Alexander John Forsyth (28 December 1768 – 11 June 1843) was a Scottish Church of Scotland minister, who first successfully used fulminating (or 'detonating') chemicals to prime gunpowder in fire-arms thereby creating what became known as percussion ignition.

These men included Joseph Egg, James Purdey, Col. Peter Hawker and the British born artist Joshua Shaw.

In the face of so much competition, Shaw decided to travel to America in 1817 and, once he was legally allowed to do so, was granted an American patent for a percussion cap in 1822.

Shaw made a series of claims of being the inventor in order to gain compensation from the U.S. government for their use of copper caps without permission.

[8] These new forms of ignition proved popular among sportsmen during the Regency period, who had their old unreliable flintlocks converted.

[10] He patented his scent-bottle lock in 1807; this was a small container filled with fulminate of mercury[11] During the Napoleonic Wars around 1806, Forsyth worked on his design at the Tower Armouries.

The French gunsmith Jean Lepage developed a similar form of ignition in 1807 based on Forsyth's design, but this was not pursued.