*Though many human computers toiled alone, the most influential worked in organized groups, which were sometimes called computing offices or computing laboratories. These groups form some of the earliest examples of a phenomenon known informally as “big science,” the combination of labor, capital, and machinery that undertakes the large problems of scientific research.*

**When Computers Were Human**, p. 5.

David Alan Grier started his study of human computers as a labor of love. A simple comment by his grandmother, that she had taken calculus in college, made him curious. Out of that curiosity has come a history of computing before computers that is a must read for anyone interested in early computing or the history of mathematics. Starting with the appearance of Halley’s Comet in 1758, Grier traces the maturation of hand computing and its ultimate displacement by electronic computers.

Even though long calculations had been done by mathematicians in the course of their work for centuries, the laborious calculations required in the determination of celestial orbits and the preparation of tables of ephemerides for use in navigation were the first calculations taken on by groups of computers in a formal way. The first calculations described by Grier are those of the small “computing group” of Clairaut, Lalande and Lepaute on Halley’s Comet in the 1750s. By the 1800s, groups employing tens of computers were working for national observatories and almanac offices in Britain and by the end of the century, in the United States. In the 1900s, the largest computing groups added the compilation of tables to their burgeoning workloads. In the first half of the 20^{th} century, larger computing groups of more than one or two hundred computers started working on matters of defense, such as ballistics. These groups were more and more aided in their endeavors by the simple mechanical calculating devises constructed starting in the late 1800s. By the close of the Second World War, electronic computers were being constructed, and within two decades of the war, the large computing offices that had been a fixture of scientific research for over a century had been replaced by electronic computers. And with the closing of these computing offices, a whole segment of the scientific community went out of existence

Grier brings to life these men and women who, for the most part, have been forgotten by history. They worked long hours doing repetitive calculations for some larger project they knew little or nothing about. In the large computing offices, calculations were broken down into individual steps by planning teams made up of people with some background in mathematics. The workers were for the most part not mathematicians. Most were high school graduates in need of work.

The strength of this book is its breadth of research and its human touch. However, this is also its greatest weakness. In making this book accessible to the general public, which it very much is, the author has included no mathematics. The names of mathematical functions and the like are mentioned, but no description at any level is made of the actual calculations performed by the computing groups. No example of a computing sheet is given so the reader can get a feel for the work done. I believe that anyone interested in this topic would be able to handle a brief description of the work done. So even though I feel that I learned a lot about the lives of these men and women, and the politics that shaped the computing community, I have gained no knowledge of the actual work done. That said, this is still a well written, informative and enjoyable work. One that should take its rightful, and long empty, place on the shelf next to the myriad volumes on the history of the computer.

Amy Shell-Gellasch is currently a freelance math historian living in Grafenwoehr Germany while her husband is on a three year tour of duty in Germany. She received her bachelor's degree from the University of Michigan in 1989, her master's degree from Oakland University in Rochester, Michigan in 1995, and her doctor of arts degree from the University of Illinois at Chicago in 2000. Her dissertation was a biographical piece on mathematician Mina Rees. Most recently, she conducted research with V. Fredrick Rickey on the history of the Department of Mathematical Sciences at the United States Military Academy, where she was an Assistant Professor.