Browse Items (5 total)

DSCN0180.JPG
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.

IMG_5798.JPG
The photocell is hand blown glass or quartz. Within in the cell is an alkali metal (lithium, sodium, or potassium) that covers the inside and is a cathode emitting electrons when illuminated. A well insulated wire forming a ring centered in the…

DSCN0183.JPG
Model no. 89, no. 18. Box is 8 ¼ x 8 ½ x 12 inches and screwed closed. Unknown date but estimated around 1908. Used with the selenium cell photometer to measure current and with the photoelectric cell photometer. Visible in pictures of transit room. …

DSCN0189.JPG
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.

Tags:

DSCN0018.JPG
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…

Tags:

Output Formats

atom, dcmes-xml, json, omeka-xml, rss2