triangular engineer's scale
Datecirca 1936
Inventory Number1997-1-1922
ClassificationRuler
Subject
Maker
Keuffel & Esser Company
1867 - 1987
User
William R. Osgood
Cultural Region
Place of Origin
Dimensionsscale: 2 × 2.2 × 31.8 cm (13/16 × 7/8 × 12 1/2 in.)
case: 2.8 × 2.8 × 32.7 cm (1 1/8 × 1 1/8 × 12 7/8 in.)
case: 2.8 × 2.8 × 32.7 cm (1 1/8 × 1 1/8 × 12 7/8 in.)
Material
Accessoriestriangular cardboard sleeve case
DescriptionThe triangle ruler is stored in a triangular cardboard sleeve case with black covering. The rule is made of a single piece of solid boxwood. The center bar axis of the ruler is constituted of a concave depression the length of each side. Each of the three sides has two sets of plane measurements in black lettering, one on either side of the central depression.
Signedinscribed in triangular ends: W.R.O.
in black lettering along center bar: KEUFFEL & ESSER Co.
Inscribedin blacklettering along center bar: US ST'D / 1631 / N.Y.
underneath initials on one triangular end: 10
FunctionTriangle rulers are used for measuring and drawing straight lines in various plane scales. They are particularly useful for engineers, architects, and draftsmen for providing numerous measures at once. Blueprints, and other design schematics are not drawn to scale and these rulers make it easy to determine the actual length of represented lines with minimal calculations.
ProvenanceRuler was owned by William R. Osgood (Engineer, Harvard class of 1917). The ruler was donated by his nephew Theodore K. Osgood on November 20, 1997.
Keuffel & Esser Company
Date: circa 1936
Accessories: triangular cardboard sleeve case
Object number: 1997-1-1923
Keuffel & Esser Company
Date: circa 1936
Accessories: triangular cardboard sleeve case
Object number: 1997-1-1921
American
Date: circa 1935
Accessories: triangular cardboard sleeve case
Object number: 1997-1-1924
Darling, Brown, and Sharpe
Date: circa 1890
Accessories: fitted, triangular leather holder
Object number: DW0467
Eugene Dietzgen Company
Date: circa 1925
Accessories: triangular cardboard sleeve case
Object number: 1997-1-1920
Keuffel & Esser Company
Date: circa 1935
Accessories: leather sleeve case
Object number: 1997-1-1928
Keuffel & Esser Company
Date: circa 1954
Accessories: mahogany case
Object number: 1997-1-1997
Keuffel & Esser Company
Date: early 20th Century
Object number: 2003-1-0215
Charles W. Dixey
Date: circa 1830
Accessories: silver framed green shagreen case
original curatorial cards and photos
Object number: DW0288
Frederick Post Company
Date: early 20th Century
Object number: 2004-1-0340