# Judah Levin

At the beginning of the 20th century Judah Levin (1863-1926), an Orthodox rabbi from Detroit, Michigan, devised three calculating machines, which he patented from 1902 until 1906. A working model only of the third calculator of Levin survived to our time, and it is kept in the collection of the National Museum of American History, Washington, D.C. (see the image below).

First (US patent No. 706000 from 1902) and second (US patent No. 727392 from 1903) calculator of Levin are simple adders, with a similar internal mechanism, but with different input mechanism (the first one is using turning handles, while the second is using rotating wheels similarly to Pascaline). The third calculator of Levin (US patent No. 815542, Great Britain patent No. 190606717, French patent No. 364433, Canadian patent No. 106810) is a more complex ten-key non-printing manually operated adding machine, which deserves our attention because (although it was not put in serial production), it looks like a well designed and robust device.

The machine is stored in a small black suitcase covered with leather, lined with cloth, and provided with a metal handle on top. It is a steel (for the frame), plastic and paper (for keys), leather and velvet (for the suitcase) made device, with overall measurements: 25 cm x 39.5 cm x 15.4 cm.

The ten-digit keys are arranged in two columns (on the patent drawing they are arranged in one column) on the left side of the device. Two rows of nine operating keys across the top indicate the place number of the digit entered. The front row is for addition and the other is for subtraction operations. To enter a number, both the digit key and the place key should be depressed.

By providing two sets of keys, one for determining the digits and the other for determining the value of each digit or its place in the number and also to operate the mechanism, the speed of operation is greatly increased and liability of mistakes lessened, as the keys are operated in the same order in which the person would call or write the number. Thus writing or speaking “4000” the digit “4” is expressed first and its value or place in the number.

Numbers through 9999999 can be indicated. The metal keys have plastic and paper key tops. The space under the keyboard is covered with green velvet. The result is indicated on a row of red number wheels below these two rows of keys.

#### Biography of Judah Levin

Judah (Yehuda) Leib (Leyb) Levin was born Judah Leyb Yoke on 6 April 1862, in Traby, Vilna Province, Russian Empire (now a small town in Belarus—Трабы, Ивьевский район, Гродненская область). Levin’s father was Rabbi Nahum Pinchas, who had a rabbinical degree, but did not accept a pulpit; instead, he conducted business as a landowner in Traby. Judah lost his father when he was eight years old, soon afterward died his mother, and his uncle rabbi Abraham Abramowitz, an esteemed Talmud scholar, assumed the responsibility of raising him. When Judah was 19, he went to study Talmud in Volozhin and Kovno and received rabbinical ordination.

Shortly after his marriage in 1882 to the daughter of a rabbi from Traby—Esther Rhoda Trauber-Levin (1863-1933), Judah Levin, at age 23, became rabbi at Liškiava, Suwalki Province, now a village in Lithuania. The family had four sons: Nathan P., Samuel M. (1888-1975), Isadore (born 1894), and Abraham J. (born 1897).

Levin first immigrated to the eastern United States in 1887, alone, while his family stayed in Russia. In 1888 Levin became the rabbi of Rochester, New York. Two years later he returned to Russia to serve as a rabbi in Kreva (now in Belarus). He left Russia for good in 1892 and found a position in New Haven, Connecticut. The rest of his family joined him a year later. In 1897, Levin accepted an appointment as Chief Rabbi of the United (Orthodox) Jewish Congregations of Detroit, a position he held for the rest of his life. Levin was an ardent supporter of religious Zionism, and he helped support the needs of the Jewish community during a period when it was experiencing tremendous growth. Though not a prolific writer, he published two volumes of sermons and commentary.

Judah Levin died in Detroit on 27 March 1926, at the age of 63, leaving many unpublished manuscripts.