Joel Stebbins used the selenium cell photometer to study the known variable star Algol. The improved accuracy of the photometer revealed the second minimum and the limb darkening.
Figure 2: Galvanometer and accessories for the selenium photometer. Page 191.
Visible in the photograph are the galvanometer, reading telescope, scale, batteries,Wheatstone bridge, and resistance boxes. Was located in the west-central transit…
Metal black frame with wood handle and silver scale. Horizon mirror is broken, includes 4 index filters, 3 horizon filters, 3 brass telescopes, 2 lens caps, wooden handle, 6” radius on scale, maker and model 4323 marked on index…
Black aluminum frame, wood handle, one telescope, no filters, micrometer wheel on vernier scale, arc is black with white engraved scale from 0 to 140. Marked on index arm “U.S. Navy Bureau of Ships ETS Sextant, Mark 2 Mod 0…
Wooden frame with moveable seat and eight steps on four castors. Measures 45” x 48” x 103” tall. Moving adjustable chair with foot-rest connected to counter weights slides up and down in the middle of the stairs with in a wooden track.…
Gold medallion in 3.5 inches square leather case with green velvet. interior. Metal approximately 3 inches diameter, made of gold. Front contains left facing profile of Lord Rumford. Reads “Born 1753 * Benjamin Count Rumford * Died 1814.” Back reads…
Wood box, 9 7/8 x 9 7/8 x 5 ½ inch, with hinged lid, two hook latches and metal handle. Maker’s laminated paper label and university ID tag on inside. While the last inspection date on this sextant is 1939, the last sextant made…