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All these different organic ganglia constitute together the sympathetic nerve system, organ of that part of the mind which directs the vital operations of the body in apparent independence of the intelligence commonly called "the mind," an intelligence which acts through the cerebro-spinal system. Yet this independence is far from being absolute.
It consists of small masses of gray and white nervous matter, that seem to be small brains with nerves running from them. These are called ganglia, and are arranged on each side of the spine, while small nerves from the spinal marrow run into them, thus uniting the sympathetic system with the nerves of the spine.
These heavy-eyed men with the alcoholized brains, these pallid youths with the nicotized optic ganglia and thinking-marrows brown as their own meerschaums, of whom you meet too many, will ask all your wisdom to deal with their poisoned nerves and their enfeebled wills. Nearly seventeen hundred children under five years of age died last year in this city.
The ganglia contain the cell-bodies which serve as nutritive centers; and, in the case of the sympathetic ganglia, these cell-bodies are the places where the fiber terminations of one neuron connect with, and stimulate, other neurons.
Under the microscope, it is seen to be formed by the close juxtaposition, the welding, end to end, of the ganglia, which can be distinguished one from the other by a slight intermediate groove. The bulkiest are the first, the fourth and the tenth, or last; these are all very nearly of equal size. The rest are barely half or even a third as large as those mentioned.
Nor has it been proved that the nervous influence is affected in such a way as directly to impair the innervation of the organic functions, which derive their chief impulse to action from the scattered ganglia of the sympathetic system.
The ganglia of each segment exercise immediate supervision over the structures of their respective territory, while they pass on impulses to other ganglia so that movements involving many segments can be properly adjusted. Everything an earthworm does is controlled by the cells grouped in these ganglia, or scattered along the intervening connecting cords.
This sympathetic system of ganglia and nerves, by-the-bye, had long been a puzzle to the physiologists.
The murderess chooses the under part of the chin as the point attacked in order to strike the principal nerve-centres, the cephalic ganglia, and thus to do away with life at one blow. When this vital seat is poisoned by the toxin, death is instantaneous.
He was one who saw nothing, knew nothing, sought nothing but the making and buying of that which sells; who out from the magic of his hand rolled over miles of iron road, ton upon ton of food and metal and wood, of coal and oil and lumber, until the thronging of knotted ways in East and real St. Louis was like the red, festering ganglia of some mighty heart.
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