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from a nervous packet, in the manner. before mentioned, though “too minute to: admit of further subdivision, appearby. the microscope to be themselves packets. of smaller threads. It is generally asserted by microscopical observers, that the nerves and medullary matter of the brain and spinal marrow are the same, and are composed of very minute fibres. Fontana speaks confidently on this point; and he further says, that he has seen these nervous: fibres regenerated in the medium which has been formed to unite a divided; nerve. o. He describes the “nervous fibres, in every part of the nervous system as cylindrical, pursuing a slightly undulating course,” and being in a considerable degree transparent. He states also that they are larger than the ultimate fibres of muscles.

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Microscopical observers also tell us, that

obtained the title of the great sympathetis 1262FWe. - -

The vital organs are required to carry on their functions with a degree of regularity and order, under the varying circumstances of life; and the possession of a distinct nerve may enable them to continue their functions without so materially participating in the disturbances of the animal system, as they must otherwise have done : yet the numerous connections of the visceral with the animal nerves must render both participators in each other's disorders. . .

The nerves, then, may be said to proceed from the brain, medulla spinalis, and visceral nerve, to all parts of the body for their supply. In thus expressing” a fact, however, we should guard againstan idea which the analogous distribution of arteries is apt to lengender. ...Arteries become minute in proportion as they send off branches, whilst on the contrary, the branches of nerves are often larger than the trunk from which they, proceeded. It is no unfrequent occurrence for malformed, children to be born without a brain, yet, with a perfect nervous system." The most rational idea, therefore, we can entertain on the present subject, is, that the nerves are formed in the parts where we find them, and that they are connected to those parts of the organs from which we are accustomed to say they proceed. Nerves are vascular, and we can inject them with subtile injections...}. is of of , o " . . . . . . . . ; The nerves, then, proceeding from, or: being connected with the brain, medulla spinalis, and visceral nerve, may betraced, ramifying throughout the body in the mannet already mentioned, till they antive at the part for the supply of which they are designed. They then split into numerous branches which communicate with each other, and again subdivide and rejoin, their communications appearing to multiply as they become more minute; so that every part of the body has a kind of net work of nerves, which is minute in proportion to the susceptibility and sensibility it possesses. . . . . . . . . . . . . . . * * * * * • *. * ". o, , , This general and imperfect sketch of the anatomy of the nervous system, relates only to what may be discovered by our unassisted sight. If by means of the microscope we endeavour to observe the ultimate nervous fibres, persons in general are as much at a loss as when by the same means they attempt to trace the ultimate muscular fibres. “Those fibres which we can split off

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from a nervous packet, in the manner: before mentioned, though “too minute to admit of further subdivision, appear by the microscope to be themselves packets. of smaller threads. It is generally asserted by microscopical observers, that the nerves and medullary matter of the brainiand spinal marrow are the same, and are composed of very minute fibres. Fontana speaks confidently on this point; and he further says, that he has seen these nervous: fibres regenerated in the medium which has been formed to unite a divided; nerve. o. He describes the onervous fibres in every part of the nervous system as cylindrical, pursuing a slightly undulating course,” and being in a considerable degree transparent. He states also that they are larger than the ultimate fibres of muscles. -: , . . . . . . . - . . . . ... I

Microscopical observers also tell us, that

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