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French Curve or Irregular Curve, Keuffel & Esser 1860, #21

French Curve or Irregular Curve, Keuffel & Esser 1860, #21

Usage conditions apply
This flat plastic (xylonite) transparent curve has two openings with curved edges as well as curves around the outer edges. It also has two small circular holes. A mark stamped on one side reads: Keuffel&Esser CO [/] NY. A mark adjacent to this reads: 1860 (/) 21. A mark scratched on the other side gives the owner’s name: IKE MOLELLA. Another mark on this side reads: IM.
Keuffel & Esser offered Irregular or French curves in transparent xylonite as model 1860 from at least 1909 until at least 1949. From at least 1890 until 1909 had offered them in hard rubber as model 1810 or 1820.
Engineer Isaac G. Mollela, the former owner of this curve, obtained his A.B. from Cornell University in 1935 (he also was associated with the class of 1932). He fought in the U.S. armed forces during World War II and then spent most of his career with General Electric.
Accession File.
Keuffel & Esser Company, Catalog, New York, 1890, p. 136. Hard rubber only.
Keuffel & Esser Company, Catalog, New York, 1892, p. 136. Hard rubber only.
Keuffel & Esser Company, Catalog, New York, 1909, p. 203, 210. Both xylonite and hard rubber.
Keuffel & Esser Company, Catalog, New York, 1921, pp. 148-149. Xylonite only.
Keuffel & Esser Company, Catalog, New York, 1936, pp. 232-233.
Keuffel & Esser, Drafting and Reproduction Catalog, New York, 1949, pp. 169-170.
Currently not on view
Object Name
date made
Keuffel & Esser Co.
Physical Description
plastic (overall material)
overall:.1 cm x 18.7 cm x 7.7 cm; 1/32 in x 7 3/8 in x 3 1/32 in
ID Number
accession number
catalog number
Credit Line
In Memory of Isaac Giacinto Molella
Drawing Instruments
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History
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