Herman Hollerith

From Citizendium, the Citizens' Compendium
Jump to: navigation, search
This article is developing and not approved.
Main Article
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
This editable Main Article is under development and not meant to be cited; by editing it you can help to improve it towards a future approved, citable version. These unapproved articles are subject to a disclaimer.

Herman Hollerith was an American engineer and businessman important in the history of computing for having invented punched card input for program instructions and developed the tabulating company that became International Business Machines.[1]

Hollerith was born on February 29, 1860 in Buffalo, New York. In 1875, Hollerith attended the City College of New York, he graduated from the Columbia School of Mines in 1879 with an engineering degree.[2] After graduating, Hollerith took up work with the United States Census Bureau, and was appointed Chief Special Agent. Hollerith's contribution to computing was inspired by his work at the USCB, especially from Dr. John Shaw Billings who suggested that there should be a way to process the large amount of census data by some mechanical means and pointed out that all nominal information (such as state of birth) could be coded into numbers. Hollerith later recalled, "I was traveling in the West and I had a ticket with what I think was called a punch photograph. The conductor punched out a description of the individual, as light hair, dark eyes, large nose, etc. So you see, I only made a punch photograph of each person."[3]

In 1884, Hollerith invented a mechanical way to rapidly tabulate census information. He recognized that cards could be used as storage medium for census data once the information was turned into numbers that could be punched on a card. His experiments lad to a process by where a pin would go through a hole in the card to complete an electrical circuit. In 1889, the Census Bureau staged a competition; the three competitors had to process the 10,491 returns of the 1880 population census for St. Louis by recording of the returns onto the cards or paper slips and then tabulating the results into statistical tables. At the first step the Hollerith system was no faster than the competing manual systems. But in the tabulation phase it came into its own, proving up to ten times as fast; furthermore, many other tabulations became possible once the deck of cards was ready. The commission was unanimous in recommending that the Hollerith Electric Tabulating System be adopted for the 1890 census. Hollerith's system by which cards could be read and tabulated on a mechanical counter through a circuit completion was called the Hollerith Electric Tabulating System. It read cards one by one, using a "press" of 288 retractable spring-loaded pins. When the press was lowered onto the card, pins that dropped through the holes dipped into a mercury cup, and completed an electrical circuit, which added one to one of forty counters on the front of the machine. By 1890, the machines were improved so that a simple keyboard could be used to punch the cards. As a Census official he subcontracted with Western Electric to build 700 card punches and several hundred tabulators, and negotiated with paper manufacturers to supply the 60 million-plus manila cards needed. He trained 2000 clerks in Washington to use the system; they punched 100 cards a minute, while 80 other clerks ran tabulators that counted a thousand cards an hour. The process produced tables much faster than the 1880 census.[4]

By 1891 the Norwegians adopted the system for their census, followed by Russia, Britain and Canada. Hollerith started his own business in 1896 that provided machines and cards to census bureaus around the world, and to insurance companies. He founded the Tabulating Machine Company, a predecessor to the International Business Machines Corporation.


  • Austrian, Geoffrey. Herman Hollerith, forgotten giant of information processing Columbia University Press, 1982.


  1. Douglas W. Jones. Punched Cards: A brief illustrated technical history. University of Iowa Punched Card Collection. Retrieved on 2009-02-22. mirror
  2. O'Connor, J. J. and Robertson, E. F. (July 1999). Hollerith Biography. School of Mathematics and Statistics University of St. Andrews, Scotland. Retrieved on 2007-05-14.
  3. William Aspray and Martin Campbell-Kelly Computer: A History of the Information Machine. (1996) p. 22.
  4. Aspray and Campbell-Kelly, p. 23-25. The original punch cards were destroyed after use, A later fire destroyed the original manuscript census returns for 1890.