Harry Brearley
Harry Brearley (18 February 1871 – 14 July 1948) was an English metallurgist, usually credited with the invention of "rustless steel" (later to be called "stainless steel" in the anglophone world).
Christopher Miner Spencer
Christopher Miner Spencer (June 20, 1833 – January 14, 1922) was an American inventor, from Manchester, Connecticut, who invented the Spencer repeating rifle, one of the earliest models of lever-action rifle, a steam powered "horseless carriage", and several other inventions. He developed the first fully automatic turret lathe, which in its small- to medium-sized form is also known as a screw machine.