Lewis Gunner, Duke of Wellington's Regiment, 4th Div.1918. The Lewis Gun was the first succesful Light Machine Gun : though "light" was a relative term. It's adoption in 1915 transformed squad tactics : in fact might be said to have invented the modern Infantry squad , normally around ten men , including a Light Machine gun. Oddly enough , the despite being an American-designed weapon , the US forces never adopted it , but the British seized on it with relish, and it was manufactured to use thei