First place a knife straight before you, then two others which you place, blade upon blade, over the first. Finally, the two last ones are arranged transversely, their blades passing over those of the two knives put down in the second instance, and below the blade of the first knife. By taking hold of the handle of the first knife, you can lift them up all at once without breaking the equilibrium. The Tack in the Ceiling. To nail a tack in the ceiling without hammer, using a ladder or chair to reach it, seems as impossible as pulling the moon down from the sky. Yet, with a little cleverness, it is quite an easy thing to do. Place a tack, head downwards, on a half dollar, then place a small piece of tissue paper over it, so that the point of the tack passes through. [Illustration] Then turn the sides of the paper down round the coin. Throw the whole, point upwards, violently against the ceiling, trying to keep this projectile of a new description from turning over on its course. With a little practice the knack is soon acquired. The tack enters the ceiling, the violence of the shock tears the paper, which, carried away by the coin, falls to the ground. Suppose you have a light object to suspend on the ceiling; you may do it in this manner without much trouble. Simply tie a thread to the tack, the object being attached to the other end. If the projectile is well thrown the tack will go right in, and stick very firmly. The Jumping Pea. Take an unbroken straw, four or five inches long, not closed by knots, but forming a tube, and about one twentieth of an inch in diameter. Divide one of its extremities to a length of about half an inch in four, five or six parts, which separate slightly, so as to form a truncated cone. After having thus prepared the straw, take a dry pea, with a larger diameter than that of the tube, and place it in the cone. Hold the tube upwards, and blow into it at the opposite end. [Illustration] The pea will be forced upward by the air column which you blow into the tube. It will remain suspended in the air as long as the interior pressure continues, then fall back into the arms of the cone. To vary that experiment pass a long pin through the pea, the point of which is turned into the tube. When well thrown up, the pea can be maintained at a distance of two or three inches from the mouth of the straw. According to the stronger or weaker blast of breath, the pea will go up or down. To Acquire a True Eye. Here is a peculiar and clever recreation, easily performed, though at first sight it may appear difficult. Put a tumbler upside down. By means of bread crumbs, fix a match vertically on the top. On the edge of the table place another match, partly raised on a piece of cork or wood. Stoop down and aim at the vertical match on the glass, so that the one on the table is in the exact line of fire.