Aircraft Armament Past And Present, Part 1. Machine Guns And Mountings, Invention Of The Synchronising Gear'. P/b, 14 x 22cm, 15p. Published by Real Photographs Co Ltd. Wartime publication with information on the early WW1 Lewis guns to the 'modern' WW2 Browning. Illustrated throughout with photographs and diagrams. Good condition. Stock code P20571.