Remember that this Manton was not made by the Manton family. In this time they were mainly sold for India.

Manton was the man who brought English gunmaking out of the blacksmith shops. He was the beginning of fine English guns. His first apprentice was a fellow named Purdey who showed some promise. Manton's brother also was a gunmaker but not of the quality on Manton. Manton made the mistake of innovation when he should have stayed with flintlock shotguns (like Purdey when he left Manton to start his own gunworks). Manton experimented with various caplock guns (when they were under patent to others, unfortunately). This caused him legal problems and his business went under. His brother lasted longer. However, the name was sold (like Rigby now) and the name continued on into the 20th Century, I believe.