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Consul the Educated Monkey, or the inventions of William H. Robertson

Educator Richard Lodish has just given the museum an example of a computing device called Consul the Educated Monkey. This is one of the first mathematical instruments named for a movie character, and one of few associated with a vaudeville act. The history of the educational toy also suggests the role of Dayton, Ohio, as a place of American invention.

Flat math helper with numbers, monkey, long limbs

As the image suggests, Consul the Educated Monkey is a metal linkage superimposed on a square metal sheet that has a multiplication table printed on it. Placing the feet of the monkey at two numbers listed along the base of the sheet, the linkage moves so that the product appears between the hands of the monkey. In the image, the feet are at about 3 and 10, and the product is (roughly) 30.

As Caitlin Wylie of the New Jersey Institute of Technology has found, a performing monkey named Consul, trained in Britain, came to the United States in 1909. Apparently he was not the first trained monkey to be given the name Consul, but seems to have been the best publicized. He performed in vaudeville shows across the country. Records in the National Cash Register (NCR) Company Collection at Dayton History indicate that the monkey visited Dayton and NCR on September 23, 1910. A surviving photograph there shows him toying with a cash register. Moreover, a short film entitled "Consul Crosses the Atlantic," released in 1909, described Consul's visit to the United States. The movie was showing in Chicago as late as 1915.

Also in 1915, William Henry Robertson, a draftsman at NCR, applied for two patents. The first, for "a calculating device," was for "a quick and simple method of finding results" on a chart. The second was for a toy using the same mechanism "to stimulate the interest of children in the study of numbers." In this second patent, the linkage took the form of a monkey. Robertson assigned both of his patents to the Educational Novelty Company of Dayton, which soon was selling Consul.

Black and white line drawing of monkey educational toy with signatures and patent information

A 1915 notice in Walden’s Stationer and Printer mentions the incorporation of the Educational Novelty Company by Robertson, F. L. Fuller, and W. H. Fryer. The Dayton city directory for that year listed Fred L. Fuller as an inventor at NCR and William H. Fryer as the supervisor of the engineering division there. It also lists the Educational Novelty Company, with Robertson as president, Fuller as vice-president and treasurer, and another NCR employee, chemist and engineer of tests Frank O. Clements, as secretary. Educational Novelty Company appeared again in the 1916 city directory, this time with Robertson as president and Fuller as both treasurer and secretary. By 1917, the company disappeared. Manufacture of Consul the Educated Monkey soon shifted to Massachusetts, and the example shown was probably made in that state.

Who was the inventor William Henry Robertson? Government records, city directories, and college catalogs provide tidbits. Born on a Texas farm in September of 1877, he attended Weatherford College and then the University of Texas at Austin. In 1901, he accepted a position teaching mathematics at the high school in Waxahachie, Texas. Over the next few years, Robertson turned his eyes northward. He apparently wasn't working at NCR when Consul visited, but arrived the next year—perhaps soon enough to hear stories!

Robertson and his colleagues didn't make great profits from Consul. However, the inventor's career at NCR flourished. He was promoted to the rank of designer in 1915 and inventor in 1921. U.S. Patent Office records list cash register patents he took out and assigned to NCR that were applied for as early as 1923 and as late as 1943. He apparently left the company in the 1940s, working for a time in another industry for which Dayton is known, aeronautics. While at Globe Industries, Inc., he took out a patent for gearing for aeronautical apparatus and another for a control mechanism for camera shutters. In retirement, he moved to Michigan, living there until his death in 1973 at the ripe age of ninety-six.

Consul the Educated Monkey did not transform American mathematical practice or teaching. William Henry Robertson does not rank among the foremost American inventors of his time. Nonetheless, the story of this small object and its inventor suggest some of the intimate connections between American education, invention, business, geography, and popular culture a century ago.

Peggy Aldrich Kidwell is curator of mathematics. To learn more, see: Kelley Swain, editor, The Rules of Form: Sonnets and Slide Rules, Cambridge, England: Whipple Museum of the History of Science, 2012.

To learn more about Consul, see: Kelley Swain, editor, The Rules of Form: Sonnets and Slide Rules, Cambridge, England: Whipple Museum of the History of Science, 2012. You can also learn more about the arithmetic teaching devices and cash and credit registers in our collection.

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