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is That Mr. Hunter was also a man of constant and deep, reflection, that he possessed this enviable power of mind, so essential to the perfection of the intellectual character, is to me sufficiently apparent; for I, know of no opinion of his that was lightly or loosely formed, or that was not logically and cautiously deduced from the facts before him; and though from the subsequent, increase of knowledge, the validity of some of his opinions, may now be doubted, yet most of them have from the same cause become

more firmly established. With all his

genius, knowledge, and reflection, Mr. Hunter was not, however, a brilliant character amongst us. He had not the happy talent of displaying the stores of his mind, nor of communicating to others the same perception of the importance of his facts and opinions as he himself

entertained. Perhaps it may have arisen

from my attending more to his facts and opinions than to his mode of explaining them, that I have been led to form so high an estimate of his intellectual powers. I can draw no other inferences from the facts than those which he has drawn, and therefore am I a convert to his opinions. * o . . . . I proceed now to consider the structure and functions of those fibres which constitute the muscles, in order to introduce the discussion of the probability and rationality of Mr. Hunter's Theory as a cause of irritability. Muscular fibres are soft and readily lacerable in the dead body, and even during life when they are in a state of inaction. They are composed of that insoluble substance which we meet with in the blood, and which, from its disposition to concrete in a fibrous form, is called the fibrous part of that fluid. The threads and flakes of common cellular substance, which connect the muscular fibres, and every where pervade the structure of a muscle, may be removed by boiling, and then the muscular fibres may be separated, till they become too minute to admit of further separation, and almost elude our unassisted sight. Yet there are some who assert, that by the aid of powerful lenses each fibre, though slender as the threads of flimsy gossamer, appears but as a muscle in miniature, being composed of a number of smaller fibres. There are others who maintain, the contrary, and affirm that they can see the ultimate muscular fibres. It would seem to me a waste of time to detail to you the reports of various microscopical observers, respecting the ultimate fibres of muscles, since there is so little concurrence or certainty in their descriptions. The opinion which such contradictory statements have impressed

on my mind, is, that perhaps the ultimate arrangement of matter, like its ultimate particles, may form a subject too subtile for human perception. Our information in these respects must be limited, as our powers of perception have their bounds. The imperfection of the human senses does not, however, seem a subject of regret; because it induces a greater necessity for the exertions of intellect; and many subjects, appear far more demonstrable to reason than to sense.

Fontana, it must be granted, possessed considerable talent in microscopical observations, for he says, that he could readily distinguish the nature of any animal, substance, which might be placed on the field of his microscope, by regarding its ultimate fibres, and, according to, him the muscular fibres are much smaller than, those of the nerves. Proscaska and others

assert, that the ultimate muscular fibres are continued throughout the whole length of a muscle. How marvellous, (could we but see it,) would such a slender thread appear, continued throughout the whole length of the human sartorius. Haller, however, affirms, that the fibres are not continued, but that one set terminating another begins. Suspecting that Haller employed the solar microscope on this occasion, as he says he had done on others, I examined muscular fibres with this instrument. Now though I place no confidence in my own observation, and think the subject unimportant as to any conclusion, that may be deduced from it, yet I will tell you how a portion of a muscle, appeared to me: when magnified about 500 times. The fibres were slightly undulating, and one set terminating, another began: neither were the sets of fibres of considerable length. The mus

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