A simple and convincing mode of proving the assertion. It has puzzled the heads of a good many people to known how the earth turns round. A German educational journal published in Frankfort gives the following directions for proving that the earth "does move:" Take a good-sized bowl, fill it nearly full of water and put it upon the floor of a room which is not exposed to shaking or jarring from the street. Sprinkle over the surface of the water a coating of lycopodium powder, a white substance sometimes used for the purposes of the toilet and which can be obtained at almost any apothecary's. Then upon the surface of this coating of powder make with powdered charcoal a straight black line, say an inch or two in length. Having made this black mark with the charcoal powder on the surface of the contents of the bowl, lay down upon the floor close to the bowl a stick or some other straight object so that it will be exactly parallel with the mark. If the line happens to be parallel with a crack in the floor or with any stationary object in the room this will serve as well. Leave the bowl undisturbed for a few hours and then observe the position of the black mark with reference to the object that it was parallel with. It will be found to have moved about, and to have moved from east to west - that is to say in the direction opposite to that of the movement of the earth on its axis. The earth, in simply revolving, has carried the water and everything else in the bowl around with it, but the powder on the surface has been left behind a little. The line will always be found to have moved from east to west, which is perfectly good proof that everything else has moved the other way.