According to a note that came with this item: “This is one of two 'Grains' that composed a KBr cylindric boule 5" long and 5" in diameter that John Strong (1905-1992) grew in 1929, when he was a graduate student under Professor Harrison Randall at the University of Michigan. The KBr prism of the first recording infrared spectrometer was made from a subsequent successful boule. This single crystal, grown under reducing conditions, is notable in being free of cloudiness throughout. John Strong." John Donovan Strong (1905-1992) was a noted American astronomer and optical scientist.
Boxed set of ten tuning forks. Each fork is provided with weights, and identified by tone, number, and the Rudolph Koenig insignia. This set came from the U.S. Military Academy at West Point.
This prism spectrometer was made by Franz Schmidt & Haensch, of Berlin, and purchased from Alfred Hirschmann, for the Ryerson Laboratory at the University of Chicago, on Jan. 1, 1894. The cost was $112.50. The inked “R.L. 194” inscription refers to the Ryerson Laboratory.
Alfred Hirschmann was at the Columbian Exposition, in Chicago in 1893, representing Franz Schmidt & Haensch, and the Physikalish Technische Reichsanstalt in Berlin. He was in charge of the German instrument exhibit.
Ref: The World’s Columbian Exposition, Chicago, 1893. Special Catalogue of the Collective Exhibition of Scientific Instruments and Appliances exhibited by the Deutsche Gesellschaft fur Mechanik und Optik (Berlin, 1893), pp. 19-22.
This spectroscope was designed to be used with a telescope to study the light of the sun. It was made in Dublin in 1877 by the famous instrument maker Howard Grubb (1844–1931). It was used with the 9 ½ inch Alvan Clark & Sons refractor at Princeton University.
When the College of New Jersey at Princeton hired the astronomer Charles A. Young in 1877, they also gave him funds to equip the new John C. Green student observatory. One of his first purchases was this instrument. It was custom-made, and Young helped refine the design. (Grubb's company later advertised that this was the first such spectroscope that they had sold.) The most unusual feature of this instrument is the use of a complicated system of multiple prisms to disperse the light and produce a highly detailed view of the solar spectrum.
In use, the spectroscope was mounted at the eyepiece end of the telescope and light from the sun would be directed through it. As the light passed from one prism into the next, it would be increasing dispersed, or spread out. To make the instrument more compact, the beam of light was directed first through the upper portion of the prisms and then back through the bottom part. Depending on how it was configured, the light could thus be passed through either 2, 4, 6 or 8 prisms. A particular area of the solar spectrum could be viewed by turning a small chain that moved each prism by the same amount. Because of the large number of optical surfaces involved, the light loss in this instrument was almost certainly in the 90 percent range. This was an advantage when viewing the Sun, but it reduced the usefulness of this instrument for other purposes, such as measuring the spectra of stars. The success of this instrument in making precise measurements of the solar spectrum (and thus revealing information about the composition of the sun and its atmosphere) led to its wider adoption as an important astronomical tool.
With a Lissajous apparatus—devised by Jules Antoine Lissajous (1822-1880), a French mathematician—a beam of light is bounced off a mirror attached to a horizontal tuning fork, then off a second mirror attached to a vertical tuning fork, and then onto a wall. The resulting images are the graphs of complex harmonic motions known as Lissajous figures. This example came from the Smithsonian Institution Instrument Room. The "RK" inscription is that of Rudolph Koenig in Paris.
Patent model for Eli Thayer, "Improvement in Plane Angulometers," U.S. Patent 36,312 (Aug. 26, 1862). Eli Thayer (1819-1899) graduated from Brown University; organized the Oread Institute, a school for young women in Worcester, Mass.; established the Emigrant Aid Society; and served briefly as a member of the House of Representatives.
This is an example of instrument makers feeling their way towards a good design, but not quite getting it right. It is marked "Phelps & Gurley" and "Troy, N.Y." and dates from the period 1845-1851 when Jonas Phelps and William Gurley were in business together. Several elements of its design originated with Oscar Hanks, the mathematical instrument maker with whom Phelps and Gurley both apprenticed. W. & L. E. Gurley made a similar instrument that they called a Vernier Transit Compass.
The variation arc at the south side of the compass extends 20 degrees either way; the vernier reads to 2 minutes. There are level vials at North and West. The small vertical circle is read by vernier to 10 minutes.
William H. Skerritt, Catalog of the Charles E. Smart Collection of Antique Surveying Instruments (Troy, N.Y., 1996), p. 29.
Boxed set of ten tuning forks. Each fork is provided with weights, and identified by tone, number, and the Rudolph Koenig insignia. The set came from the U.S. Military Academy at West Point.
This pen point is part of the set of drawing instruments owned and used by Samuel Pierpont Langley, the astrophysicist who served as the third Secretary of the Smithsonian Institution.
With a Lissajous apparatus—devised by Jules Antoine Lissajous (1822-1880), a French mathematician—a beam of light is bounced off a mirror attached to a horizontal tuning fork, then off a second mirror attached to a vertical tuning fork, and then onto a wall. The resulting images are the graphs of complex harmonic motions known as Lissajous figures. This example came from the Smithsonian Institution Instrument Room. The "RK" inscription is that of Rudolph Koenig in Paris.