Page:Pyrotechnics the history and art of firework making (1922).djvu/160

 quantity" of chlorate of potash and sugar. An explosion resulted which blew out the entire window frames of the room, destroyed the partition between the room and the passage, considerably damaged the other wall, and projected the pestle into the ceiling, where it remained embedded.

Accidents at displays are now happily rare; the most fruitful cause of such happenings was the detonation of shell in the mortar, that is, the detonation of the contents or "garniture" by the explosion of the propellant charge.

The elimination of chlorate-sulphur composition has reduced the chances of this to a minimum, and the compulsory burying of mortars up to the muzzle has practically eliminated the danger to either firers or spectators.

Apart from slight injuries caused by falling rocket sticks and mishaps of a similar nature, accidents to the public at firework displays are things of the past.