[xoxoxoBruce]

From a very detailed article, on how to build homemade fireworks, from a 1936 Science & Mechanics magazine.

IN making fireworks, if the experimenter will always remember that he is dealing with explosives that may pop off at any moment, and therefore exercises constant caution, the various spectacular night displays outlined in the accompanying article are not any more dangerous than playing with matches. At all times, care must be exercised in grinding the ingredients. Always use a clean mortar; always powder each chemical separately; when mixing, dump the required portions on a sheet of dry paper and use a wooden spatula, or gently rock the contents of the paper back and forth. Although the author is only fifteen years old he has been making fireworks for years and has not yet had one of them go off accidentally. The formulas contained in this article have all been tried and tested, and will be found to work perfectly.