might be continually in a state of enjoyment, and that when urged by necessities such as thirst, hunger, and weariness, they might merely feel a diminution of pleasure, is to suppose not only their nature, but that of the external world, altered. Whilst earth, rocks, woods, and water are the theatre of our existence, the textures of our bodies must be exposed to injuries: and they can only be protected from them by sensibilities adapted to each part, and capable of rousing us to the most animated exertions. To leave us to the guidance of the solicitations of pleasure, would be to place us where accident would befall us at every step; and whether these injuries were felt or not, they would be destructive to life.

In short, to suppose that we might move and act without experience of resistance or of pain, that there should be nothing to bruise the skin, or hurt the eye, and nothing noxious to be inhaled with the breath, would be to imagine another state of existence altogether from the present; and the theorist would be mortified were that interpretation put on his meaning. Pain is the necessary contrast to pleasure: it ushers us into existence, and is the first to give us consciousness: it alone is capable of exciting the organs into activity: it is the companion and the guardian of human life. If all were smooth in our path, if there were neither rugged places nor accidental opposition, whence should we derive those affections of our minds which we call enterprise, fortitude, and patience?

Independently of pain, which protects us more powerfully than a shield, there is inherent in us, and for a similar purpose, an innate horror of death. "And what thinkest thou," said Socrates to Aristodemus, "of this continual love of life, this dread of dissolution, which takes possession of us from the moment we are conscious of existence?" "I think of it," answered he, "as the means employed by the same great and wise artist, deliberately determined, to preserve what he has made." The reader will, no doubt, observe here the distinction. We have experience of pain from injuries, and we learn to avoid them. But we can have no experience of death. Therefore the Author of our being has implanted in us an innate horror at dissolution; and we may see the same principle extending through all animated nature. Where it is possible to be taught by experience, we are left to profit by it; but where

we can have none, feelings are engendered without it. And this is all that was necessary to show how the life is guarded; sometimes it is by mechanical strength, as in the skull; sometimes by acute sensation, as in the skin and in the eye; sometimes by innate affections of the mind, as in the horror of death: and these will prevail, as the voice of nature, when we can no longer profit by experience.

The highest proof of benevolence is this: that we possess the chiefest source of happiness in ourselves. Every creature has pleasure in the mere exercise of his body, as well as in the languor and repose that follow exertion. But these conditions are so balanced, that we are impelled to change; and every change is an additional source of enjoyment. What is apparent in the body is true of the mind also. The great source of happiness is to be found in the exercise of talents; and perhaps the greatest of all is when the ingenuity of the mind is exercised in the dexterous employment of the hands. Idle men do not know what is meant here; but nature has implanted in us this stimulus to exertion; so that the ingenious artist who invents, or with his hands creates, enjoys a source of delight, perhaps greater, certainly more uninterrupted, than belongs to the possession of higher intellectual powers; far at least beyond what falls to the lot of the mere minion of fortune.

CHAPTER VIII.

OF THE SENSES GENERALLY, INTRODUCTORY TO THE SENSE OF TOUCH.

ALTHOUGH We are most familiar with the sensibility of the skin, and believe that we perfectly understand the nature and mode of conveyance of the impressions received upon it to the sensorium, yet there is a difficulty in comprehending the operations of the other organs of the senses—a difficulty not removed by the apparent simplicity of that of touch.

But

There was a time when the inquirer was satisfied by finding in the ear a little drum, and a bone to play upon it, with an accompanying nerve; this was deemed a sufficient explanation of the organ of hearing. It was thought equally satisfactory if, in experimenting upon the eye, the image of the object were seen painted at the bottom, on the surface of the nerve. although the impression can be thus traced to the extremity of the nerve, still nothing is comprehended of the nature of that impression, or of the manner in which it is transmitted to the sensorium. On the most minute examination of the nerves, in all their course, and where they are expanded in the external organs of the senses, they seem to be the same in substance and in structure, whatever be their function. Whether the disturbance of the extremity of the nerve that gives rise to the sensation, be a vibration, or an image painted upon the surface, it cannot, in either case, be transmitted to the brain according to any physical laws that we are acquainted with. All that we can say is, that the different affections of the nerves of the outward senses, are the signals which the Author of nature has willed to be the means by which correspondence is held with the realities. The impression on the nerve can have no more resemblance to the ideas suggested in the mind, than there is between the sound and the conception, in the mind of that man who, looking out on a dark and stormy sea, hears the report of can

