A Forgotten African American Mathematician: Charles T. Gidiney of Troy, New York

Article excerpt

African American men made considerable contributions to the field of mathematics in the 1700s and 1800s) The earliest African American mathematician is thought to be the slave Thomas Fuller (d. 1790), whose obituary termed him "the famous Africa Calculator" who could, among other feats, "give the number of months, days, weeks, hours, minutes and seconds in any period of time that any person chose to mention, allowing in his calculation for all leap years that happened in the time." (2) Better known is Benjamin Banneker (d. 1806), who taught himself advanced mathematics and astronomical calculations and created a famous almanac featuring astronomical predictions.(3)

In 1849, Charles Reason (d. 1893) became the first African American professor at a predominately white college, namely Central College in McGrawville, Cortland County, New York. He was professor of belles lettres, Greek, Latin, and French, and appointed as an adjunct professor of mathematics.(4) Edward Alexander Bouchet (d. 1918) was the first African American to earn a PhD in the U.S. (in geometrical optics, a branch of physics, from Yale University in 1876).(5) In 1886, Kelly Miller (d. 1939) was the first African American to study mathematics at the graduate level, at Johns Hopkins University.(6) In 1925, the first African American to earn a PhD in pure mathematics, from Cornell University, was Elbert Frank Cox (d. 1969).(7) These men, whether informally or formally educated, are famous for their mathematical achievements. One story that has not been told, however, is that of a lesser known and non-formally educated African American man who also was actively involved in the field of mathematics, Charles T. Gidiney. (8)

On Saturday afternoon, October 20, 1877, the Troy Times reported a mathematical discovery in its local news section, "Home Matters": Charles T. Gidney [sic], a resident of Troy, New York, claimed to have calculated "The True Ratio Between a Diameter and Circumference of a Circle," or pi (11). This article was then reprinted in the October 22, 1877 issue of the New York Times under the title "A Negro Mathematician's Claim":

  The Troy Times of Saturday says: "A colored man named Giciney,
  residing on North Third Street, below Jacob, claims to have
  discovered the true and exact ratio between the diameter and
  circumference of a circle. According to the accepted rule, with
  the diameter or circumference alone given, the other cannot be
  exactly told. The ratio is 3.14159 plus, or as commonly used,
  3.1416 plus. Mr. Gidney claims that by an algebraic calculation
  he has discovered the exact ratio, and he has in preparation a
  book on the subject which he intends shortly to publish. The
  demonstration of this discovery is now receiving the attention
  of competent mathematicians, and whether it amounts to anything
  or not will soon be determined. Mr. Gidney possesses little or
  no education except in mathematics, and in this branch it is
  said he is able to solve most difficult problems." (9)

Notices about this discovery also appeared in several newspapers across the nation. Both the Indianapolis Sentinel of October 24, 1877 (10) and the New Orleans' Weekly Louisianian of November 3, 1877 repeat the Times notice, with an error in the latter claiming that the ratio of pi is "4.14159 plus". (11) The October 29, 1877 Jersey Journal of New Jersey summarizes Gidiney's findings in a section dedicated to humorous and/or unusual news items, quipping that "a Troy publisher is printing a book on the subject. Several lunatics on this subject have already been fed at the State's expense, and the thing is about played out." (12) The March 1, 1879 issue of the Si. Albans Daily Messenger of Vermont focuses on both the poverty and vulnerability of the inventor, claiming that Gidiney, "a poor man, more than sixty years old" is "jealous of his discovery" and thus "is guarding it until he can secure the protection of the law to prevent others from wresting it from him. …