This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
The effect of this trick is as follows: A small metal box, just large enough to hold a half dollar and about 1/2 in. high, with a cover that fits snugly over the top, is passed out to be examined, and when handed back to the performer he places it on the finger ends of his left hand, and a half dollar is dropped into it and the cover put on. The box is then shaken to prove that the coin is still there. The performer then taps the box with his fingers and picks it up with the other hand and the coin will appear to have fallen through the bottom. Both the coin and box are then handed out for examination.
This seemingly impossible effect is made when the performer places the cover on the box. The box is resting on the fingers of the left hand and the cover is held between the thumb and forefinger of the right hand, but just before placing the cover on, the box is turned over with the right thumb, and the cover is placed on the bottom instead of the top.
The trick can be done within a foot of the spectators without their seeing the deception. It is a good plan to hide the box with the right hand when placing the cover, although this is not necessary.