Sir John Frederick William Herschel (1792-1871) - astromer, mathematician, chemist - was one of the most important English scientists of the nineteenth century. Son of the famous astromer William Herschel and nephew of Caroline, he was persuaded by his father to pursue the astromical investigations William could longer undertake; John's subsequent career resulted in a knighthood and a lifetime of accolades. Outlines of Astromy (1849), an updated and expanded version of his 1833 Treatise on Astromy, went through eleven editions in two decades and was translated into several languages. Outlines examines terrestrial and celestial phemena, providing the reader with a wide range of kwledge about the physical world as a whole. The work is an important textbook, the object of which 'is t to convince or refute opponents, r to inquire ...for principles of which we are all the time in full possession - but simply to teach what is kwn'.