4-foot Gregorian reflecting telescope
Date: circa 1767
Inventory Number: 0001a
Classification: Telescope
Subject:
Maker: James Short (1710 - 1768)
Maker: Thomas Short (1711 - 1788)
Supplier: Benjamin Franklin (1706 - 1790)
User: John Winthrop (1714 - 1779)
Repaired by: W. & S. Jones (fl. 1791 - 1859)
Cultural Region:
Place of Origin:
Dimensions:
172.5 x 150 x 113 cm (67 15/16 x 59 1/16 x 44 1/2 in.)
Material:
Accessories: tin box with spare secondary mirror (0001b); spare eyepiece (0001c); primary mirror in wooden case (0001d)
Bibliography:
The Apparatus of Science at Harvard, 1765-1800
Description:
This large brass Gregorian reflector has a 4-foot focal length and an aperture of 7 1/2 inches. The barrel is 5 feet long. A finder scope is attached. The barrel is fork-mounted in a very elegant manner, with stabilizing braces. The focusing screw is very long, extending almost the entire barrel length.
The mahogany tripod and current altazimuth mounting were provided by William and Samuel Jones in 1817. The vertical arc is divided [115°]-100°-0°-40° every 30', with a vernier reading to 1' of arc. The azimuth circle is divided 0°-360° every 1°, with a vernier reading to 3'. The azimuth circle is also marked with hours in Roman numerals I-XII twice with the vernier reading to 3 minutes. As this sort of marking is customary for right ascension, the mount may have been made from parts used by W. & S. Jones for equatorially-mounted instruments.
There is a dust cover for both the main tube and the finder scope. The tripod has a brass stretcher.
The mahogany tripod and current altazimuth mounting were provided by William and Samuel Jones in 1817. The vertical arc is divided [115°]-100°-0°-40° every 30', with a vernier reading to 1' of arc. The azimuth circle is divided 0°-360° every 1°, with a vernier reading to 3'. The azimuth circle is also marked with hours in Roman numerals I-XII twice with the vernier reading to 3 minutes. As this sort of marking is customary for right ascension, the mount may have been made from parts used by W. & S. Jones for equatorially-mounted instruments.
There is a dust cover for both the main tube and the finder scope. The tripod has a brass stretcher.
In Collection(s)
Signedon tailpiece: JAMES SHORT LONDON 9=48
on tailpiece [engraved inside a scroll]: 1817/ REMOUNTED BY / W & S, JONES, / No. 30 Holborn, / London
on tailpiece [engraved inside a scroll]: 1817/ REMOUNTED BY / W & S, JONES, / No. 30 Holborn, / London
Historical AttributesThis large brass Gregorian telescope has a four-foot focus. The end of the barrel is engraved 9 = 48, indicating that it was only the ninth telescope with this focal length made by James Short, who died before the mirror could be mounted.
The telescope was acquired with the help of Benjamin Franklin, who visited Short's workshop to supervise the progress of the construction. Franklin told Winthrop by letter (2 July 1767) that Short had "finished the material parts that required his own hand" before he died, but the telescope needed "something about the mounting, that was to have been done by another workman." Thomas Short, James's brother, saw to the completion of the instrument. The bill for the remarkable instrument was 100 guineas.
Winthrop kept this telescope at his house, and used it for the Transit of Venus in 1769.
Repairs were necessary by the early 19th century, and these were undertaken in London by W. & S. Jones. They left the primary mirror untouched, explaining that "the figure is very good like all of James Short's." They did supply "a new stand upon an improved principle in brass, with mahogany folding legs, graduated circle and arch, etc., etc.; cleaning and repairing the brass work of the tube, finder, eye piece, etc.; new japaning the tube, cleaning and adjusting speculums of a Short's 5 [sic] feet Reflector 7 inches aperture, with deal case for eye pieces and speculums." They charged £54.12.0.
The College protested. So, on 19 August 1817, William Jones made this case: "Short's telescope was charged originally [at] more than 100 guineas, [yet] his stand was unmechanical or ill contrived....[The new stand] is very material and [a] most expensive part of the instrument, and we are confident in declaring the value of the Telescope at present is 150 pounds, whereas in the state sent to us for practical & steady use, an Astronomer would not have given 50 shillings. The price of our 4 feet, so mounted is 100 guineas."
The telescope was acquired with the help of Benjamin Franklin, who visited Short's workshop to supervise the progress of the construction. Franklin told Winthrop by letter (2 July 1767) that Short had "finished the material parts that required his own hand" before he died, but the telescope needed "something about the mounting, that was to have been done by another workman." Thomas Short, James's brother, saw to the completion of the instrument. The bill for the remarkable instrument was 100 guineas.
Winthrop kept this telescope at his house, and used it for the Transit of Venus in 1769.
Repairs were necessary by the early 19th century, and these were undertaken in London by W. & S. Jones. They left the primary mirror untouched, explaining that "the figure is very good like all of James Short's." They did supply "a new stand upon an improved principle in brass, with mahogany folding legs, graduated circle and arch, etc., etc.; cleaning and repairing the brass work of the tube, finder, eye piece, etc.; new japaning the tube, cleaning and adjusting speculums of a Short's 5 [sic] feet Reflector 7 inches aperture, with deal case for eye pieces and speculums." They charged £54.12.0.
The College protested. So, on 19 August 1817, William Jones made this case: "Short's telescope was charged originally [at] more than 100 guineas, [yet] his stand was unmechanical or ill contrived....[The new stand] is very material and [a] most expensive part of the instrument, and we are confident in declaring the value of the Telescope at present is 150 pounds, whereas in the state sent to us for practical & steady use, an Astronomer would not have given 50 shillings. The price of our 4 feet, so mounted is 100 guineas."
Published ReferencesDavid P. Wheatland, The Apparatus of Science at Harvard, 1765-1800 (Cambridge: Harvard University Press, 1968), 17-19.
Rolf Willach, "List of Extant Reflecting Telescopes Made by James Short," i>Journal of the Antique Telescope Society, no. 29 (Fall 2007): 11-22, no. 186.
