 Forsyth had noticed that sitting birds would startle when smoke puffed from the powder pan of his flintlock shotgun, giving them sufficient warning to escape the shot.His invention of a fulminate-primed firing mechanism deprived the birds of their early warning, by avoiding the initial puff of smoke from the flintlock powder pan and shortening the interval between the trigger pull and the shot leaving the muzzle.Fulminate-primed guns were also less likely to misfire than flintlocks; it was not until after Forsyth's patents expired that the conventional percussion cap system was developed.