William Beaver
A Sheffield directory (1839) listed Beaver as a maker of lock and fly-open knives. The latter were probably automatic (or switch-blade) knives that were destined for the American market. Beaver worked in Upper Edward Street, in a courtyard between Nos. 142 and 144. He was listed in directories in 1837, 1841, and 1845, but remains largely anonymous (though he may have died in 1850).