Those of us who had World War Two air force service will find this survey of the types of airborne computer in use then and later both nostalgic and interesting. Starting with the elementary slide-rule types of device that originated in World War One, McConnell explains how the increasing sophistication of aircraft necessitated the improvement of navigational aids. The same was true of bombing: early aviators merely threw the bomb overboard. With fast, high-altitude planes this method was impossible, and a range of sophisticated optical-mechanical devices was produced. All of the most important bombsight computers are mentioned, and excellent overviews of their methods of functioning are provided.

Some of this military technology found its way onto the war surplus markets, and the remarkably accurate and robust integrating devices found a place in many analog computers of the 1950s. Although they did not replace the Bush Torque Amplifier, the power output was often adequate to enable complex devices to be made.

This paper is interesting and well illustrated, and the bibliography is extensive and accurate.