Recent blue decorative boards. Octavo. Item #7085
This is one of the few papers which shows Babbage as a capable experimentalist and as a master of classification. During the period when Babbage was preoccupied with the construction of the calculating engine, he and John Herschel undertook to investigate the ten earthshaking discovery of Arago: a copper disc rotating next to a magnetic needle tends to "drag" the needle from its position of rest. In the course of this investigation Babbage and Herschel came very close to discovering electromagnetic induction, seven years before Faraday. They even went as far as concluding that time delay and magnetic change must be responsible for the rotation, but fell short of realizing that a totally new phenomenon need be postulated: the induction of eddy currents.