Without the percussion cap and the self-contained round, the machine gun would never have been developed. As a minister, the Reverend Alexander Forsyth would perhaps have been horrified to discover his major part in this innovation. It was the method of ignition he invented to make wild fowling less vulnerable to the vagaries of the weather that became a key element of the machine gun. Rounds - the bullet and cartridge with its percussion cap and powder - could be fed on a belt or from a spring-loaded magazine into a rapid-firing and brutally effective weapon of war.