Mathematical Objects Relating to Charter Members of the MAA Computing Devices - L. Leland Locke

Leland L. Locke, Gift of Grove City College
Leland L. Locke, Gift of Grove City College, Smithsonian Image DOR2015-00206

Leslie Leland Locke (1875-1943) attended high school, college and graduate school in his home town of Grove City, Pennsylvania, and taught briefly in local schools. He took a position at Michigan State University for a short time before moving on to Adelphi College in Brooklyn. There he continued his studies, working with David Eugene Smith of Columbia University. Locke also played a role in the early years of the College Entrance Examination Board, collecting examples of the then-novel test and serving as a reader for examinations in mathematics. From 1908 to 1933 he was an assistant at the Brooklyn Training School for Teachers, from 1917 to 1939 he was affiliated with Brooklyn College, and from 1932 until his retirement in 1942 was at Brooklyn Technical High School.

Locke took great interest in the history of the quipu, a set of knotted strings used by the Inca of Peru for recordkeeping (the Inca had no written language). Quipus date to roughly the time of the Spanish conquest of Peru in the 16th century. Drawing on collections of the American Museum of Natural History, Locke developed a pioneering interpretation of the quipu. He expanded this into a general survey of about fifty surviving examples, published as The Ancient Quipu or Peruvian Knot Record (1923).

Locke also was intrigued by the history of a much more recent computing device, the calculating machine. In the mid-1800s, machines that could add, subtract, and, with a bit of assistance, multiply became available commercially. By Locke’s time, they were quite common among American actuaries, astronomers, and government officials. Locke not only wrote about early American calculating machines but actively collected them. He initially gave his collection to the Museums of the Peaceful Arts in New York but, when that institution failed, donated it to the Smithsonian, where it remains today.