It is sometimes desirable to produce a flash when only magnesium powder is at hand and there is no suitable lamp available, says Fayette J. Chute in "Camera Craft." At other times the matter of expense may be an item, and for that reason the following plan, which is both cheap and effective, may be of use:
Soak some thick blotting paper in a saturated solution of saltpetre and allow to dry. One has then only to place a small piece on the top of a piece of tin or other safe material; place a little magnesium powder in the center and fire by applying a match to the corner. The lighted match can be held by making a split in the end of a long pine stick or lath. The length of the flash is much less than that secured with an ordinary blow-through lamp, particularly when the powder is in a thin layer. Heaped up, the powder requires longer to burn, but there is some waste. Spread in a train the time is extended and a larger amount of light is secured from a given amount of powder than when it is heaped up. The plan is entirely satisfactory, and there is less smell and smoke occasioned than with many of the expensive compounds offered the worker.