Once upon a time, equations that could not be solved analytically were solved numerically by teams of people who were, in many cases, capable of only rudimentary mathematics. More gifted mathematicians broke complex problems into algorithmic steps small enough to be worked by hand, and they would then be tackled by teams of "computers". This was normal for over 250 years, until they were replaced by digital computers in the mid-20th century.
Grier does excellent research, meeting with surviving computers and finding letters and other material. In one amusing source, he extracts details of the lives of the women who computed for Harvard Observatory in the late 19th century from a satire of a Gilbert & Sullivan opera written by a junior astronomer there.
As many of these computers through the history of the industry were women, this book may be of particular interest to those who follow the history of women in science. Grier is particularly taken by the story of Gertrude Blanch at the Mathematical Tables Project run by the National Bureau of Standards in the U.S., and devoted many pages to her life and work.
If the book has any weakness, it is only that these teams of computers were typically employed by governments, and descriptions of their work sometimes amounts to descriptions of bureaucratic politics, not a very interesting topic. This is offset, however, by amusing observations and excellent photographs illuminating the lives of these mostly forgotten precursors to modern computers.
