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winter, but appear in spring, and bite readily at the hook, which common eels in that neighbourhood will not. They have a larger head, a blunter nose, thicker skin, and less fat than the common sort; neither are they so much esteemed, nor do they often exceed three or four pounds in weight.

Common eels grow to a large size, sometimes so great as to weigh fifteen or twenty pounds, but that is extremely rare. As to instances brought by Dale and others, of these fish increasing to a superior magnitude, we have much reason to suspect them to have been congers, since the enormous fish they describe have all been taken at the mouths of the Thames or Medway.

The eel is the most universal of fish, yet it is scarce ever found in the Danube, though it is very common in the lakes and rivers of Upper Austria.

The Romans held this fish very cheap, probably from its likeness to a snake.

Vos anguilla manet longæ cognata colubræ,
Vernula riparam pinguis torrente cloaca.

For

JUVENAL, Sat. v.

you is kept a sink-fed snake-like eel.

On the contrary, the luxurious Sybarites were so fond of these fish, as to exempt from every kind of tribute the persons who sold them.

SECTION II.

[Pennant.

Sword-Fish.

Xiphias Gladius.-LINN.

THIS is a native of the Mediterranean, and is mostly found in the Sicilian sea; grows to a very large size, sometimes measuring twenty feet in length; and is of an active and predacious disposition, feeding on the smaller kind of fishes, which it kills by pierc. ing with its sword-shaped snout. The body is long, round, and gradually tapers towards the tail: the head fattish, the mouth

wide, both jaws ending in a point, but the upper stretched to a great distance beyond the lower: this part, which is commonly called the sword, is flattish above and beneath, and sharp on the sides: it is of a bony substance, covered by a strong skin or epidermis: down the middle of the upper part runs an impressed line or furrow, and three similar ones on the lower surface: the tongue is free, or unconnected with the palate, and is of a strong texture, and in the throat are certain rough bones: the nostrils are double, and seated near the eyes, which are moderately large and protu. berant: the body is covered by a thin skin, having a thick fatty membrane lying beneath; the lateral line is placed near the back, and is formed of a series of longish black specks: the dorsal fin is very high at its commencement, and sinking suddenly, becomes very shallow, and is continued to within a small distance from the tail, terminating in an elevated process: the vent-fin is placed nearly opposite this part beneath, and is moderately small, and much wider at each extremity than at its middle: the pectoral fins are rather small, and of a lanceolate shape: the tail is large and crescent-shaped; and on each side the body, immediately before the tail, is a strong finny prominence or appendage. The general colour of the sword-fish is brown, accompanied by a deep steelblue cast on the head and upper parts, and silvery white on the sides and abdomen.

Mr. Pennant observes, that the ancient method of taking the sword-fish, particularly described by Strabo, agrees exactly with that practised by the moderns at the present day. A man ascends one of the cliffs that overhang the sea, and as soon as he spies the fish gives notice, either by his voice or by signs, of the course it takes. Another person, stationed in a boat, climbs up the mast, and, on seeing the fish, directs the rowers to it. As soon as he thinks they are got within reach, he descends, and taking a spear in his hand, strikes it into the fish; which, after wearying itself with its agitations, is seized and drawn into the boat. It is much esteemed by the Sicilians, who cut it in pieces and salt it: this process was anciently performed, particularly at the town of Thurii, in the bay of Tarentum; and hence the fish was called Tomus Thurianus *.

* Plin. l. 32, c. 11.

The sword-fish is occasionally found not only in the Mediter ranean but in the Northern seas, and sometimes in the Pacific: it is probable, however, that it has been often confounded with a different species more common in that ocean.

This fish is bold and active, and in one instance was known to attack an East Indiaman, which he would certainly have sunk, by driving his long serrated snout or sword through its hulk, but that he killed himself by the violence of his attack; in consequence of which the sword remained in the timbers of the ship, and no leak of any consequence ensued. A piece of the hulk, with a part of the fish's sword imbedded in it, was presented to the British Museum, and may still be seen there as an object of curiosity. [Pennant. Shaw. Editor.

SECTION III.

Electrical Eel, or Gymnote.

Gymnotus electricus.-LINN.

Electrical Torpedo, or Ray.

Raia torpedo.-LINN.

