Herman Hollerith’s Tabulating Machine

In 1890, the U.S. Government had a problem. With the nation’s population growing rapidly, hand-counting the results was proving impractical—the 1880 census took a full 7 years to tabulate. Policymakers worried that the 1890 census wouldn’t even be counted by 1900, making reapportionment of congressional seats—as required by the Constitution—impossible.

Enter the Buffalo, New York, native Herman Hollerith. The engineer was pondering this very problem in the early 1880s when, on a train, his eyes fell upon a conductor’s punch card. Hollerith’s work over the next decade eventually led to the groundbreaking invention of the punch card tabulating machine, installed in a federal government office for the very first time on this day in 1888.

“Hollerith had actually worked on the census of 1880, and he was really intrigued by the notion of trying to automate the process,” says Peggy Kidwell, curator of computing history at the American History Museum, which is home to an early version of Hollerith’s device. He began by experimenting with paper rolls that were punched with holes to represent information, but eventually settled on punch cards, which were more durable and could be fed through a counting machine more easily.

Given the capacities of previous devices of the era, Hollerith’s prototype was revolutionary. “What happened is that you took a card, and you had the punch, and you put in a hole whereever there was something that you wanted to enter as information,” Kidwell says. For the census, each card represented an individual, and each hole a point of data—for example, a hole in one location would represent a male, and a hole in a different spot would represent a female.

“On the tabulating machine, there was a contact point where there were little cups of mercury—as many cups as there could be holes in the card,” says Kidwell. “When it pushed the card down, if there was a hole, you made electrical contact, and that made the machine register the piece of information.” A series of dials across the “dashboard” of the device displayed the counts for a number of categories.

Although an operator still had to manually feed the cards through the counter, this was exponentially faster than simply counting census forms by hand. The machine also included a sorter, which could select a particular group of cards based on multiple criteria. “You could find out, for example, all the Norwegian-born people in Minnesota,” Kidwell says. “If you were of Norwegian descent, you would have a hole for that, if you lived in Minnesota, you’d have another hole, so you could pick out and count all of the cards that had both.”

Before the 1890 census, the machine was first tested in several smaller capacities, including the health departments of Baltimore and New York, and the U.S. War Department, which marked the first federal use of the device. “The department’s Records and Health division would use the machine for compiling monthly health statistics on individual soldiers,” says Kidwell. “Each card represented an individual, and each hole position stood for a particular type of information, such as the type of disease, whether it had been contracted in the line of duty, and whether the solider had been admitted to sick report.”

By the time the census rolled around, the tabulating machine was finely tuned and ready to go. Without the inventions, experts had estimated, the 1890 census would have taken 13 years to fully tabulate. With the device in place, the tabulation finished ahead of schedule and under budget.

Although the tabulating machine looks more like an ancient relic than a modern computer, its invention proved to be pivotal in the history of information technology. With the proceeds from leasing his machines to the Census Bureau, Hollerith founded the Tabulating Machine Company in 1896. Eventually, it would merge with several other firms in 1911, and was renamed International Business Machines in 1924.

The company continued to develop faster and more complex tabulating machines over the next several decades. “The scope of what the machines were able to do expanded, and that meant that the company had enough money to invest in the kinds of research that would be needed when you got really expensive machines, like electronic computers,” says Kidwell. You might know the company better by its acronym, still in use today: I.B.M.

Joseph Stromberg | | READ MORE

Joseph Stromberg was previously a digital reporter for Smithsonian.