THE CARD IN THE MIRROR.
Provide a mirror, either round or oval, the frame of which must be at least as wide as a card. The glass in the middle must be made to move in the two grooves, and so much of the quicksilver must be scraped off as is equal to the size of a common card. You will observe that the glass must likewise be wider than the distance between the frame by at least the width of a card.
Then paste over the part where the quicksilver is rubbed off, a piece of pasteboard, on which is a card, exactly fitting the space, which must at first be placed behind the frame.
This mirror must be placed against a partition, through which is to go two strings, by which an assistant in the adjoining room can easily move the glass in the grooves, and consequently make the card appear or disappear at pleasure.
Without an Assistant.—Place a table against the partition, and let the string from the glass pass through a hollow leg of it, and communicate with a small trigger, which you may easily push down with your foot, and at the same time be wiping the glass with your handkerchief, that the card may appear the more conspicuous. It may also be diversified by having the figure of a head, say of some absent friend, in the place of the card.
Matters being thus prepared, you contrive to make a person draw the same sort of card with that fixed to the mirror, and place it in the middle of the pack: you then make the pass, and bring it to the bottom; you then direct the person to look for his card in the mirror, when the confederate behind the partition is to draw it slowly forward, and it will appear as if placed between the glass and the quicksilver. While the glass is coming forward you slide off the card from the bottom of the pack, and juggle it away.
The card fixed to the mirror may easily be changed each time the experiment is performed. This trick may be also made with a print that has a glass before it, and a frame of sufficient width, by making a slit in the frame through which the card is to pass; but the effect will not be so striking as in the mirror.