THERE are various fishes which have a power of collecting and discharging small portions of the electric fluid; some a quantity so minute as to be scarcely sensible, like that thrown forth from the hair of the cats' back, to the hand that touches it: but others in a quantity so considerable, as to produce exhaustion and numb. ness of the nerves exposed to its action, or even a shock equal to that of a large Leyden phial.

Of this last kind the two most celebrated are those which we have enumerated at the head of the section; and which, though in the artificial system of Linnæus, belonging to different orders, we shall here contemplate simultaneously.

The TORPEDO has been celebrated both by ancients and moderns for its wonderful faculty of causing a sudden numbness, or painful sensation, in the limbs of those who touch or handle it. This power the ancients, unacquainted with the theory of electricity,

were contented to admire, without attempting to explain; and, as is usual in similar cases, magnified it into an effect little short of what is commonly ascribed to enchantment. Thus we are told by Oppian, that the torpedo, conscious of his latent faculty, when caught by a hook, exerts it in such a manner, that passing along the line and rod, it benumbs the astonished fisherman, and sud, denly reduces him to a state of helpless stupefaction.

« Ναι μεν κι ναρκη,” &c.

The hook'd torpedo, with instinctive force,
Calls all his magic from its secret source;
Quick thro' the slender line and polish'd wand
It darts; and tingles in th' offending hand*.
The palsied fisherman, in dumb surprise,
Feels thro' his frame the chilling vapours rise:
Drops the lost rod, and seems, in stiffening pain,
Some frost-fix'd wanderer on the polar plain.

It is affirmed by Pliny, that the torpedo, even when touched with a spear, or stick, can benumb the strongest arm, and stop the swiftest foot.

It is well observed, by Dr. Bloch, that these exaggerations on the part of the ancients are the less to be wondered at, when we reflect on similar ones in modern times. Thus, when Muschen. broek happened accidentally to discover and feel the effect of the electric shock, from what is called the Leyden phial, he represented it of so terrible a nature as to affect his health for several days afterwards; and declared that he would not undergo a second for the whole kingdom of France. Yet this is now the common amusement of philosophical curiosity.

The observations of the learned Redi and others, in the seventeenth century, had tended, in some degree, to elucidate the peculiar actions and anatomy of the torpedo; but it was reserved for more modern times, and for our own ingenious countrymen in particular, to explain, in a more satisfactory manner, the particu. lars of its history; and to prove that its power is truly electric.

* There are not wanting some who insist that this is no exaggeration, and that the electricity of the torpedo is really conducted in this manner.

The first experiments of this kind were made by Mr. Walsh, of the Royal Society of London, at Rochelle, in France, in the year

1772.

"The effect of the torpedo," says Mr. Walsh," appears to be absolutely electrical, forming its circuit through the same conduc tors with electricity, and being intercepted by the same non-conductors, as glass and sealing-wax. The back and the breast of the animal appear to be in different states of electricity; I mean, in particular, the upper and lower surfaces of the two assemblages of pliant cylinders engraved in the work of Lorenzini*. By the knowledge of this circumstance, we have been able to direct his shocks, though they were small, through a circuit of four persons, all feeling them; and likewise through a considerable length of wire held by two insulated persons, one touching his lower sur. face, and the other his upper. When the wire was exchanged for glass or sealing-wax, no effect could be obtained: but as soon as it was resumed, the two persons became liable to the shock. These experiments have been varied many ways, and repeated, times without number, and they all determined the choice of conductors to be the same in the torpedo as in the Leyden phial. The sensations, likewise, occasioned by the one and the other, in the human frame, are precisely similar. Not only the shock, but the numb. ing sensation, which the animal sometimes dispenses, expressed in French by the words engourdissement and fourmillement, may be exactly imitated with the phial, by means of Lane's electrome. ter the regulating rod of which, to produce the latter effect, must be brought almost into contact with the prime conductor which joins the phial. It is a singularity that the torpedo, when insulated, should be able to give us, insulated likewise, forty or fifty successive shocks, from nearly the same part; and these, with little, if any, diminution of their force. Each effort of the animal, to give the shock, is conveniently accompanied by a de pression of the eyes, by which even his attempts to give it to non. conductors can be observed in respect to the rest of his body, he is in a great degree motionless, though not entirely so. I have taken no less than fifty of the above mentioned successive shocks, from an insulated torpedo, in the space of a minute and a half.

* Observazioni intorno alle torpedini. 1769.

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