The motion of a cyclone or tornado is in accordance with the same law that governs the motion of planets around the sun. It can be illustrated in a very simple manner by the spinning of a top. Spin a top on a perfectly smooth and level surface. It will be better if the peg of the top be blunt or round, so that there will be no tendency to settle steadily into some possible hole or depression. Now, the instant any degree of steadiness is attained, the top begins to move in small curves. If it be spun on a marble slab smoothly coated with fine flour or sand, it can be made to record its motions, which may then be carefully studied. It will be found that the form of the curve is nearly the same with every start. It will describe a parabola, pause a moment, then describe a second, and so on. The chief peculiarity of this separate curvilinear motion is that its direction is always in an _opposite_ direction to that of the rotation of the top. If the top turn from left to right, it will move from right to left, and vice versa. The same tendency will manifest itself even if the peg of the top be placed in a slight depression or socket, so that the curve cannot be made. Then the upper portion of the top will incline to one side, and begin describing a curve: but, as before, in a direction contrary to the direction of rotation. The common toy known as a gyroscope illustrates the last peculiarity also. It consists of a wheel within a metal frame, which has a peg like a top. If the wheel be made to revolve rapidly, the whole may be balanced on the peg: when the frame will begin to slowly revolve in the opposite direction: and if placed upon a smooth level surface, like the top it will tend to describe the same course. Still other illustrations of this principle are even more familiar than the spinning of a top. Any one who has seen the game of soldiers in a bowling alley knows that in order to make the ball turn to the left as it moves forward, it must spin the other way; that is, with the hands of a watch. To travel or curve to the right, it must spin in the contrary direction. So in our “great national game,” base-ball, the pitcher curves the ball any way he pleases merely by following this law. It is not necessary to take into account, as many do, the return trades, as occasioning the travel of a whirling storm; and the fact is, that the cyclone frequently travels more rapidly than the ordinary wind moving in the same direction. Now, the motion of the planets is similar: rotating in one direction, they travel in the other. So we find the general law is,