Horizontal Sundial

This sundial was made by Christopher Colles (1738?-1816), an Irish immigrant surveyor and inventor. Colles has received credit for the first American steam engine, publication in 1789 of the first American road atlas, the country’s first semaphore telegraph system in 1813 and his visionary proposals for canals and waterways. Colles established a scientific instrument business in New York in the mid-1780s, and this sundial was one of his products.
This dial, mounted horizontally, shows the hours at a fixed location, in contrast to a portable pocket dial a traveler might carry from place to place. The copper octagonal plate is pierced by eight holes for fastening it to a base and four more holes for attaching the gnomon (not original), the slanted part of the dial that casts the shadow. The plate is engraved, from the center to the edges, as follows: “C. Colles/fecit/42 Pearl”; a central compass rose; indications of latitude, longitude, noon and midnight: “Lat 40o, 40’”, “Lon 74o W of London” and “N is Noon”/“M is Midnight”; a table showing the equation of time for setting mechanical clocks; the corresponding time at major world cities at noon or midnight in New York; Chapter ring with Arabic hour numerals and marks for half hours and minutes; and a Latin inscription, sometimes found on other sundials, that reads “Me ortum vides forsan non occasum” (“You see me [the sun] rise, but perhaps you shall not see me set”).
Other sundials by Colles survive in museum collections at the New-York Historical Society and Van Cortlandt Manor, Historic Hudson Valley. An oil portrait of Colles by James Frothingham is in the Metropolitan Museum of Art, New York.
See also: Bathe, Greville. An Engineer’s Miscellany. Philadelphia: Patterson and White, 1938.
Colles, Christopher. A Survey of the Roads of the United States of America, 1789. Edited by Walter W. Ristow. Cambridge, Mass.: Belknap of Harvard University Press, 1961.
Koeppel, Gerard. Water for Gotham: A History. Princeton: Princeton University Press, 2000.
Popper, Deborah Epstein. “Poor Christopher Colles: An Innovator’s Obstacles in Early America.” The Journal of American Culture, 28(June 2005): 178-190.
Currently not on view
Object Name
date made
after 1773
Colles, Christopher
Physical Description
brass (overall material)
copper (overall material)
wood (overall material)
overall: 14 3/8 in x 11 1/2 in x 11 1/2 in; 36.5125 cm x 29.21 cm x 29.21 cm
overall: 14 3/8 in x 11 3/8 in; 36.5125 cm x 28.8925 cm
place made
United States: New York, New York
ID Number
catalog number
accession number
Measuring & Mapping
See more items in
Work and Industry: Mechanisms
Data Source
National Museum of American History, Kenneth E. Behring Center

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