. Half hours with fishes, reptiles, and birds . werful shocks can be given to a num-ber of people. When the powers of the fish were firstdiscovered it was publicly used as a cure for many dis-eases and hundreds of persons received the shocks. The upper surface ofthe battery is posi-tive, the lowernegative. In all about fif-teen different vari-eties of electric raysare known, and theyare sometimes thecause of the tem-porary disablement of fishermen. By its batteries the rayis able to benumb and even kill its prey. The batteries arealso used in defense, as the moment a shark attempts toseize one
. Half hours with fishes, reptiles, and birds . werful shocks can be given to a num-ber of people. When the powers of the fish were firstdiscovered it was publicly used as a cure for many dis-eases and hundreds of persons received the shocks. The upper surface ofthe battery is posi-tive, the lowernegative. In all about fif-teen different vari-eties of electric raysare known, and theyare sometimes thecause of the tem-porary disablement of fishermen. By its batteries the rayis able to benumb and even kill its prey. The batteries arealso used in defense, as the moment a shark attempts toseize one of these rays, it receives a stunning shock. TheGymnotus or electric eel of South America (Fig. 42) isprovided with an electric armament even more batteries are two pairs of organs just below the skin :one pair back of the tail, and the other near the anal cells are very small, as many as two hundred and fortybeing found in a square inch of surface. In the lakes andstreams where they abound these eels have been caught at. Fig. 42. —The Electric Eel. WEAPONS OF FISHES 71 times by driving wild horses into the pools. The rushingand stamping of the horses cause the eels to resent theattack with such powerful shocks that they are soon ex-hausted and can be handled. Some of the eels are sixfeet in length, and the slightest attack by an enemy issufficient to bring out this wonderful muscular action whichtakes the form of a violent electric shock. When white people first visited tropical Africa, theyfound that some of the natives used a singular test to dis-cover the guilt of suspected persons. The accused party
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1906
