Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

ciplcs, (the others, perhaps, not being quite normal,) and, per- haps, contaminated by the presence of some foreign noxious principle, tends to the production of the epileptic state. Experimental physiology supplies us with very striking facts, to show that simply an insufficient supply of blood to the brain is very apt to occasion epileptic convulsions. Every one who has witnessed the slaughter of sheep, which is effected by dividing the great arteries in the neck, must have observed the strong convulsions which so frequently precede death in animals killed in this way. All animals killed by loss of blood exhibit the same phenomena precisely, and die with convulsions of a more or less violent kind. Such facts suggest the rationale of treat- ment for cure, which can be done, in some degree at least, by electric currents. If we follow the views of Dr. Marshall Hall, we find that the diseases of the spinal system exist under several forms, which admit generally of being reproduced in experiments for the purpose; and one great advantage in the study of experimental research in the spinal system, is, that there are thus frequently presented the " types " of its dis- eases. " In general," he says, " the diseases of the spinal system occur under the form of spasm, of paralysis, or of the two combined, viz., spasmo-paralysis. They are all primarily affections of the excito-motor muscular system, to the exclusion of the sentient or cerebral system — a singular confirmation of a physiological doctrine, that these two systems are totally distinct from each other. " Generally, spasm consists in irritation of nervous tissue, still retaining its normal structure ; whilst paralysis implies a lesion of that structure. But the structure of the nervous tissue must be viewed under several aspects; thus this tissue may be injured by being lacerated or bruised at any given point; but it may be strangely injured in a given point, by injury inflicted at a distance, through the means of shock. In this manner spasm is apt to lead to paralysis, and for the obvious reason that this peculiar lesion is of the most intimate or atomic character, un- like the division or separation of its atoms by laceration, &c.;