Historic Films compilation: McGregor Tower Dome; Clarkston swimming & Pete moon; 50 Foot Tower; Leo Goldberg's Picture of Portage Lake & Harry Hulbert, 1949
Footage of the construction of the observatory. Includes: Placing dome on McGregor Tower [1940][D.O. no. 272]; Clarkston swimming & Pete moon [1928] [D.O. no. 273]; 50 Foot Tower [undated] [D.O. no. 274]; Leo Goldberg's Picture of Portage Lake & Harry Hulbert [1949] [D.O. no. 275].