests both mental and vital action, for at this centre the soul acts on the body and the body on the soul.

The slightest examination of the organs of sense will convince an observer that they are constructed merely as instruments. What is the eye but a most perfect optical contrivance? It is composed of the fittest materials, arranged in the best manner, for the purpose of rendering illuminated objects not only visible, but tangible, for sight can be demonstrated to be a finer sort of feeling, the colours which represent distance and shape being brought in contact with the nerve and with that which perceives through the nerve. The cornea is a most perfect convex glass, set distinctly in its proper place and proper manner, with the same design—but with far greater precision-that the optician sets his crystal to aid the sight. The various translucent membranes, the lens, the humours of different densities, and even the blood, abruptly made transparent in its passage, and much besides too minute to be now mentioned, conspire to transmit, and duly refract, and regulate the rays of light, so that they may fall upon the exact point, and there present to the observant spirit a perfect photographic picture of the majestic, the beautiful, the glorious; and bring into our being those impressions which preserve our interest and sympathy with visible nature. No mechanism invented by man was ever so

well contrived or so well placed, or could move so precisely as required under the action of its pulleys. No servant was ever so obedient; for, without a conscious effort of the will, without a command, and as if instinct with the mind that employs it, this exquisite apparatus instantaneously takes the direction of a desire, and accommodates itself to the range of distance and the degree of light; being fitted, moreover, in its nervous structure to respond like a spirit, to the marvellous ethereal vibrations ranging probably from about 700 millions to 500 millions in a second, so that we obtain ideas of different colours, and link ourselves with the infinite diversities of the visible universe.

And the ear is a complete acoustic instrument, with its exterior trumpet to collect sounds, and its vibrating tympanum, and its chamber and winding passages, and its dense fluids, so well calculated to propagate and modify vibrations, and its minute and sensitive muscles, to act as cords to brace the drum just as required, and move the jointed piston, which regulates the water in its canals according to circumstances, and the whole built up within a stone-like structure which prevents the sound from being wasted. How complicated and delicate must be the mechanism of the ear, in order that the nerves floating in the fluid of its cavities should vibrate in unison with sounds varying from 14 undulations to 48,000 in a second! The resonant vibrations of air first fall on the tympanic membrane which closes the external orifice of the ear, and separates it from the cavity called the drum of the ear. This cavity is also separated from the channels to the brain by a bony partition which has two orifices in it, the one oval and the other round. These are closed by fine membranes. Four minute bones stretch across the cavity of the drum, the first of which, called the hammer, is attached to the tympanic membrane; the second, named

the anvil, is connected by a joint with the hammer; the third, a round bone about the size of a pin's head, connects the anvil with the fourth or the stirrup bone, so called from its shape. The oval base of the stirrup bone rests against the membrane of the oval orifice in the bony partition, not covering it, but leaving a narrow rim of the membrane surrounding the bone. This jointed arrangement of little bones serves to convey the vibrations impressed by the air on the tympanic membrane to the bony partition between the drum and the brain. In this bony partition we have that wonderful organ called the labyrinth, which is filled with water, and over the lining of which the delicate fibres of the auditory nerve are arranged. Thus the vibrations of the air are not received in a direct manner on the nervefibres, but are transferred under a regulated influence which acts on the muscles moving the fine chain of bones between the tympanic membrane and the labyrinth. In the labyrinth itself also, there are exquisite arrangements to modify the impression of the sonorous vibrations, and fit them for transmission through the nerve-fibres to the brain and the mind. Exceedingly fine elastic bristles, having sharp points, grow up between the terminal fibres of nerve. These bristles receive the vibrations, through the medium of the water in the labyrinth, and act upon the nerve-fibres at their roots, thus exciting the auditory sensations. There are also in the labyrinth a number of microscopic crystalline particles (otolithes) embedded among the nervous filaments, which exert an intermittent pressure upon those filaments, and thus prolong the vibrations of sounds that might otherwise escape attention. Finally, there is in the labyrinth a marvellous musical instrument, an actual lute of 3,000 strings,* so stretched as to accept vibrations

* Marchese Corti discovered this organ, and Kölliker counted its fibres.

of different periods, and transmit them to the nervefilaments. Thus each musical tremor which falls upon this organ, selects from its tensioned fibres the one appropriate to its own pitch, and throws that fibre into unisonant vibration. And thus, no matter how complicated the motion of the external air may be, those microscopic strings can analyse it and reveal the constituents of which it is composed' ('Tyndall on Sound,' p. 325). There is much of wisdom in the arrangement of the ear, as indeed in all the other organs also, the meaning of which human sagacity cannot discover; this much, however, can always be ascertained: the purpose is, to bring the mind into contact with that whence flows its experience, and which excites its emotions.

The senses, moreover, correspond together, and thus enable the mind to correct the impressions of one by those of the others in such a manner as, by their united operation, to obtain full and accurate intelligence concerning the surrounding world.

The well-known case which the philosophic Cheselden has related, affords a decisive experiment, agreeing as it does with many others, in proof that the information derived from the sense of sight requires to be corrected by information from different sources; but that when the habit of seeing is established under this correction, vision continues to suggest the true relations of objects to each other.

A young gentleman who had no remembrance of ever having seen, was couched, and received his sight; when he first saw, however, he could not judge of distances, but thought all visible objects touched his eye, as what he felt touched his skin. He expected that pictures would feel like what they represented; and was amazed when he found those parts which by light and shadow appeared round and uneven, felt flat like the rest, and asked which was the lying sense, feeling or sight. When

shown a miniature of his father, he acknowledged the likeness, but desired to know how so large a face could be expressed in so small a compass, saying it seemed as impossible to him as to put a bushel into a pint. The things he first saw he thought extremely large; and upon seeing larger things, those first seen he conceived less, not being able to imagine any lines beyond the bounds he beheld. He could not conceive that the house could look larger than the room he was in. He said every new object was a new delight. On first beholding a large prospect, his pleasure was beyond expression, and he called it a new kind of seeing. It was an extension of his own existence and capacity. Seeing is in fact the true type of all perception and knowledge, for the soul's growth is but enlargement in the experience of what light, both material and mental, reveals.

These details prove that sight does not originally inform us respecting the real distance or magnitude of objects, but that we learn these things from the impressions also made upon our other senses; therefore, the mind exercises an independent judgment in comparing their impressions, really a soul-power which the senses themselves could never have conferred. The faculty of comparison, indeed, implies the operation of an attending, remembering agent, endowed with an intuitive. perception of differences, and capable of detaining ideas before the eye of the mind, and regarding them in their mutual relations. In short, since we use our senses we have proof of our spiritual being, and that the organs of sense are means by which we test the properties of things by their influence on ourselves as spiritual agents.

To understand our connection with the sense-organs we must study the co-operation of sense with sense, not only as they excite one another and administer to our apprehension and appreciation of outward things, but also as the means of awakening our faculties and affec