Friday, September 15, 2023

Punched cards transformed data processing

© Mark Ollig

Herman Hollerith graduated from Columbia College in New York with an engineering degree in 1879.

After graduating, he researched data collection and organization as a statistician during the 1880 US Census.

He observed the time-consuming and labor-intensive hand-counting tabulation of data points, including name, age, gender, profession, marital status, birthplace, and more.

Hollerith began developing a punched card tabulating machine system in 1881 while working for the head of the US Census Bureau’s Division of Vital Statistics, where he got the idea to mechanize the repetitive tabulations involved in census work.

Some folks call them punch cards; others say punched cards. For today’s column, I refer to them as punched cards, whether punched with a hole or not.

Hollerith wanted to automate the process for the US Census and decided to integrate punched cards with his new system.

He was inspired by Joseph-Marie Jacquard’s invention of the Jacquard loom in 1801, which used punched cards made of heavy pasteboard to control the fabric weaving process.

Each card had a grid of holes corresponding to the loom threads. When a card was inserted into the loom, the holes allowed certain threads to pass while others were blocked, enabling the loom to weave the desired pattern.

Different patterns could be created by changing the punched cards, making it possible to produce a variety of woven cotton fabrics.

Hollerith’s tabulating machine used heavy stock paper-punched cards to read, store, and process data.

His first punched cards used 12 rows and 24 columns, with holes representing specific data and/or characters.

In the strictest sense, his punched cards did not use the binary system but appeared to represent binary numbers. With the binary system, a hole in a specific card location represents a one, and the absence of a hole represents a zero.

With Hollerith’s punched card, each column could represent a different value, such as a letter, a number, or a special character. A punched hole in a specific location on a punched card might indicate marital status. A hole represents marriage, and no hole represents single.

When using Hollerith’s tabulating system, a human operator opens the punch card reader and positions a card between two metal plates resembling a waffle iron. The tabulating machine electrically reads the data from the punched card when the plates are closed.

The machine accomplished this by passing spring-loaded metal pins through the card holes and into small cups filled with mercury, completing an electrical circuit that activated a peg counter to compute the number of pins making electrical contact and using this information to sort the individual data set points from the card.

The tabulating machine totals were displayed on electromechanical solenoid counters/accumulators and rang a bell informing the human operator that the data from a punched card had been read.

On Jan. 8, 1889, US Patent 395782 A, “Art of Compiling Statistics,” was granted to Herman Hollerith for a tabulating machine he described as an “electromechanical counter used in connection with the counting apparatus.”

The US Census Bureau was worried about completing the 1890 census before the 1900 census due to population growth and the already lengthy seven-year process of hand-counting the 1880 census.

In 1888, the US Census Bureau hosted a competition in which the winner would be awarded a contract for the 1890 US Census, which Herman Hollerith’s tabulating machine easily won.

For the 1890 census, the US Census Bureau leased over 100 Hollerith tabulating machines to process data using punched cards that were 3.25 by 7.38 inches with 12 rows and 24 columns.

The Minneapolis Times newspaper of June 30, 1890, mentioned the “counting machines” used in the 1890 census, adding, “It is expected that by the use of these machines, the results of the census will be known much sooner than they could be by any other known method.”

The 1890 US Census took under two years to complete, a substantial improvement over the 1880 census.

His tabulating machines processed the census data quickly and accurately, saving the US Census Bureau an estimated $5 million.

The population of Minnesota in 1890 was 1,301,826, while the entire US population was 62,979,766.

In 1896, Herman Hollerith founded the Tabulating Machine Company.

The same year, the New York Central and Hudson River Railroad began using his tabulating machines to audit their freight accounts and gather traffic statistics.

Tabulating Machine Company became Computing-Tabulating-Recording Company in 1911, which, in 1924, was renamed International Business Machines (IBM).

By 1928, most railroads in the United States used Hollerith tabulating machines to manage schedules, inventory, and freight.

IBM became the leading manufacturer of tabulating systems using Hollerith/IBM AA1-5081 square corner punched cards that measured 7.38 by 3.25 inches and were 0.007 inches thick.

The AA1-5081 punched cards had 80 columns, each with 12 rows with numbers zero through nine and two zones.

Developed in the late 1950s, FORTRAN (FORmula TRANslation), a high-level computer programming language, used Hollerith/IBM punched cards for its program code storage.

Hollerith’s use of punched cards laid the foundation for 20th-century computer data input, output, and storage using magnetic tapes, hard drives, and solid-state drives.

Born Feb. 29, 1860, in Buffalo, NY, Herman Hollerith died Nov. 17, 1929, in Washington, DC, at age 69.