Color-Vision and Color-Blindness. A practical manual for railroad surgeons.

Philadelphia, F.A. Davis 1896. Octavo, excellent in publisher's cloth; x,115pp and publisher's list, colour frontispiece and 21 illustrations through the text. First edition and pretty much the ideal copy as it belonged to a railway surgeon who wrote on colour blindness: D. Emmett Welsh - then formulating tests for workers at the Grand Rapids and Indiana Rail Road. Jennings' intent here is to effect universal reform and adoption of testing - it is astonishing that by 1896 railway companies and other industries where colour blindness could and did cause disaster still ignored the problem - by offering a system of simple and efficient measures.