eap in the
middle of the pack. The second and third times, you in like manner put
the heap in which he says it is, at bottom; the number each time being
three. Then looking at the pack with your glass, as if to discover
which the card was, you lay the cards down, one by one, and the
twentieth will be the card fixed on.

_The Card in the Ring._

Get a ring, made of any metal, in which is set a large transparent
stone or piece of glass, to the bottom of which is fastened a small
piece of black silk; under the silk is to be the figure of a small
card; and the silk must be so constructed that it may be either drawn
aside or spread, by turning the stone round.

You then cause a person to draw the same sort of card as that at the
bottom of the ring; and tell him to burn it in the candle. Now, the
ring being so constructed that the silk conceals the card underneath
it, you first show him the ring, that he may see it is not there, and
tell him you will make it appear; then rubbing the ashes of the card
on the ring, you manage to turn the stone or glass dexterously round,
and exhibit to him the small card at the bottom.

_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, and the glass must be wider than the distance
between the frame, by at least the width of a card. The glass in the
middle must be made to move in two grooves, and so much of the
quicksilver must be scraped off, as is equal to the size of a common
card. You then paste over the part where the quicksilver is rubbed
off, a piece of pasteboard, on which is a cord, that must exactly fit
the space, which must at first be placed behind the frame.

Fix this mirror against a partition, through which two strings are to
go, by which an assistant in an adjoining room can easily move the
glass in the grooves, and make the card appear or disappear at
pleasure. Or it may be done without an assistant, if a table be placed
against the partition, and a string from the glass be made to pass
through a leg of it, and communicate with a small trigger, which you
may easily push down with your foot, and at the same time wiping the
glass with your handkerchief, under the pretence that the card may
appear more conspicuous; which will also serve most effectually to
disguise the operation.

Having every thing thus arranged, you contrive to make a person draw
the same sort of card as that fixed to the mirror;