(Documentary Artifact): One b/w negative of Mr. Kempl grinding the track on the 48′ reflector at the Palomar Observatory. He is partially obscured by beams with only the lower half of his body visible.

Notes on negative envelope:
86:15900-1153/ Davis Coll/ dup. Neg./ Mount Palomar/ Mr. Kempl grinding track on/ 48′ reflector observatory/ Aug. 1938