Good morning, Pete;
Oddly enough, many people think that the "FP" flash terminal connector or the "FP" synchronization setting on their camera for flash exposure is for "Focal Plane," but originally it stood for "Flash Powder" up until at least the 1930s. And, you could still buy canisters of Flash Powder into the 1950s. And, with a trickle of flash powder along the full length of the flash tray, the burn time was also long enough to work with the focal plane shutter of such cameras as the Graflex Speed Graphic. It was impressive when it went off, and the usually white smoke did seem to dissipate fairly quickly. The concept of "smokeless powder" among the small arms shooting crowd did not seem to really catch hold with any great popularity among the photographers, and then they began to use the magnesium or zirconium or other wire filled screw base glass bulbs instead in the 1930s, but, yes, they were "smokeless." (It was contained inside the bulb, as long as it did not break.)
Enjoy; Ralph, Latte Land, Washington