non, which conveys to him ideas of despair and shipwreck—or between the light received into the eye, and the idea excited in one who, apprehending national convulsion, sees a column of flame afar off, which to him is the signal of actual revolt.

Such illustrations, it may be said, rather tend to show how independent the mind is of the organs of the senses. That a tumult of ideas should arise from an impression on the retina, not more intense than that produced by a burning taper, may be regarded as an instance of excited imagination. But even in a common act of perception, the determined relations between the sensation and the idea in the mind have no more actual resemblance. How this consent, so precise and constant, is established, can neither be explained by physiology nor any mode of physical inquiry whatever.

From this law of our nature, that certain perceptions originate in the mind in consequence of the impressions on corresponding nerves, it follows, that one organ of sense can never become the substitute for another, so as to excite the same ideas. When an individual is deprived of the organs of sight, no power of attention, or continued effort of the will, or exercise of the other senses, can enable him to enjoy the class of sensations which is lost. The sense of touch may have its delicacy increased in an exquisite degree; but if it be true, as has been asserted, that individuals can distinguish colours by touch, it can only be by their feeling a change upon the surface of the stuff, and not by any perception of the colour. It has been my painful duty to attend on persons who have feigned blindness, and pretended that they could see with their fingers: but I have ever found that these first deviations from truth entangled them in a tissue of deceit; and they have at last been forced into admissions which showed their folly and weak inventions. When such patients were affected with nervous disorders, producing extraordinary sensibility in their organs, -as a power of hearing much beyond our common experience,—they became objects of pity; this acuteness of sensibility, from its exciting interest and wonder, has gradually led these morbidly-affected persons to pretend to powers greater than they actually possessed; and it has been difficult to distinguish the symptoms of disease, from the supposed gifts of which they boasted.

Experiment proves, as we have already stated, that each organ

of sense is appropriated to receive a particular kind of sensation only; and that the nerves intermediate between the brain and the outward organs respectively, are capable of receiving no other sensations but such as are proper to their particular organs. Every impression on the nerve of the eye, or of the ear, or of smelling, or of taste, excites only perceptions of vision, of hearing, of smelling, or of taste; not simply because the extremities of these nerves individually are suited to one kind of external impression; but because the nerves, through their whole course, and wherever they are affected, are capable of communicating the idea to which they are appropriated, and no other. A blow on the head, an impulse quite unlike that for which the organs of the senses are provided, will excite them all in their several ways; besides the pain, there will be sparks of fire in the eyes, and a loud noise in the ears. An officer received a musketball which went through the bones of his face-in describing his sensations, he said that he felt as if there had been a flash of lightning, accompanied with a sound like the shutting of the door of St Paul's.

It is owing to the circumstance of every nerve being appropriated to its function, that the false sensations which accompany the morbid irritation of the nerves from internal causes, are produced-such as flashes of light, ringing of the ears, bitter tastes, or offensive smells. These sensations are caused by derangement of some internal organ, most frequently the stomach, exciting the respective nerves of sense.

Nothing affords a more perfect proof of power and design, than the confidence all men put in the correspondence between the perceptions or ideas that arise in the mind, through the exercise of the organs of the senses, and the qualities of external matter. Although it must ever be beyond our comprehension, how the object presented to the outward sense and the idea of it are connected, they are, nevertheless, indissolubly united; so that the knowledge of the object, gained by these unknown means, is attended with an absolute conviction of the real existence of the object—a conviction independent of reason, and to be regarded as a first law of our nature.

In the percipient or sentient principle residing in the brain and nerves, as well as in the organs of sense, there must be a conformity to the impression, and a correspondence with the