28-inch celestial globe
Date: 1757
Inventory Number: 0071a
Classification: Globe
Dimensions:90 x 94 x 94 cm (35 7/16 x 37 x 37 in.)
globe diam.: 71 cm (27 15/16 in.)
Bibliography:Lost in Learning: The Art of Discovery
The Apparatus of Science at Harvard, 1765-1800
DescriptionThe globe is made of paper gores glued to a sphere made with plaster and papier mâché. The outlines of the constellations were printed in black ink and later shaded in brown wash. Most constellations have their names in Latin, Greek and Arabic.
The sphere itself is pierced by an iron rod which protrudes through the poles. It rotates within a brass meridian circle (twenty-eight inch in diameter, divided in four 90-degree quadrants) and it rides on a brass semicircle underneath. Six cabriole legs, with acanthus carving on knees and hairy paw-and-ball feet, support a circular wooden frame, itself carved in egg and dart pattern. A scale of degrees, the signs of the zodiac, the Julian and Gregorian calendars as well as a foliate border are all found on the horizon circle.
One special feature of this globe is the ecliptic band, which is made of square divisions for precision positioning. This representation of the zodiac was a trademark of Senex, who said it could be used both in astronomy as well as for the determination of the longitude at sea.
Signedin cartouche: Now Made & Sold with Several New Improvements by BENJ: MARTIN only in Fleet Street London 1757
Inscribedin cartouche: The CELESTIAL GLOBE On which the True Face of the Heavens is delineated: & the Constellations containing upwards of 2000 stars more than are on any former Globes, are laid down from the most recent & Accurate Observations of Astronomers and Adjusted to the Year 1740. by Jo.n SENEX F.R.S.
FunctionA celestial globe is a cartographic representation of the heaven. It depicts stars, constellations, and any number of other celestial phenomena. It could also be used to make astronomical calculations, such as the time when a particular star rises above the horizon, or the date of the vernal equinox.
Historical AttributesBenjamin Martin sent a pair of globes to Harvard in 1765 thus described: "a pair of 28 Inch Globes in Mahogany carv'd frames Silver'd & Lacquer'd Meredians &c... £35"
The globes were selected for Harvard with the help of Benjamin Franklin.
Published ReferencesDavid P. Wheatland, The Apparatus of Science at Harvard, 1765-1800 (Cambridge: Harvard University Press, 1968), 63-64.
Eva Koleva Timothy, Lost in Learning: The Art of Discovery (Newburyport, MA: Athenaeum Publishing, 2010).
This instrument was studied by a group of students for the course Sophomore Tutorial (Spring 2012), Department of the History of Science, Prof. Anne Harrington.
The result of their week-long investigation for this object can be seen on the following website.
The Software used is courtesy of VoiceThread.