This is a rarely seen back of the Hoover Dam before it filled with water 1936. Hoover Dam is expected to be one of the last…
Tag: construction
On July 17, 1888 Granville Woods received a patent for the "tunnel construction for electric railways" - This Day in Patent History
Patent Information Publication number: US 386,282 Patent Title: Tunnel Construction for Electric Railways Publication date: Jul 17, 1888 Filing Date: May 2, 1887 Inventors: Granville…