I only just realized that this chart was edited by Arthur Compton, Nobel prize winner and the discoverer of Compton scattering! In 1944, hmm -- seems that his job in the Manhattan project left him with some spare time? ;-)
Anyway, I need to get me a poster printed! Nice to know the original dimensions from the ebay auction (58" * 41"); although I may not want mine quite as large.
Edit: Found this description of the poster's history, which dates the original edition to 1936. It also states (not unexpectedly) that Arthur Compton mainly gave his name, while the publisher and an assistant of Compton's did the actual editing:
http://physicsbuzz.physicscentral.com/2013/09/making-chart-of-electromagnetic.htmlThanks, Ed, for the link to the color-restored version. I quite like that one!