Window transparencies
Astronomy
Photography
Furniture
Wood, glass, film
Black rectangular frame with two metal eye hooks on the top. Hung in window, wooden frame, image of moon sandwiched between two pieces of glass and a light diffusor. Illuminates print using light from outside. Seven were made locally from transparencies in 1907. On many pictures from the period, you can see the transparencies hanging in the windows in the foyer, and in the south windows of the classroom. One is a black and white photograph of M33. The second is the Moon, specifically Crater Theophilus in center, Mare Nectaris on left. Picture taken with 40-inch refractor at Yerkes Observatory by Ritchey. Published in The Popular Science Monthly, February 1902, page 312 illustration 13.
Unknown
Astronomy Department, University of Illinois, Urbana
circa 1907
Michael Svec
Copyright, Michael Svec
image/jpg
English
physical object
University of Illinois Observatory, Urbana, Illinois
Willis Pendulum Astrolabe
Astronomy
Navigation
Surveying
Optical instrument
Measuring instrument
The Willis Pendulum Astrolabe was used primarily by the armed forces to determine latitudes and longitudes. The astrolabe is stored in a large green wooden box. It is marked “PENDULUM ASTROLABE David White Co. Milwaukee Wisc USA, No. 65649, M-5107, 1952, U.S.” The instrument was invented by John Willis> The advantage of the Willis pendulum was that it used a mirror instead of mercury as a reflecting surface. It was able to measure position on earth to within 20 feet. The David White Company was founded in 1895 and continues to provide precision optical tools used in surveying.
David White Company
University of Illinois, Astronomy Department, Urbana
Circa 1952
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory, Urbana, Illinois
Visual spectroscope
Astronomy
Measuring instrument
Optical instrument
Spectroscope
Wood, brass, glass
Comes with large wooden box with hinged lid (24” x 14” x 8”), 12”tall stand (obs 726), and accessories. It includes a dense flint prism and a reflection diffraction grating. Crosshairs and a precise scale permit the measurement of position of the emission or absorption lines to an accuracy of 6.5 Angstroms with the prism and 3 Angstroms with the diffraction grating. Slow motion arm is damaged, soldering makes attaching to the stand difficult.
In Stebbins’ notebook, “One second size astronomical spectroscope with circle and slow motions, one 1-inch grating, one dense flint prism with minimum deviation, without micrometer. Final bill June 29 $200.”
“The curves are based upon the normal solar spectrum produced by a small grating spectroscope attached to the 12-inch refractor. The center of the sun’s image was kept on the slit of the spectroscope, . . . The spectroscope is a modest affair, being next to the smallest size regularly manufactured by Brashear. The ruled surface of the plane grating is 19 x 25 mm and the objectives of the collimator and view telescope are each of 19 mm aperture and 285 mm focal length.”
Cleaned by J.W. Fecker in 1954.
John Brashear, Pittsburgh
Stebbins, J. 1907. The color sensibility of selenium cells. Astrophysical Journal. 26, 326, 183-187.
John A. Brashear Company LTD. (1906). Catalogue: Optical, physical, astrophysical and astronomical instruments. John A. Brashear Co. LTD.: Allegheny PA.
Astronomy Department, University of Illinois, Urbana, Illinois
1907
Michael Svec
copyright by Michael Svec.
image/jpg
English
physical object
University of Illinois Observatory Collection A132
University ID 016671, obs67
University of Illinois Observatory, Urbana, Illinois
Visual polarizing photometer
Astronomy
Measuring instrument
Optical instrument
Photometer
Wood, brass, glass
Wooden box with hinged lid, barlow adapter, brass ring. Box measures 30” x 9” x 9”. The photometer is 24” long.
The visual photometer utilizes the polarizing properties of doubly-refracting crystals to measure stellar magnitudes. It is used on double stars where one of the stars has a known magnitude.
“The polarizing photometer used in these observations was constructed by Alvan Clark & Sons. It is of the form devised by Professor Pickering and described by him in Annals of Harvard College Observatory, Vol.11, page 4, where it is designated as ‘Photometer H’. A Wollaston prism forms two images of each star, and these images are varied in intensity by rotating a Nichol placed between the eye and the eyepiece. . . This instrument is capable of extremely accurate results, bit its use is limited to those stars which are closer than about 100”"
Used by Stebbins to observe double stars in 1904-06 and Delta Cephei in 1907 leading to pioneering work by on measuring brightness using electricity making visual photometry obsolete. After Stebbins left in 1922 with the photoelectric photometer, C.C. Wylie resumed using the visual photometer to study WW Aurigae and Delta Cephei. It was used in the 1950s and early 1960s for instruction after a cleaning by J.W. Fecker in 1954. In 1957 Robert Tull and in 1961 Robert Roeder prepared instructions on the photometer’s use.
