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

space, presenting six sides to each column or pile, much as is seen in the wax comb of the honey bee. Then each of these perpendicular tubes is minutely subdivided horizontally, by membranous diaphragms, into thin cells, which are filled with a kind of mucous secretion; and these again are traversed by a fringe of nerve filaments that come from the great eighth pair of nerves. According to Dr. Hunter, the torpedo has at each side, on an average, four hundred and seventy hexagonal tubes, averaging one and a half inches long each, — making in all nine hundred and forty piles. Each of these, he says, has a surface of two thousand diaphragms, and between the minute spaces of these exceedingly thin and simple membranes, there is a liquid, as we have just remarked, of an albuminous nature, (nine tenths water, a trace of salt, and one tenth albumen.) These all are animated by four large bundles of nerves, which arise in the brain, and are distributed throughout all the electric apparatus by multitudinous ramifications, until they are lost in the minute substance of all the diaphragms, but terminating exactly alike upon the same side of each diaphragm. But the electric organs, in all these fishes, are not exactly alike in arrangement, but are similar as they are in structure. Alexander von Humboldt has given a most graphic description of the gymnotus, or American electric eel, — also called the Suri- nam eel, because there found most plentifully. He relates that these fishes may kill a horse or mule at a blow ; and, conse- quently, a long time ago, it was found necessary to change the trail from Uritucu, through the steppes in South America, be- cause these great electric eels had accumulated in a stream on the former route that had to be forded. He says, that year after year, a great number of horses were benumbed, while crossing the stream, by these fishes, and were thus lost by being finally drowned in this passage. "We have just seen that in the flat fish torpedo, there were nine hundred and forty piles of two thou- sand series each ; but in the electric eel the tubes or piles do not stand perpendicularly, but are laid horizontally from head to tail, longer and less in number. This is, therefore, the most power- ful electric fish known; just as we might expect judging from 16*