Smithsonian Magazine on MSN15 小时
Chaotic Traffic From Horse-Drawn Carriages Inspired the World’s First Traffic Lights
Initial reactions to the signal, installed in London on this day in 1868, were mixed. Then, a freak accident scrapped the ...
Hackaday12 年
Semaphore Signal Replica Perfect For The Train Buff In Your Life
Rather than construct something for the railroad itself, he decided that an early 1900’s-style semaphore railroad signal would make a great novelty item for the room. The project started with ...