Physical apparatus


Physical apparatus


In addition to equipment attached to the telescope, astronomers, especially in the "new astronomy," often had laboratory equipment that could be found in a physics laboratory. Much of this equipment at Illinois was related to the development of photoelectric photometry. The photometer turned the star's light into electric current and much of this equipment was need to measure the electrical output of the photometer.


Department of Astronomy

Items in the Physical apparatus Collection

Reflection galvanometer
Model no. 89, no. 18. Box is 8 ¼ x 8 ½ x 12 inches and screwed closed. Unknown date but estimated around 1920-1925 although could be earlier. Used with the selenium cell photometer to measure current and with the photoelectric cell photometer.

Reading telescope
Metal, glass

Eyepiece with crosshairs, 12-inch tall, 11-inch long, tube 1-inch outer diameter, missing an objective lens.

Used with galvanometer to read the reflection off the mirror.

DC Voltmeter
Wood, metal, glass

Weston DC voltmeter model #38635, dated September 1, 1923. Two scales 0-15 and 0-150. Box measures 7 ½ x 4 ½ x 7 ½ inches. Scale has mirrored scale.

DC Voltmeter
Wood, metal, paper, glass

Model 45, No. 32664, in oak box measuring 7 7/8 x 5 3/8 x 7 7/8 inches, with leather handle, 2 scales 0-150, 0-15. Paper label dated November 5, 1926. All hardware is nickel-plated brass. The front panel and meter face…