Stress tests for Department of Commerce, Southern California, 1931

12 photographs of stress tests on airplane components for the Department of Commerce, Cycloplane Co., Southern California, 1931. "Subject: Stress tests for Dep[artmen]t of Commerce; Client: Cycloplane Co.; Original print order: 1 ea[ch]; Size: 8x10; Finish: gl[ossy]; Re-order: 1 ea[ch]; Size: 8x10; Finish: gl[ossy]; Year: 1931; Job: 5-25-162" -- on envelope front. "Extra charges: Meyres; Hours: Regular, 2 1/2, 2.00, 5.00; Ounces of flash powder: 2 at 85¢, 1.70; Original photographs-Size: 12, 8x10, (2 trips), In City, 12.00; Operator's report (Name): Dick" -- on envelope back.