Top photo,
Karl F. Nystrom
He is probably best known for his work designing and building the Hiawatha trains for the Milwaukee Road.
Second photo,
The 1934 Union Pacific M-10000 streamlined train was designed by Pullman's Martin P. Blomberg, based on design principles adopted from a a 1932 lightweight aluminium Pullman railcar created by aviation designer William Bushnell Stout (who later went to work for Ford).
Third photo,
Everyone knows about the P-38 Lightning and Kelly Johnson!
Fourth photo,
The blowtorch was invented by Carl Richard Nyberg in 1882.