ELECTRIC FISH

Southland Times, Issue 19223, 19 April 1924, Page 9

ELECTRIC FISH

PISCATORIAL DYNAMOS. SOME UGLY CUSTOMERS. POWERFUL CURRENTS USED. Second only to the baffling mystery of what electricity is, which still puzzles the leading scientists of the world, are the marvellous and astonishing living batteries of certain fishes which have the magical power of producing their own electricity at will and in quantities large enough to make them dangerous customers to meet. > These animated “induction coils” in the shape of fishes inhabit various parts of the seven seas, and although scientists have studied them assiduously for years, their secrets are still hidden in the microscopic cells of their electrical organs. Foremost among,these piscatorial dynamos, which M. Van Demark writes about in “Practical Electrics,” is the electric eel of the brackish waters of South America. This eel is not unlike the common river eel familiar to everyone. It grows to the astonishing length of six and seven feet, but the average specimens of this species are about four feet long This eel is nothing more than a fish in an extended and elongated form, and possesses a powerful electric battery near the tail with which it stuns its prey and drives away its natural enemies. Few denizens of the deep, large or small, would relish a second encounter with an electric eel. When attacked it merely claps its “livewire” caudal (tail) appendage against its enemy anA presses the button. The victim instantly gets a powerful shock of electricity which is strong enough to knock a man down. LIVE HORSES AS BAIT! Scientists who have dissected these eels to discover “the reason” have been defied. They found that the electrical organs consist of two pairs of longitudinal organs located between the skin and the muscles of the caudal region, composed of 240 cells and supplied by more than 200 nerves. The eel can discharge current enough to kill an animal of considerable size and can easily knock down a man or horse. After a few consecutive shocks the battery is exhausted and the eel has to retire to a near-by mud-bank to rest, so that he can generate a new supply. In an hour or two he is ready for the next victim. This eel is very good to eat, but no one cares to take them off the hooks, so the common and horrible way to catch them is to drive horses into the bayous where they are known to be plentiful. The eels attack the horses and quickly exhaust their batteries. When they are powerless to do any further electrocution they are speared by the natives. Not infrequently horses are lost in this manner of fishing. THE TORPEDO RAY. The eel is not the only denizen of the deep to be safeguarded by powerful electric batteries. There is the torpedo ray, or skate, which looks like a three-corn-ered kite with a long tail, equally dangerous to handle without rubber gloves. There are also several quite unrelated fishes which possess the extraordinary property of communicating an electric shock ’to animals with which they come in contact.

In all cases the electric organs are like a mass of closely packed prisms, each divided series of compartments filled with a gelatinous substance. The electric ray has its batteries near the head. They are supplied with energy from large nerves proceeding from the brain. The ray is an ugly customer, and can give as much trouble as the electric eel. A man receiving a shock from a large ray will remember it for a long time, if, indeed, he is not killed outright. Even the little rays can give quite a shock when molested. The electric ray is a member of the skate family, and most skates can produce more or less electricity, but the ray is the only one of this species which is dangerous to handle. Then there is the electric cat-fish from the Nile, which carries about a powerful storage battery concealed under its skin next to the muscles. This battery is a layer or blanket of electric cells covering most of the body. The charge can be delivered at will, and is quite powerful, but, as the fish never attains large proportions, its shock is not dangerous to anything except small animals. FISH FROM THE DEPTHS.

While all the fish mentioned are capable of producing electricity for hunting and defensive purposes, not one of them utilises the current for electric lighting. And yet, strange as it may seem, there are plenty of other fishes which do use electricity produced by themselves for this very purpose. Not until the last eight or ten years ‘has any attempt been made to investigate the life of the deeper parts of the ocean. But the trawls and dragnets suspended a mile under the water, where it is necessarily total darkness all the time, reveal a multitude of small fishes each equipped with an electric light. Without this light they would, of course, be unable to see at all at this great depth, where the sunlight can never penetrate. The nets bring up a host of these small fishes, and in nearly every case they are equipped with the brightest eyes and little individual lanterns to light their way along the dark pathways of the deep.

No man knows just how the electricity for the light is produced.