octant
Date: 1764
Inventory Number: 0007
Classification: Octant
Maker: Benjamin Martin (1704 - 1782)
User: John Winthrop (1714 - 1779)
User: Samuel Williams (1743 - 1817)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
43.7 x 36.3 x 6.2 cm (17 3/16 x 14 5/16 x 2 7/16 in.)
Accessories: small brass scope with brass and ivory holder.
Bibliography:
The Apparatus of Science at Harvard, 1765-1800
Description:
This brass octant is a superbly engraved, precision instrument with elegant, curving cross braces that serve as both handle and structural support for the frame.
The limb is divided from -5° to 95° every 1° and is subdivided every 20'. The vernier on the index arm reads the scale to 1'. There is a front pinhole sight and back pinhole sight. The front one has two holes with a rotating cover. There are two shades, one red and the other darker red. The shades can be moved to another slot for use by the back sight. The half-silvered horizon glass has wingnuts and tightening screws on the back of the frame and fine adjustment screws on the front. The back sight has similar adjustment screws.
There is a small loose brass scope with brass and ivory holder, visible in upper right corner of two B&W photos, still in storage.
The back of the frame has three feet made of knurled knobs.
The limb is divided from -5° to 95° every 1° and is subdivided every 20'. The vernier on the index arm reads the scale to 1'. There is a front pinhole sight and back pinhole sight. The front one has two holes with a rotating cover. There are two shades, one red and the other darker red. The shades can be moved to another slot for use by the back sight. The half-silvered horizon glass has wingnuts and tightening screws on the back of the frame and fine adjustment screws on the front. The back sight has similar adjustment screws.
There is a small loose brass scope with brass and ivory holder, visible in upper right corner of two B&W photos, still in storage.
The back of the frame has three feet made of knurled knobs.
In Collection(s)
SignedB*Martin London
Inscribedon the index arm: The Gift of Ezekiel Goldthwait Esqr. to the Apparatus of Harvard College in Cambridge NE May 1764
Historical AttributesThis octant was given by Ezekiel Goldthwait of Boston to Harvard College in 1764 in order to replace a similar octant given by Goldthwait in August 1760, which had been used by John Winthrop to observe the Transit of Venus in 1761 from Newfoundland. The 1760 octant had been destroyed in the fire of Harvard Hall in 1764. The new octant was described in the bill of lading as "a Hadleys Quadt: 15 Inches Radius in Brass wtih Mahog[an]y Case lin'd." The case has been lost.
Professor Samuel Williams, Winthrop's successor, likely took this octant to Long Island in Penobscot Bay, Maine in October 1780 to observe the 1780 total solar eclipse. (He also took the Sisson astronomical quadrant, 0061, and Ellicott clock, 0070, and two Short telescopes, 0002 and 0053.) The expedition was endorsed by Harvard and the American Academy of Arts and Sciences, and sponsored by the General Court of Massachusetts.
In 1786, Williams was appointed by the General Court of Massachusetts "to make some observations to determine the running of the dividing line between the States of Massachusetts and New York. " For this survey, Williams took the Goldthwait octant as well as the variation compass by Nairne, 0025.
Professor Samuel Williams, Winthrop's successor, likely took this octant to Long Island in Penobscot Bay, Maine in October 1780 to observe the 1780 total solar eclipse. (He also took the Sisson astronomical quadrant, 0061, and Ellicott clock, 0070, and two Short telescopes, 0002 and 0053.) The expedition was endorsed by Harvard and the American Academy of Arts and Sciences, and sponsored by the General Court of Massachusetts.
In 1786, Williams was appointed by the General Court of Massachusetts "to make some observations to determine the running of the dividing line between the States of Massachusetts and New York. " For this survey, Williams took the Goldthwait octant as well as the variation compass by Nairne, 0025.
ProvenanceGift of Ezekiel Goldthwait of Boston to Harvard College in 1764.
Published ReferencesDavid P. Wheatland, The Apparatus of Science at Harvard, 1765-1800 (Cambridge: Harvard University Press, 1968), 42-43