We propose to keep a coin horizontally in equilibrium on the rim of a tumbler, and it must rest on the glass only by its extreme edge, as shown by the figure which gives the complete demonstration. [Illustration] Take a silver dollar and place it between the prongs of two forks covering each other, then place the edge of the coin upon the glass and draw the handles of the forks together, or distend them till the whole are balanced. The center of gravity will then be at the point of contact, and you may give a slight swing without the risk of breaking the equilibrium thus obtained. The Submerged Coin. In order to make the previous experiment more significant, you may present it also in the following manner: In a soup plate place a coin; beside the latter an inverted glass, then pour water into the plate just to cover the coin. You then inform the spectators that you will withdraw the coin from the plate without wetting your fingers. You will meet with a great deal of disbelief from many of your friends looking on. Leave them in doubt as to the success of your operation. Cut a round piece off a cork, on the top of which place some pieces of paper and matches, push the whole underneath the glass, light the matches and wait. As soon as the combustion is over, you will see the water leave the plate and enter the glass, wherein it rises, leaving the piece absolutely dry at the bottom of the plate. You can then execute what you offered at first--take out the coin without wetting your fingers. [Illustration] As a variation of the preceding experiment, obtain a flat-bottomed tumbler or glass goblet (but the bottom must be flat), a pocket handkerchief and a coin. These are to be seen by everybody present. Procure a watch glass, or a round piece of glass like an eye-glass. This is not to be shown. Now show to the bystanders that you place the coin (say a fifty-cent piece, for example) in the middle of the handkerchief, and, throwing back two sides of the latter, point out again that the coin is still in its place. To show that there is no deception ask someone to hold the coin in the handkerchief. Then place underneath it a glass containing a little water and call out, “Hey, Presto! Fly!” The person lets go of the coin and the noise of its falling to the bottom of the glass is plainly heard. You take up the handkerchief, and every one is astonished at the disappearance of the coin, which you can produce from another person’s hat. Really the trick is very simple. For the coin supposed to be held in the handkerchief you must dexterously substitute the watch glass or eye glass. The person holding it, of course, declares he has the coin fast. When he drops the eye glass it makes the same noise against the tumbler as would the coin, though, of course, it cannot be seen in the water. It is a capital trick if smoothly performed. The Smoke Rings.