Volume 23, Issue 4 - February, 1940. Mechanical science and technology magazine. This issue's articles include; "How to Bowl" by Joe Falcaro, "Your Job - Radio Servicing" by Donald G. Cooley, "Can This War Be Won?" by Maxwell Hamilton, "Riding the Frozen Freight" by James Montagnes, "Want to Buy a Rattlesnake?" by Harry Pederson, and others. 6 1/2-in. x 9 1/2-in., 146 pages, BW/spot color.
Cover price $0.10.