Alvan Clark & Sons
Stebbins, J. (1907, July) Photometric observations of Double stars. The University Studies, vol, 2, no. 5. University of Illinois Press.
Stebbins, J. (1908). The light-curve of δ Cephei. Astrophysical Journal, 27, 188-193.
Wylie, C.C. (1925). Note on the eclipsing variable WW Aurigae. Popular Astronomy, 33:600-601.
Report of observatories. (1924). University of Illinois Observatory. Popular Astronomy. 32:98-99.
Astronomy Department, University of Illinois, Urbana, Illinois
1899
Michael Svec
copyrighted by Michael Svec.
image/jpg
English
physical object
University of Illinois Observatory Collection A131
University ID 016670, obs 66
University of Illinois Observatory, Urbana, Illinois
Sidereal clock, no. 22
Astronomy
Clocks
Measuring instruments
Wood, metal, glass
Wooden mahogany case, there was a spare wooden case, height 59.25 cm, width 44 cm, depth 20 cm. There are two front glass doors, one for the dial and one for the pendulum. The sides are wood paneling for the pendulum and glass for the top portion showing the mechanism. Details on Riefler clocks can be found on page 36 of this catalog. On the left of the dial it reads; “C Riefler, DRP No 50739 no 22” and on the right side of the dial “Munchen DRP No 60059 1896.” The number DRP 50739 is the German patent number for the escapement and DRP 60059 is the German patent number for the mercury compensating pendulum. The pendulum consisted if a steel tube filled 2/3 with mercury and a thin steel bob weighing several kilograms. The dial for the large hand is for minutes. The top smaller dial is for seconds marked in 0-60. The bottom dial is for hours, marked 1-12 in roman numerals.
The clock is now in the collection of the Adler Planetarium in Chicago
"The Riefler clock has two interesting characteristics. The first consists in the peculiarly simple and effective compensating pendulum, and the second in the mode of suspending the pendulum.
“As is well known, any good compensating pendulum should have as few parts as possible, should take up changes of atmospheric temperature with equal rapidity in all its parts, should have its compensating material extending as nearly throughout the length of the pendulum as possible, and finally should be heavy and have an appropriate form. How nearly Riefler's pendulum satisfies these conditions can be inferred from the following description:
“Its consists of a hollow steel tube 4 ft. 2 in. long, 0.65 of an inch inside diameter, with its wall 0.04 an inch thick. The tube is filled with mercury to a height of about two-thirds of its length. At the lower end is attached, by a screw with a milled head, a heavy lens-shaped mass of brass whose form permits it to cut its way through the air with almost no resistance. Below the lens are smaller disk-shaped masses whose number and position may be varied for somewhat finer regulation of the rate than can be effected with the milled head. These disks are also used for regulating either to sidereal or mean solar time. At about two-thirds of the height of the pendulum is a light brass cup for the reception of small weights that may be put on or taken off for the most delicate alterations or rate, without disturbing the vibrations of the pendulum.
“The second special feature is the peculiar mode of suspending the pendulum. Its weight is carried by a frame resting by knife edges on agate surfaces. By means of a pair of thin steel springs the two parts into which the pendulum tube is divided near its point of suspension are connected at a distance about one-half inch apart. Through these springs the oscillations of the pendulum communicate a rocking motion to the frame and also to an arm extending downward, terminating in a fork either prong of which carries an agate pin. These pins engage alternately into the tooth wheel of the escapement. The rest of the mechanism of the escapement offers no features especially different from the ordinary form. By means of a pair of screws at the extreme top of the pendulum, the relative lengths of to and fro vibrations may be regulated. The clock is also provided with break circuit attachments and chronographic connections."
The first Riefler clock was designed in 1890 in consultation with Hugo von Seeliger, director of the Munich Observatory. Professor G.W. Myers did his dissertation research under Seeliger in Munich between 1894 and 1896. By 1900, 230 of the mercury compensation pendulums had been sold.
Clemens Riefler of Munich, Germany
Myers, George W. "The Astronomical Observatory of the University of Illinois." Popular Astronomy. 6 (1898) 319-321.
Special catalogue of the joint exhibition of German mechanicians and opticians. (1900). Berlin: Reichsbruckerei.
