Complex sentence: During the Napoleonic Wars Forsyth worked on his design at the Tower armories but when a new Master General of Ordnance was appointed he was dismissed; other experiments had had destructive results and the new master general did not wish to see Britain's main arsenal destroyed.
Split into simpler sentences: During the Napoleonic Wars Forsyth worked on his design at the Tower armories. But when a new Master General of Ordnance was appointed he was dismissed; other experiments had had destructive results and the new master general did not wish to see Britain's main arsenal destroyed.