Lantern slide 'U of I 30 inch reflector'
Title
Lantern slide 'U of I 30 inch reflector'
Subject
Astronomy
Photography
Optical instrument
Telescope
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.
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.
"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
Collection
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.