Marine sextant
Astronomy
Navigation
Surveying
Measuring instruments
In the Keuffel & Esser catalog , model 5224D on page 410, cost, $80. Paper label includes model 5224D and serial number 42046. Gun-metal, measuring angles up to 130 degrees, radius 6-in graduated on solid silver to 20 minutes, vernier to 30 seconds. Clamp and transit screw to vernier. Mounting reading lens (missing), 1 plain sighting tube, 1 inverting telescope, 1 star telescope, 2 neutral glasses, 7 neutral glasses to sextant, polished mahogany case with lock. Box has hinged lid, two latches, lock, inside maker label and “obs 143” mark, paper label “2” on exterior.
Keuffel & Esser, New York
Keuffel & Esser Co. (1913). Catalogue and price list of Keuffel& Esser co, manufacturers and importers of drawing materials and surveying instruments. Keuffel & Esser Co: New York.
Astronomy Department, University of Illinois, Urbana, Illinois
About 1915
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A234
University ID 016681, obs143
University of Illinois Observatory, Urbana, Illinois
Heliostat foucault
Astronomy
Optical instrument
Metal, glass
Also Foucault siderostat. Marked “Societe Genevoise, pour la construction, D’instruments de physcique, Geneve.” Wind up drive does not work. Spirit level on black metal base with 3 leveling screws.
Siderostats are used with a fixed telescope, a flat mirror is rotated by a lever arm connected to motor turning once every 24 hours. James Biddle of Philadelphia imported these instruments.
Societe Genevoise D’instruments de physcique (SIP), Geneva, Switzerland
Prix-courant 1900 / Société Genevoise pour la construction d'instruments de physique et de mécanique, Chemin Gourgas, Genève (1900) Genève : W. Kündig & Fils. Page 86.
Astronomy Department, University of Illinois, Urbana, Illinois
1910
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A209
University ID 055343
University of Illinois Observatory, Urbana, Illinois
Engineer transit telescope
Astronomy
Navigation
Surveying
Measuring instruments
Metal, glass, wood
There are two transits. The first is transit includes compass and is marked no. 898. Objective is 1-inch diameter and tube is 8” long. One frosted glass shade is missing.
The second transit is marked no. 862 and comes with a striding level. There is a later aluminum bracket attached to the transit. It also has a 1-inch objective and 20-inch focal length.
P & R Wittstock, Berlin, Germany
Astronomy Department, University of Illinois, Urbana, Illinois
1905-1906
Michael Svec
Copyright by Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A114, A115
University ID 016649 obs10, 016650, obs9
University of Illinois Observatory, Urbana, Illinois
Drum chronograph
Astronomy
Clocks
Measuring instrument
Time recording device
Furniture
Metal, wood, glass
The chronograph, made by Warner and Swasey, is permanently mounted in the clock room. Includes wooden box (9 ¼ x 6 ¼ x 50 ¾ inches) connected to counter-weights and pulleys attached to the ceiling. It consists of a brass cylinder 7-inches in diameter and 14-inches long onto which paper is attached. The driving mechanism is housed to the immediate left of the cylinder. The driving mechanism consists of a spinning governor for regulation and weights to provide the power. A pen is carried on the armature of an electromagnet through which, when current flows, makes a tick mark on the rotating paper. It is possible to measure the time and duration of an event to a hundredth of a second accuracy (depending on how accurately the clock is set).
The weight driven gears still work although the system needs cleaning. The armature and drum still work. The paint on the chronograph is cracking.
The chronograph is connected to the Observatory’s clocks, which provide tick marks every second, and to a key, usually by a transit telescope. An astronomer hits the key when an event occurs and a tick mark is left on the paper with the second tick marks. By recording events this way astronomers can concentrate on the telescope observations and can read the times from the paper at a more convenient time. The chronograph continued to be use in association with the clocks through the 1960s for timing lunar occultation’s and transits.
Warner & Swasey Company
Todd, David P. (1897) A New Astronomy. American Book Company: New York. Page 213.
Astronomy Department, University of Illinois, Urbana, Illinois
1896
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A116
University ID 016668, obs36
University of Illinois Observatory, Urbana, Illinois
Mercury stick barometer
Astronomy
Weather instrument
Barometer
Measuring instrument
Wood, metal, glass, mercury
Housed in wooden box with glass sides, hinged wood/glass door, case is 9 ¼ x 6 ¼ x 50 ¾ inches. Originally kept in the entrance hall on the west wall, just north of the door to the transit rooms. Glass on front door broken.
Consists of mercury in a glass tube encased by chrome and brass tube. Provided with two scales read with a vernier to 0.002 of an inch and 0.05 mm. Range is 66 mm to 83 mm and 26 in to 32.5 in. Vernier moved by turning an attached wheel. Thermometer mounted on barometer measures temperature of the mercury in Centrigrade. Barometer is 45 inches long. Suspended to Mahogany board by a hanger at the top with steadying screws at the bottom cistern. White opal glass plates attached to board for reading the instruments. Inscribed on cistern with “Henry J. Green, New York,” the number 3603 on thermometer and number 3138 on the mercury scale.
The barometric pressure and the temperature were two important factors in determining the atmosphere’s index of refraction. The index of refraction was necessary for transit observations.
