“The _Gymnotus_ can stun and kill fish which are in very various positions to its own body; but on one day, when I saw it eat, its action seemed to me to be peculiar. A live fish, about five inches in length, caught not half a minute before, was dropped into the tub. The _Gymnotus_ instantly turned round in such a manner as to form a coil, inclosing the fish, the latter representing a diameter across it; a shock passed, and there, in an instant, was the fish struck motionless, as if by lightning, in the midst of the waters, its side floating to the light. The _Gymnotus_ made a turn or two to look for its prey, which, having found, he bolted, and then went about searching for more. A second smaller fish was given him, which being hurt in the conveyance, showed but little signs of life, and this he swallowed at once, apparently without shocking it. The coiling of the _Gymnotus_ round its prey had, in this case, every appearance of being intentional on its part, to increase the force of the shock, and the action is evidently well suited for that purpose, being in full accordance with the well-known laws of the discharge of currents in masses of conducting matter; and though the fish may not always put this artifice in practice, it is very probable he is aware of its advantages, and may resort to it in cases of need.”[150] Animal electricity has been proved to be of the same character as that derived from other sources. The shock and the spark are like those of the machine; and the current from the animal, circulating around soft iron, like galvanic electricity, has the property of rendering it magnetic. It is important that we should now review these conditions of electrical force in connexion with the great physical phenomena of nature. It is sufficiently evident, from the results which have been examined, that all matter, whatever may be its form or condition, is for ever under the operation of the physical forces, in a state of disturbance. From the centre to the surface all is in an active condition: a state of mutation prevails with every created thing; and science clearly shows that influences are constantly in action which prevent the possibility of absolute repose.