An account is given of the emergence of the concept of work as a basic component of mechanics. It was largely an achievement of engineer savants in France during the Bourbon Restoration , with Navier, Coriolis and Poncelet playing the major roles. Some aspects of the eighteenth-century prehistory are described, and also concurrent developments in French engineering. The principal problem areas were friction, hydraulics, machine performance and ergonomics, and especially in the last context the developments became involved with social and (...) even philosophical movements in the 1820s. Education played an important role throughout; several of the principal sources are textbooks. (shrink)