Vintage photos of:
Detroit circa 1906. "Detroit Publishing Co., northwest view." Note the greenhouse-style glass to the right employing sunlight for printing and perhaps enlargement, as well as the unusual windows to the left. In the early years of the 20th century, the company was one of the world's biggest producers of color postcards. Panorama made from two 8x10 inch glass negatives. View full size.
Washington, D.C., circa 1924. "Brent Daniel, formerly of the Radio Laboratory of the Bureau of Standards at Washington, with the first portable Super-Heterodyne, his own design. The seven vacuum tubes, batteries, loop antenna, loudspeaker and other necessary units are completely self-contained in the carrying case. He has been able to hear Pacific Coast stations from this outfit." View full size.