1940 - April - 1st electron microscope demonstrated (RCA), Philadelphia, Pa

In 1940, RCA Laboratories (later merged into SRI) commercialized the first high-resolution transmission electron microscope in North America; this TEM became known as "Model B" and created a usable electron microscope for wider application.

Model B was a behemoth, measuring 10 feet high and weighing in at half a ton. It was demonstrated in Philadelphia on April 14, 1940. The RCA Transmission Electron Microscope was used successfully to observe cancer cells as early as 1949...