Henry J. Green & Company, New York
Astronomy Department, University of Illinois, Urbana, Illinois
1896
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A129
University ID 016673, obs79
University of Illinois Observatory, Urbana, Illinois
Cabin sidereal clock
Astronomy
Clocks
Aluminum, brass, glass
There are two sidereal clocks, both are electric. The first is 9 ½-inch diameter with a 8-inch dial, black metal base, brass and glass, 3 hands.
The second smaller clock 5 ¼-inch diameter, tag indicates a date of 1966.
A 1953 ad shows the electric sidereal clock with a rating of less than one minute slow in 16 years. Cast aluminum case with bronze bezel for $40.
Haines Scientific Instruments, Englewood, New Jersey
Astronomy Department, University of Illinois, Urbana, Illinois
about 1966
Michael Svec
copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A225.1, A225.2
University of Illinois Observatory, Urbana, Illinois
Reflection horizon
Astronomy
Navigation
Surveying
Measuring instruments
Black glass ground plane surface, 3 3/8 diameter, 3 leveling screws, fine graduated adjustable spirit level, and mahogany case.
In the 1913 Keuffel & Esser catalog (page 413) the reflecting horizon cost $16. The reflecting horizon is an alternative to the mercury artificial horizon and is used with a sextant when the horizon is not visible.
Keuffel & Esser Company, New York
Keuffel & Esser Co. (1913). Catalogue and price list of Keuffel& Esser co, manufacturers and importers of drawing materials and surveying instruments. Keuffel & Esser Co: New York.
Astronomy Department, University of Illinois, Urbana, Illinois
about 1915
Michael Svec
copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A226.1, 226.2
University ID 016680 obs142, 016682 obs144
University of Illinois Observatory, Urbana, Illinois
Collimator lens and meridian mark
Astronomy
Optical instrument
Metal, glass
Measures 8 ¼ x 6 x 11 ½ inches, lens is 1.7” in diameter.
Director G.W. Myers articulated the need for a Meridian or mire Mark in a March 6, 1897 letter to university President Draper. “Mire mark and Collimator for 3-inch Combined and Transit and Zenith Telescope.” The collimator was mounted in the north window of the east-central transit room on a brick pier, cased in wood above the level of the floor, with a wooden box as a cover. The wood reduces the impact of the brick’s radiant heating. The meridian mark was located on a distant pier north of the building at the focal point of the collimator lens. The Meridian mark was removed with the construction of Smith Hall (1917), the pier for the collimator was removed during the 1956 expansion of the Observatory. At the Elgin Watch Company Observatory (Illinois), there was also a 3-inch Warner & Swasey transit with a meridian mark 100 feet to the north consisting of a metal plate with a hole three thousandth of an inch in diameter serving as an artificial star.
Warner & Swasey Company
Payne, W.W. (1927 January) Elgin Observatory. Popular Astronomy. 35 (1) 1-9.
Astronomy Department, University of Illinois, Urbana, Illinois
1897
Michael Svec
Copyright by Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A136
University of Illinois Observatory, Urbana, Illinois
Master clocks
Astronomy
Clocks
Measuring instrument
Wood, glass, metal
They are model 25 IBM Master clocks. There are two 60 beat with a Graham dead-beat escapement with micrometer adjustment. Magnet wound, spring drive, self-regulating movement, 63 1/6” x 19 ¼” x 7 5/8”, plain glass door, 12” Arabic dial, white with black numbers, separate hours and smaller seconds circle. There is a one second switch as well as a 59 second switch. Pendulum is a mercurial compensating pendulum, 45 5/16 inches long and approximately 11.5 pounds, accurate to 10 seconds over a 30-day period. The standard time clock has the original mercurial pendulum with two cylinders. The sidereal clock pendulum is a replacement Invar pendulum with one cylinder. Clocks are automatically wound with reserve power for approximately 12 hours. Clocks are housed in a walnut wood case with a glass door and two locks.
A=central standard time (south side of pier), B=local sidereal time (east side of pier). Clock serial numbers are 462905 and 462904.
Included in the purchase order was the new switching wiring and metal storage cabinet and control panel outside the clock room. Paper instructions included.
These clocks replaced the original 1896 Clemens Riefler clocks both of which are now part of the Alder Planetarium collect.
IBM
Astronomy Department, University of Illinois, Urbana, Illinois
1954
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A211.1, 211.2
University ID 196631A, 196631B
University of Illinois Observatory, Urbana, Illinois
Reflection galvanometer
Electrical apparatus
Measuring instrument
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. An unpublished photograph in the Jakob Kunz papers, University Archives, from the 1918 eclipse expedition shows this galvanometer sitting on a shelf in the background. A published picture from 1910 and another unpublished photo from 1912 show the same galvanometer.
Weston Electrical Instruments Company, New, New Jersey
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1908
Michael Svec
Copyright Michael Svec
Harvard Collection: http://waywiser.fas.harvard.edu/objects/2183/reflecting-galvanometer-with-moving-coil
image/jpg
English
physical object
University of Illinois Observatory Collection A193
obs52
University of Illinois Observatory, Urbana, Illinois