Keuffel & Esser 4220 Amsler Style Polar Planimeter

Description
This tarnished German silver instrument has two arms pivoted at one end. One arm has a tracer point and index marks for four ratios: 1 square D. (centimeters or meters, perhaps), 15 square inches, 10 square inches, and 10 square chains. A screw assembly adjusts the length of the tracer arm. A support for the tracer point prevents it from tearing the paper. Two numbers are stamped underneath the arm: 31, which appears to overstamp the number 33, and 690.
The other arm is jointed. A cylindrical weight may be placed in the end of that arm. Underneath the weight is marked: 35. The jointed part of the arm is marked: KEUFFEL & ESSER Co N.Y. Underneath the arm is stamped: 31. A carriage at the pivot holds a white plastic measuring wheel with vernier and a horizontal metal registering dial.
A mahogany case has dark blue velvet lining the supports. A leather pouch holds the weight. A paper chart for adjusting the tracer arm is held in the lid by black plastic edges and brass screws. The columns are labeled: Proportion, Adjustement [sic] on tracer-arm, and Value of unit of the Vernier. "Sq. units" is handwritten above the first entry in the Proportion column (1:1,000). The vernier entry for proportion 1:4,000 has been changed from 100 to 160 square meters.
Keuffel & Esser sold this planimeter as model 1102 from 1892 to 1901 and as model 4220 from 1901 to 1936. It sold for $28.00 in 1909 and for $45.50 in 1936. The serial number, 690, and lack of rectangular support for the joint in the weighted arm suggest that this example was made later than 1981.0348.01. Wesleyan University donated this planimeter to the Museum in 1984–1985 with a large collection of plaster and string mathematical models purchased in 1895 from the Darmstadt, Germany, firm of L. Brill.
References: Catalogue of Keuffel & Esser, 33rd ed. (New York, 1909), 319; Catalogue of Keuffel & Esser, 38th ed. (New York, 1936), 336; Clark McCoy, "Collection of Pages from K&E Catalogs for the 4220 Family of Polar Planimeters," http://www.mccoys-kecatalogs.com/PlanimeterModels/ke4220family.htm.
Location
Currently not on view
Object Name
planimeter
date made
1901-1936
distributor
Keuffel & Esser Co.
maker
Keuffel & Esser Co.
Physical Description
metal (overall material)
ivory or celluloid (overall material)
mahogany (overall material)
german silver (overall material)
Measurements
case: 6.5 cm x 26 cm x 8 cm; 2 9/16 in x 10 1/4 in x 3 5/32 in
place made
United States: New York, New York
place distributed
United States: New York, New York
ID Number
1985.0112.218
catalog number
1985.0112.218
accession number
1985.0112
subject
Science & Mathematics
Mathematics
Engineering
Planimeters
See more items in
Medicine and Science: Mathematics
Planimeters
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Wesleyan University
Additional Media

Visitor Comments

Add a comment about this object

Submit a comment or ask a question about this object using the form below. Submissions are moderated and may receive a curator response. Please note that we cannot evaluate or appraise your personal artifacts. For other questions or general inquiries please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Image CAPTCHA
Enter the characters shown in the image.