From the June 13, 1936, issue

HUGE SPECTROGRAPH FOR ECLIPSE OBSERVATION

The giant camera shown on the front cover, one of the largest spectrographs ever built, will be used by the joint Harvard-Massachusetts Institute of Technology expedition to observe the total eclipse of the sun on June 19, from a special station at Ak-Bulak, Siberia. The Instrument is made of dowmetal, 96 percent magnesium and 4 percent aluminum, an exceptionally lightweight alloy.