Lantern slide 'U of I 30 inch reflector'

Title

Lantern slide 'U of I 30 inch reflector'

Subject

Astronomy
Photography
Optical instrument
Telescope

Description

Lantern slide of the 30-inch reflecting telescope purchased in 1914. The mirror had a focal length of 20-inches and was made by John Brashear. The mount might also be by Brashear. This lantern slide is part of the Observatory's collection and is marked "O 60."

According to a 1914 article in the Urbana Daily Courier, the telescope "has been in use in Washington D.C. for some time but is now in the Metal Shop awaiting the completion of the new observatory where it will be installed. The telescope has been used for condensing the rays of the sun onto a mirror. The instrument has been used to melt platinum which requires about 1775 degrees Centigrade. The mirror was a diameter of thirty inches. The focus is very short so that there is a maximum of light-gathering properties making it a huge burning glass. It has been set up at the Metal Shops and carefully tested. It was constructed by the John Brashear Company of Pittsburgh." The goal for this new telescope was to have it equipped with a photoelectric photometer.

Creator

Photographic department, University of Illinois

Source

Baker, Robert H. "The 30-inch Reflecting Telescope and Photoelectric Photometer of the University of Illinois." Popular Astronomy. 122:86-91.

"University buys big telescope" (August 5, 1914) Urbana Daily Courier, page 3.

Publisher

Astronomy Department, University of Illinois, Urbana, Illinois

Date

circa 1914

Format

still image

Language

English

Coverage

University of Illinois Observatory, Urbana, Illinois

Original Format

Lantern slide

Physical Dimensions

3 1/4 x 4 inches

Files

30inch1915.jpg

Collection

Tags

Citation

Photographic department, University of Illinois, “Lantern slide 'U of I 30 inch reflector',” University of Illinois Observatory Collection, accessed March 28, 2024, https://uiobservatory.omeka.net/items/show/44.