The hasp, if that be the name for the double toothed arrangement that catches into the lock, was to be secured by only three brass screws, which seemed to be insufficient, says a correspondent of the Metal Worker; therefore a piece of heavy tin was formed over the front of the trunk, which is only 3/8-in. board, the hasp tinned and soldered to the back of the now U-shaped tin, and the tin placed over the board and all fastened in position.  The tin is 4 in. wide, 16 in. long and when placed over the board, it laps down about 8 in. between the boards, and the same distance inside of the new board, as shown by the heavy line in the cross section, Fig. 1.  Wrought nails are used which pass twice through the tin and both boards, and then well clinched.  The three screws were then put in the hasp.

The knob on the dial extends out too far, which may be filed off and two holes substituted, as shown, with which to operate the dial.  An old key is filed down in the shape shown in Fig. 2 to fit the two holes.

As the dial is convex it will need protection to prevent injury by rough handling.  A leather shield may be used for this purpose, which is cut with two holes, one for the key and the other to permit the operator to observe the numbers on the dial.  The shield answers a further purpose of preventing any bystander from noting the numbers on the dial.

** An electric illusion box [135]

The accompanying engravings show a most interesting form of electrically operated illusion consisting of a box divided diagonally and each division alternately lighted with an electric lamp.  By means of an automatic thermostat arranged in the lamp circuit causing the lamps to light successively, an aquarium apparently without fish one moment is in the next instant swarming with live gold fish; an empty vase viewed through the opening in the box suddenly is filled with flowers, or an empty cigar box is seen and immediately is filled with cigars.

These electric magic boxes as shown are made of metal and oxidized copper finished, but for ordinary use they can be made of wood in the same shape and size.  The upper magic boxes as are shown in the engraving are about 12 in. square and 8-1/2 in. high for parlor use and the lower boxes are 18 in. square and 10-1/2 in. high for use in window displays.  There is a partition arranged diagonally in the box as shown in the plan view, which completely divides the box into two parts.  One-half the partition is fitted with a plain, clear glass as shown.  The partition and interior of the box are rendered non-reflecting by painting with a dull, not shiny, black color.  When making of wood, a door must be provided on the side or rear to make changes of exhibits.  If the box is made large enough, or in the larger size mentioned, openings may be made in the bottom for this purpose, and also used in case of performing the magic trick of allowing two persons to place their