When Computers Were Human

  • David Alan Grier
Princeton University Press: 2005. 412 pp. $35, £22.95 0691091579 | ISBN: 0-691-09157-9

We work from morn till night,  For computing is our duty; We're faithful and polite,  And our record book's a beauty; With Crelle and Gauss, Chauvenet and Peirce,  We labor hard all day; We add, subtract, multiply and divide,  And we never have time to play. (from The Observatory Pinafore by Winslow Upton, 1879)

Crunch time: large numbers of people used to do the calculations now done by electronic computers. Credit: LIBRARY OF CONGRESS

Human computers certainly did work hard all day, and had the aches and pains to show for it: elbow joints inflamed from cranking calculator handles, or fingers and thumbs cramped from pencilling figure after figure on to graph paper. For two centuries the modern scientific enterprise was built on their efforts. Yet every time a logarithm was looked up, or the value of a Bessel function checked, a debt was incurred that was rarely acknowledged. And now the human computer has vanished from history.

People do not disappear from our collective memory by accident. Forgetting is not a passive process: people are forgotten for a reason. Two decades ago, the sociologist Steven Shapin noted pointedly that the lab technician, although essential to making an experiment work, rarely appeared in accounts of successful scientific work. But if something went wrong, the finger was pointed at human interference. Erasing the human hand was part of the means by which an experiment was seen to reveal aspects of nature, rather than aspects of society.

David Alan Grier's recovery of the wonderfully rich story of human computers not only allows us to repay a debt, but also to ask why human computers were made to disappear in the first place. They were drawn from the margins of the scientific establishment. Many were women. Nicole-Reine Lepaute, for example, the well-to-do wife of a royal clockmaker, was one of a trio — said to be the first astronomers to divide the labour of scientific calculation — who calculated the orbit of Halley's comet in time for its perihelion of 1758. Many later female computers came from much poorer backgrounds.

Male computers, too, were relatively disadvantaged. Many of the computers employed in Gaspard de Prony's Bureau du Cadastre, a factory of calculation, were hairdressers and wigmakers who had fallen on hard times following the French Revolution. Often the reason was financial: women, boys and immigrants made for cheap and willing labour. It was even said of Harvard Observatory, run by the relatively progressive Edward C. Pickering and staffed by college graduates, that the “computers are largely women who can be got to work for next to nothing”.

By the Second World War, the heyday of human computers, they were routinely referred to as ‘girls’. Indeed, managers calculated ‘girl-years’ of effort, and even defined the ‘kilogirl’, a unit for measuring work. But, as Grier emphasizes, “even at this date, computing was not the sole domain of women. It was really the job of the dispossessed, the opportunity granted to those who lacked the financial or societal standing to pursue a scientific career.” For computing offered people from the margins an entry into the scientific world — an opportunity that they often grasped with both hands.

It is notoriously difficult to recover details of the lives of ordinary people: they rarely leave their words for posterity, and can be glimpsed only through the writings of their social superiors. Many more words have been written about Napoleon than about his foot soldiers. Indeed, it would take the imaginative power of a Tolstoy to reach back and reanimate the human computers labouring in the calculating offices of the eighteenth and nineteenth centuries. Despite Grier's industry, many still remain anonymous.

But Grier triumphantly achieves his aim when discussing the twentieth-century human computer, as many are alive to tell their tales. Take, for example, the life of Gertrude Blanch. Born Gittel Kaimowitz in Poland, and educated well, she fled the pogroms with her family. In the United States, Gertrude struggled for years to find employment that matched her mathematical ability. But a chance meeting in 1937 with the director of the Mathematical Tables Project, Arnold Lowan, who shared her background, presented her with an opportunity that she gladly grasped. By 1940, the project was the project was the largest scientific computing organization in the United States, and Blanch was one of its organizers. Grier traces in detail how Blanch's later career was blighted by the FBI's suspicions that she was a communist sympathizer.

Blanch's story is told with Grier's characteristic verve. But why did she, and her fellow human computers, disappear from history? Partly it was a familiar case of science erasing the traces of its human creation. But also the human computers suffered from the need to provide their successor with a suitable genealogy. At the seminal Moore School summer classes, where the team that built the ENIAC (the Electronic Numerical Integrator and Computer) spoke of new stored-program computers, listeners “heard a somewhat fanciful history of calculating devices that ignored the contributions of [human] computers”. This “was an attempt to build a distinguished lineage for the electronic computing machine, a pedigree that ignored the influence of commerce and the hard labour of human computers.”

Left undisturbed, victors write history.