What is a Tabulating Machine?

Tabulating machines made their first appearance in the United States as a valuable tool in helping to provide an accurate count for the national census. Introduced to help order and process data associated with the 1890 national census, the tabulating machine was developed by Herman Hollerith. The purpose of the tabulating machine was to speed up the process of assimilating census data into a usable form that would meet the needs of a country that was experiencing a significant growth in population from one decade to the next.

The need for an improved method of processing data related to the population of the country reached a peak after the 1880 census. Over seven years were required to organize the collected information and produce a relatively reliable report on the status of the country’s population. Estimates on the increase in population between 1880 and 1890 indicated that it would take roughly twice as long to produce results from the next census.

In response to this need for quicker tabulations, Hollerith created a punch card technology that allowed quick and easy coding for state of residence, age, gender, and other information considered to be important. The series of holes punched in the cards represented the collected data. In order to sort and count the data for each component, the cards were fed into the tabulating machine.

The tabulating machine effectively read the data, based on the configuration of the hole punches. The cards ran over a series of pools filled with mercury. Each pool corresponded to a hole in the punch card. Wires were pressed into the cards and followed through to the mercury. This completed a connection of electric current, which in turn would advance a counter for each bit of data.

When the process was complete, a bell would ring and another card could be inserted. Clerks would group the cards based on the information contained on the card, providing a permanent set of documentation for the census. With the assistance of the new tabulating machine, the 1890 census was completed and double-checked for accuracy within eighteen months.

Hollerith’s innovation was found to be helpful with other forms of accounting as well. In 1896, Hollerith founded the Tabulating Machine Company. Within twenty years, this company merged with three others to form the Computing Tabulating Recording Corporation. As the organization grew and diversified, another name change occurred in 1924, when the company became known as IBM.

The basic punch card developed for use with the original tabulating machine continued to be used well into the middle of the 20th century. Punch card technology continued to be a driving force until they were phased out in the early 1980’s and replaced with new computer related technological advances.