somerville was requested by lord brougham to translate for the society for the diffusion of useful knowledge the "mécanique céleste" of pierre-simon laplace. laplace had, in five exhaustive volumes, summed up the current state of gravitational mathematics and "mécanique céleste" was acclaimed as the greatest intellectual achievement since the "principia". somerville produced not a translation, but an expanded version of the first two volumes. she wrote a standalone exposition of the mathematics behind the workings of the solar system, of which she said "i translated laplace's work from algebra into common language". it was published in 1831, under the title of "the mechanism of the heavens". it made her at once famous. "mechanism" was set as a textbook for undergraduates at university of cambridge until the 1880s.