Danilo Capecchi. The Problem of the Motion of Bodies: A Historical View of the Development of Classical Mechanics. (History of Mechanism and Machine Science, 25.) Dordrecht/New York: Springer, 2014. $169.99 (cloth).Agamemnon R. E. Oliveira. A History of the Concept of Work: From Physics to Economics. (History of Mechanism and Machine Science, 23.) Dordrecht/New York: Springer, 2014. $159.99 (cloth).