_The Nature and Power of Will._--The power of effecting, voluntarily, the transfer of electric matter from one part of the interior of the body to a different, seems to belong, in some necessary degree, to all bodies possessed of life. The object is to make space for medium of space to enter, and by its pressure to put the animal in a state of locomotion. The snake, worm, and snail do so to be pressed onward along the ground; the oyster, to have the shells firmly collapsed; the limpit, to be pressed against the rock; and each, cerebrally wills the replacement of electric matter to displace the cause of pressure, medium of space, for the grovelling reptile to be at rest--the oyster, that the shells may be opened; the limpit, when willing to fall into the water. The fly, lizard, and walrus, so de-electrise the body, as to reverse the direction of what is supposed to be their natural weight, by which means each becomes pressed upwards, and walks with the back downwards--which, to be consistent with the established philosophy, should be considered _repellent gravitation_. The goat voluntarily de-electrises his body to have it pressed with double force against the slippery rock; the lynx, to have mesmeric long vision; the cat, to have opaque vision, or "see through the dark;" the fire-fly, to effect reduction of the optic pressure productive of sensations of colour. The carrier-pigeon effects self de-electrisation to the clairvoyant degree, by which the external object, the turret at Constantinople, promotes the sensation which indicates at once the shortest direction of flight from London to the birth-place of the bird. The eagle de-electrises itself inwardly, the same as if by the mesmeric passes, to promote olfactory lucidity, by which to ascertain the presence of carrion on the ground. Fishes effect internal de-electrisation, somehow by means of the contents of the swim, for influent medium of space to propel the body with a velocity superior to the power of the short, flexible fins. The flight of birds is not effected by wing motion, or wing powers. The crow, eagle, and kite sail in all directions on extended motionless wing, and the odd wing-flap now and then given, is only to assist in keeping the body in the necessary electric condition. The swallow is darted most rapidly through the air with closed wing, and changes acutely, without way, the direction of flight, by changing instantaneously the direction of impulse. With the greatest wing-agitation the hawk remains at times stationary in the air. The fish, bird, and bullet are impelled by the same cause, pressure, by the medium of space on the de-electrised rear.