Old, Weird Tech: Hollerith 1890 Census Tabulating Machine

Commissioned by the United States Census Bureau to make counting people easier, the device would lead to the creation of IBM

After the United States Census Bureau dispatched its workers across the United States in 1880 to survey all 50 million Americans -- about 19 million more than there were twenty years earlier, before westward expansion -- the census workers got together for the hard part of the job: counting everybody and sorting them into meaningful categories. That took eight years. With another census scheduled to start only two years later, "it was clear to the census takers that their job would become impossible unless there was a great leap forward in tabulating technology," according to a 2007 article on Wired.com.

That article was republished today to mark the 121st anniversary of Herman Hollerith's tabulating machine, the spring-loaded device invented in 1890 just in time for the next Great American Survey.

In anticipation of using Hollerith's machine to tabulate that years' data, census workers in 1890 spread out around the country with special punch cards designed to be the same size as paper currency for ease of transport and storage. Those cards would eventually be fed into the machine, one by one. Hollerith's device used needles to read whether or not certain holes had been punched in the card, with each hole representing a different census category. If a hole was punched, the corresponding needle would make contact with an electric plate underneath the card and advance a particular counter on the machine.

"This apparatus works unerringly as the mills of the gods but beats them hollow as to speed," according to the Electrical Engineer's description of the Hollerith machine in an issue dated November 11, 1891. Improvements on the machine in subsequent years made it capable of basic arithmetic and of automatically feeding punch cards into a reader.

Hollerith stuck with his invention, eventually establishing a company to market the machines. The company would go on to merge with others producing similar products and, twenty years later, IBM was born from Hollerith's efforts.

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Image: Wikimedia Commons.