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part of a minute, it gave him so great pain but upon taking the hand away, the numbness went off, and all was well again. This numbing qua

lity continued in this torpedo even after it was "dead; and the very skin was still possessed of its "extraordinary power till it became dry." Condamine informs us of a fish possessed of the powers of the torpedo, of a shape very different from the former, and every way resembling a lamprey. This animal, if touched by the hand, or even with a stick, instantly benumbs the hand and arm to the very shoulder; and sometimes the man falls down under the blow. These animals, therefore, must affect the nervous system in a different manner from the former, both with respect to the manner and the intention; but how this effect is wrought, we must be content to dismiss in obscurity.

[From a series of experiments made by Mr. Walsh, and communicated to the Royal Society, it appears that the powers of this animal are purely electric; though no spark could ever be discovered to proceed from it, nor were pith-balls ever affected by it." A live Torpedo," says this ingenious experimentalist," was placed on a table; round another table stood five persons insulated; two brass wires, each thirteen feet long, were suspended from the ceiling by silken strings; one of these wires rested by one end on the wet napkin on which the fish lay; the other end was immersed in a basin full of water placed on a second table, on which stood four other basins likewise full of water: the first person put a finger of one hand in the basin in which the wire was immersed, and a finger of the other hand in a second basin: the second person

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put a finger of one hand in this last basin, and a finger of the other hand in the third; and so on successively, till the five persons communicated with one another by the water in the basins. In the last basin, one end of the second wire was immersed, and with the other end Mr. Walsh touched the torpedo; when five persons felt a commotion, which differed in nothing from that of the Leyden experiment, except in the degree of force. Mr. Walsh, who was not in the circle of conduction, received no shock. This experiment was repeated several times, even with eight persons, and always with the same success. The action of the torpedo is communicated by the same mediums as that of the electric fluid. The bodies which intercept the action of the one, intercept likewise the action of the other. The effects produced by the torpedo resemble in every respect a weak electricity. This exhibition of the electric powers of the torpedo, before the Academy of La Rochelle, was at a meeting held for the purpose, in my apartment, on the 22d of July, 1772, and stands registered in the Journals of the Academy.

"The effect produced by the torpedo, when in air, appeared, on many repeated experiments, to be about four times as strong as when in water. The numbness produced by the shock of the torpedo was imitated by artificial electricity, and shown to be producible by a quick concussion of minute shocks. This, in the torpedo, may be effected by the successive discharges of his numerous cylinders, the organs of its power, in the nature of a running fire of musquetry; the strong single shock may be his general volley. In the continued effect, as well

as the instantaneous, his eyes, which are usually prominent, are, withdrawn into their sockets. A coated vial was applied to it, but could not be charged."

The organs of this electric matter are placed on each side of the cranium and gills, reaching from thence to the semi-circular cartilage of each fin, and dispersed over the whole space between the skin of the upper and of the under surface of the fish: they are thickest at the centre, and become gradually thinner towards the extremities. Each organ consists wholly of perpendicular columns, reaching from the upper to the under surface of the body, varying in length, according to the thickness of the parts of the body where they are placed. The columns are attached to each other by strong inelastic fibres, passing directly from one to the other.

Two other fishes are known to possess this extraordinary power: the electrical Eel, which is able to give a shock even greater than the torpedo; and the electric Silurus, whose shock is much less vigorous than either of the others.]

CHAP. IV.

Of the Lamprey, and its Affinities.

THERE is a species of the Lamprey served up as a great delicacy among the modern Romans, very different from ours. Whether theirs be the maræna of the ancients, I will not pretend to say; but there is nothing more certain than that our lam

prey is not. The Roman lamprey agrees with the ancient fish in being kept in ponds, and considered by the luxurious as a very great delicacy.*

The Lamprey known among us is differently estimated, according to the season in which it is caught, or the place where it has been fed. Those that leave the sea to deposit their spawn in fresh waters are the best; those that are entirely bred in our rivers, and that have never been at sea, are considered as much inferior to the former. Those that are taken in the months of March, April, or May, just upon their leaving the sea, are reckoned very good; those that are caught after they have cast their spawn, are found to be flabby and of little value. Those caught in several of the rivers in Ireland the people will not venture to touch; those of the English Severn are considered as the most delicate of all other fish whatever.

The lamprey much resembles an eel in its general appearance, but is of a lighter colour, and rather a clumsier make. It differs however in the mouth, which is round, and placed rather obliquely below the end of the nose. It more resembles the mouth of a leech than an eel; and the animal has a hole on the top of the head through which it spouts water, as in the cetaceous kind. There are seven holes on each side for respiration; and the fins are formed rather by a lengthening out of the

[* * The fish considered by the Romans as one of their chief delicacies, was the Roman Maræna: it is of the size and appearance of an eel, but has no pectoral fins, and only a single breathing-hole on each side of the neck. It is a native of the Mediterranean seas, and of a dark greenish brown, thickly variegated with dull yellow irregular marks.]

skin, than any set of bones or spines for that purpose. As the mouth is formed resembling that of a leech, so it has a property resembling that animal of sticking close to and sucking any body it is applied to. It is extraordinary the power they have of adhering to stones; which they do so firmly as not to be drawn off without some difficulty. We are told of one that weighed but three pounds; and yet it stuck so firmly to a stone of twelve pounds, that it remained suspended at its mouth, from which it was separated with no small difficulty. This amazing power of suction is supposed to arise from the animal's exhausting the air within its body by the hole over the nose, while the mouth is closely fixed to the object, and permits no air to enter. It would be easy to determine the weight this animal is thus able to sustain; which will be equal to the weight of a column of air of equal diameter with the fish's mouth.

From some peculiarity of formation, this animal swims generally with its body as near as possible to the surface; and it might easily be drowned by being kept by force for any time under water. Muralto has given us the anatomy of this animal; but, in a very minute description, makes no mention of lungs. Yet I am very apt to suspect, that two red glands tissued with nerves, which he describes as lying towards the back of the head, are no other than the lungs of this animal. The absolute necessity it is under of breathing in the air, convinces me that it must have lungs, though I do not know of any anatomist that has described them.

The adhesive quality in the lamprey may be in some measure increased by that slimy substance

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