ble to keep it from freezing until it reaches a chemical rays, and serves for photographing. As the by a system differing in toto from any of those at pres- temperature of 15 degrees. Under other conditions optical axes of these two objectives are parallel, every ent employed. such a temperature… … it deviated from the course traces of stars of the fifteenth Fig. 3.-PAR AIL ACTIO APPARATTTS AT THE PARIS OBSERVATORY, upon which it had been laid, magnitude, that are too faint- the electro magnetic arrange- ly indicated to show up in the ment—which was, of course, concealed within the tor-…
