The Constitution of the United States requires that a population count be taken at the beginning of each decade.
This census has always been charged with political significance and continues to be so. It is clear from controversies ahead of the 2020 census.
But less is known how important the census was to the development of the American computer industry, a story I tell in my book, Republic of Numbers: Unexpected Stories of American Mathematicians Throughout History. This history includes the creation of the first automated data processing company, the Tabulation company, 125 years ago, on December 3, 1896.
The only use of the census clearly specified in the Constitution is to allocate seats in the House of Representatives. The most populous states get more seats.
A minimalist interpretation of the census mission would require reporting only the aggregate population of each state. But the census was never limited to that.
A complicating factor arose early on, with the constitutional distinction between “free persons” and “three-fifths of all other people. “It was the infamous shabby compromise of the Founding Fathers between states with large numbers of enslaved people and states where relatively few lived.
The first census, in 1790, also made unconstitutionally mandated distinctions by age and sex. Over the following decades, many other personal attributes were also probed: professional status, marital status, level of education, place of birth, etc.
As the country grew, each census required more effort than the last, not only to collect the data but also to compile it into a usable form. Processing of the 1880 census was not completed until 1888.
It had become a rarely seen, boring, error-prone office exercise.
Since the population clearly continued to grow at a rapid rate, those with the imagination enough could foresee that the processing of the 1890 census would indeed be horrible without a change of procedure.
A new invention
John Shaw Billings, a physician assigned to help the census bureau compile health statistics, had observed closely the immense tabulation efforts required to process the raw data for 1880. He expressed his concerns to a young engineer in mechanical census assistant, Herman Hollerith, a recent graduate of the Columbia School of Mines.
On September 23, 1884, the United States Patent Office registered a submission from Hollerith, 24, entitled “The art of compiling statistics. “
By gradually improving the ideas of this initial submission, Hollerith would decisively win an 1889 competition to improve processing of the 1890 census.
the technological solutions designed by Hollerith involved a series of mechanical and electrical devices. The first crucial innovation was to translate the data from the handwritten census tally sheets into patterns of holes punched in the cards. As Hollerith put it, in the 1889 revision of his patent application, “A hole is thus drilled corresponding to the person, and then a hole according to whether the person is male or female, another record as it is. native or foreign, another either white or colored, & c.
This process required the development of special machines to ensure that the holes could be drilled with precision and efficiency.
Hollerith then designed a machine to “read” the card, probing the card with pins, so that only where there was a hole that the pin would pass through the card to make an electrical connection, causing the appropriate counter to advance.
For example, if a card for a white farmer passed through the machine, a counter for each of these categories would be increased by one. The card was robust enough to pass through the card reading machine several times, to count different categories or to verify the results.
The countdown went so quickly that the state-by-state numbers required for distribution by Congress were certified before the end of November 1890.
The rise of the punch card
After his success in the census, Hollerith went into business selling this technology. The company he founded, the Tabulating Machine Company, later became International Business Machines — IBM. IBM led the way in perfecting card technology for recording and tabulating large data sets for a variety of purposes.
In the 1930s, many businesses used cards for record keeping procedures, such as payroll and inventory. Some data-hungry scientists, especially astronomers, also found the maps handy. IBM then standardized an 80 column card and developed punching machines that would change little for decades.
Card processing became a branch of the powerful computer industry that flourished after World War II, and IBM would for a time be the third largest company in the world. Card processing served as the scaffolding for the much faster, space-saving purely electronic computers that now dominate, with little evidence from the old regime.
Those who have grown up knowing computers only as easily portable devices, with which one can communicate by the touch of a finger or even by voice, may not be familiar with computers the size of a play from the 1950s and 1960s, where the primary means of loading data and instructions was to create a deck of cards on a punch machine and then feed that deck into a card reader. This persisted as the default procedure for many computers until the 1980s.
As computer pioneer Grace Murray Hopper recalled of his early career, “Back then, everyone used punch cards, and they thought they would use punch cards forever.”
Hopper had been an important member of the team that created the first commercially viable general-purpose computer, the Universal Automatic Computer, or UNIVAC, one of the behemoths of card reading. Rightly, the first UNIVAC delivered, in 1951, was intended for the US Census Bureau, always eager to improve its data processing capabilities.
No, computer users wouldn’t use punch cards forever, but they did use them as part of the Apollo moon landing program and during the height of the Cold War. Hollerith would likely have recognized the direct descendants of his 1890s census machine almost 100 years later.
This is an updated version of an article originally published on October 15, 2019.