Published in 1831, this work forms part of a collection of introductory volumes suggested by Henry, Lord Brougham and Vaux, the Lord Chancellor, for the Society of the Diffusion of Useful Knowledge. Due to the exceptional mathematical ability of its author, however, it outgrew its original plan and has since been seen as a rather more ambitious project. Praised by Somerville’s contemporary Sir John Herschel for its presentation of general astronomical theories and the mechanical principles employed in their derivation, the work was a tour de force of scientific and technical exposition. It is especially remarkable both for its author’s firm grasp of the subject, especially given her lack of formal mathematical training, and for its clear outline of Newtonian philosophy for a popular audience.