Ready References
Beginner's Corner, May 1939
The Art of Using a Telescope
Power and Aperture in Binoculars
Variable Stars Explained
AAVSO Observing Programs
Molding and Casting
Optical Instruments
Ready References 
Beginner's Corner, May 1939 
The Art of Using a Telescope Power and Aperture in Binoculars Variable Stars Explained AAVSO Observing Programs Molding and Casting Optical Instruments