Adler Planetarium, Chicago, Adler: Accession number A-189
1896
graphic image from catalog
English
physical object
University of Illinois Observatory, Urbana, Illinois
Sextant and artificial horizon
Astronomy
Navigation
Surveying
Measuring instruments
Wood, metal, glass
Sextant:
Wooden box with hinged lid, inside includes Keuffel & Esser paper label and “obs 15” mark. Sextant matched with artificial horizon A214.2.
Black metal frame, wood handle, silver scale, maker marked on index arm, 2 telescopes, long tangent screw, 2 lens cap filters, reading lens for vernier, 4 index filters and 3 horizon filters. No 22872, maybe model 5225.
Artificial Horizon:
Box has hinged lid with two latches, broken leather handle, is marked with a maker tag, number 5 and University id tag and with a University police evidence tag from 1981. Bronzed brass roof with greenish color, measured 8 ¾ x 7 3/8 x 4 ½ inch high, fine plane glass 2 ¾ x 4 1/8, iron mercury bottle with threaded stopper and funnel top. Iron mercury trough with thread for funnel and lip. Polished mahogany case. In the Keuffel & Esser catalog #5250 on page 412, cost $35 .
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
circa 1913
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory, Urbana, Illinois
Sextant and artificial horizon
Astronomy
Navigation
Surveying
Measuring instruments
Wood, metal, glass
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 arm, vernier read by magnify lens.
Box is 9 5/8” x 9 5/8” x 5 ¼” with hinge top, two latches, lock, marked “obs 14,” with metal handle.
Acquired in exchange for small Fauth chronograph. Saegmuller joined Bausch and Lomb. In 1905, the company included all three names until 1907.
The artificial horizon:
Wood, metal, glass
In the Astronomy department is the box with the cover, marked Fauth & Co. Box is 8 3/8” x 6 ¼” x 5 ¾”, dove tails visible, 2 hook latches, exterior university id tag plus paper label #6 .. Both the tray and bottle are corroded. Wind shield is greenish metal and glass. A
The artificial horizon was used with sextant to determine the altitude of objects when the true horizon was not visible. They most commonly consist of a trough, bottle with mercury, and a wind shield consisting of two panes of glass at right angles to the observer’s line of sight. It was used by viewing the sun or star directly and then again in the reflection of the mercury surface. You would then have two measurements can could divide by two. In the Saegmuller catalog (page 63) it cost $30.
Bausch, Lomb, Saegmuller Company and Fauth Company
Astronomy Department, University of Illinois, Urbana, Illinois
1906
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A119.1
University ID 016654, obs14
University of Illinois Observatory, Urbana, Illinois
Sextant and artificial horizon
Astronomy
Navigation
Surveying
Measuring instruments
Wood, metal, brass
Hinged box with lock, missing handle, inside lined with green felt, green paper Newton label. University tag crossed out in pen.
Sextant valued in 1908 estimated $50. Engraved on arc “Newton + Co 3 Fleet Street London.” Black metal frame, wood handle, silver scale. Includes 4 brass telescopes, 1 eyepiece cover, scale is 8” in radius, 4 index shades, 3 horizon shades, vernier read with eyepiece.
The artificial horizon:
Hinged box with two hooked latches. Exterior marked with university ID tape, old paper sticker with number 1 and more modern paper tag “7 (no Hg).”
Contained green metal shield with glass, engraved with direct, tray with some corrosion, and metal bottle.
Newton & Company, London
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1872
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A118.1, 118.2
University ID 016653, 016653B, obs13
University of Illinois Observatory, Urbana, Illinois
Sextant
Astronomy
Navigation
Surveying
Measuring instruments
Wood, metal, glass
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 with the Brandis label was 1932.
Black metal frame with wood handle. Maker’s no. 5071, also includes US Navy no. 2696, Navy certificate dated 9/18/1939. On index arm is “Brandis & Sons, Brooklyn” Included 3 black painted telescopes, vernier read with swivel magnifying lens, tangent screw and clamping arms on index arm, and threaded telescope bracket .
Brandis & Sons, Brooklyn, New York
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1939
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory, Urbana, Illinois
Sextant
Astronomy
Navigation
Surveying
Measuring instruments
Wood, metal, glass
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 28012 1943, type no 3052-1-A”.
Bendix Aviation Co., Eclipse-Pioneer division, Teterboro, New Jersey
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1943
Michael Svec
Copyright MIchael Svec
image/jpg
English
physical object
University of Illinois Observatory, Urbana, Illinois