The particular advantages of this flash lamp are; - It may be operated from any location, and at any time desired by the operator without others having previous notice of when the lamp will flash. It is thus possible for the operator to be included in a group, and the peculiar contraction of the eyes so characteristic of most flashlight pictures is avoided, as any oppertune moment can be utilized for the flash.

The novel feature of this lamp is the use of an electric magnet for releasing the trigger, the latter working much after the fashion of a mouse trap. The horseshoe magnet M can be taken from an electric bell. It is mounted upon a wooden base B which measures 12" long, 5" wide and 3/4' thick. A hole will be found in the centre of the bar connecting the two coils of the magnet. Through this hole put a small screw attracting the magnet to the frame holding the arm A. This frame is made of two pieces C, 8" long, 5/8" wide and 1/4" thick, nailed to the piece D which is 1 1/2" long, 1 1/4" high and 5/8" thick. It is attached to the base board by two screws of small guage put through from the under side of the latter. Holes for the wire nail N are bored in the pieces C, 2" from the bottom ends. Two small tacks T are driven into the upper ends of C, to which fasten a light rubber band R, which when slightly stretched will engage in the notch in the lower part of the arm A.

The brass or iron wire arm A is 2 3/4" long on the horizontal section, and 4 3/4" long on the vertical. In cutting, also allow for two turns to go around the nail N with a loose fit, and a turn at the upper end to hold a tuft of asbestos wool or cotton wicking. The end at the triger is hammered out flat and then tiled smooth, but no bevel on the top side. A notch for the rubber band is bent in the centre of the horizontal part as shown.

The trigger is made of the armature G of soft iron, also taken from the electric bell. The hammer of the bell is an extension of this armature. The surplus pieces are removed as only the armature is needed. A piece of iron wire H is fitted to a hole drilled in the centre; two turns are made 5/8" above the armature to fit around a nail shaft as before described, and 1/8" of the upper end is bent at right angles, 5/8" above the centre turns. Two supports F are 2 1/2" high, |" wide and 1/4" thick, 3/4" of the lower ends being cut down to fit 1/4" holes in the base bored to receive them. Holes are bored in these supports 1 3/8" above the base for the nail 0, but this should not be done until all the parts described are in position so that the trigger may be located in just the right place. The two wires from the magnet are each carried to connecting springs S made of short pieces of spring brass, a hole being bored in one end to receive a round head brass screw under the head of which is carried a wire from the magnet. The ends of other wires connecting battery and push button can be readily placed under the ends of these springs when connecting up for the work.

The powder pan P is made of tin, (that taken from an old preserve can will serve) and is 8" long, 3" wide and 1/4" deep. It is attached to a block of wood W 1/2 thick, by a round head screw located on one side so that it may be turned to be in line with the base board when not in use. The block W is curved on the rear side to an arc fitting the reflector V. The reflector is made from a bright piece of tin from a fresh preserve can, and is 6" high, and 8" long. On the lower edge three lugs 1/2" wide and long are left, one in the centre and one near each end, which are turned toward the front and are pushed between the block Wand the base, holding the reflector upright when in use and yet allowing easy removal for packing up. At the centre of the reflector a slot 1/2" wide is cut from the top nearly to the bottom, for the arm A to drop through.

To operate, the terminals S are connected by flexible wire to battery and push button as follows ; run a wire from one terminal S to zinc of a dry cell; from the carbon of cell run wire to push button; from the other terminal S run wire to push button. Put the flash power on the tray P spreading it along in a line so it will not all fire at once, but make a running flash. The tuft of asbestos on the arm A being wet with alcohol, the trigger is set and the alcohol lighted. By pressing on the push button, the circuit will be completed, the magnet will attract the armature G, releasing the arm, the rubber band will pull the arm over so that the weight of the upper part will cause it to continue falling until it reaches the powder and flashes it.

The length of the connecting wires is as may be desired by the operator. If one dry cell does not furnish sufficient current to attract the armature use two. A few trials without powder will enable any needed adjustments to be made.