Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.
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parts receive no impulse at all from that centre, whether mental
or physical; and although those parts may still be perfectly
healthy in themselves, yet are they thus incapable of taking part
in voluntary acts. (See p. 242 and Notes on p. 477.)
" Furthermore, whatever interferes materially with the conduct-
ing power of nerve-fibre, or the generating power of nerve ves-
cicle, (gray matter,) will constitute a paralyzing lesion. In the
first place, poisoning of the nervous matter will operate in this
way : For instance, soak a portion of the nerve of a living ani-
mal in chloroform, or ether, or opium, and that nerve will fail to
propagate the normal nervous force as long as the influence of
the poison lasts. In a similar way, the poison of lead in the
human system may paralyze, either by weakening the conduct-
ing or the generating power of the nervous matter. Poisons
formed in the living system may operate in the same way; such
as retained urinary or biliary principles, or the poisons of rheu-
matism, gout, &c.
" Secondly, any morbid process which greatly impairs the natu-
ral structure of nerve matter will paralyze. Thus inflamma-
tion will do this ; so also will atrophy, or wasting from want of
sufficient supplies of nutrient matter, as where the flow of
blood is lessened, or cut off. The opposite conditions of harden-
ing, and so of red or white softening, of the nervous matter be-
come paralyzing lesions from the same reason, viz., that they
greatly impair or destroy the nerve structure.
" Thirdly, a solution of continuity of nerve fibre will paralyze.
Cut a nerve across, and you have immediate palsy of the parts
which the nerve supplies below the section. This solution of
continuity from a final melting down of the fibres is, I have no
doubt, the more frequent cause of sudden paralysis in cases of
softening, or in cases of sanguineous effusion.
" Fourthly, pressure on a nerve or nervous centre will paralyze.
Of this we have many proofs as regards nerves. A nerve, as for
instance, included by a ligature, or compressed by a tumor, is
paralyzed thereby. A fracture of the skull, with depressed bone,
will paralyze, if the brain is sufficiently compressed. An apo-
plectic clot on the exterior of the brain paralyzes by compression;
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