_Explanation._--After the performer has borrowed the half-dollar, in the act of handing it to the gentleman for examination he adroitly changes it for one of his own, bearing the mark of a cross, which mark, is, of course, taken for that of the owner of the coin. The performer now asks for a programme, and while it is being procured he drops the actual borrowed coin into the smallest of the three envelopes, which are placed one inside the other and concealed by a book or some other object on the table. To facilitate the introduction of the coin, a tin tube, with a rather wide mouth, just large enough for the coin to pass through, is placed in the smallest envelope. After this coin has been introduced this tube is withdrawn, left in its concealed position, and the envelopes closed. The flaps of the envelopes are sealed with wax beforehand and prepared with the best gum arabic, which is allowed to dry. They are moistened with the tongue just before the performance of the trick, and, if cut as in Fig. 7, can all be closed at once while lying on the table. This packet is laid on the table under cover of the half of a programme used in the second stage of the trick. [Illustration: Fig. 7] To begin, the performer palms a similar packet of envelopes containing another half-dollar marked in exactly the same way as the one he handed to the gentleman, and it is hardly necessary to say, having the same appearance and bearing the same date. When rolling up the programme the performer retains it and hands the gentleman the packet of envelopes; and when going to his table for the wax leaves half of the programme and the half-dollar thereon. By the time the first coin is taken from the envelopes the packet containing the actual borrowed coin will be dry and ready for use. The remaining portion of the trick will now be understood. When the performer goes for the other half of the programme he takes the packet of envelopes with it and substitutes it as before, and the trick proceeds as described. When collecting the six envelopes for the final effect, the performer palms a duplicate programme which has been lying on his table behind some object, and substitutes this as before when giving the gentleman the envelopes to hand to the lady. * * * * * FILTRATED COIN.--Borrow a half-dollar from one of the company, wrap it up in a handkerchief, and request some one to hold it over a glass of water.