Science Art: Power of RCA Electron Microscope, May 1955

These are diatoms, I think, seen by two different microscopes.

As the caption from Popular Electronics says (found here, on archive.org):

A fossil particle was magnified 3000 times by a conventional light microscope, and then by the electron microscope. The electron micrograph (right) is sharp, clear, and detailed. RCA’s newest unit provides magnification up to 200.000 diameters— 50 percent greater than previously possible.

It’s from an article describing “one of science’s most powerful weapons in its attack on the frontier of the unknown,” tracing the electron microscope’s history back to 1873… using “practical electronic lenses.”