William Huggins (1824-1910) was celebrated in his lifetime as the father of astrophysics. Huggins was also the author of numerous groundbreaking articles documenting his use of the spectroscope to analyze the light from celestial bodies. From the earliest days of his career Huggins was regularly in contact with other scientists, including astronomers, chemists, physicists, mathematicians and the makers of scientific instruments. Correspondents include Ernest Rutherford (pioneer of atomic physics), Thomas Romney Robinson (director of the Armagh Observatory), George Gabriel Stokes and Joseph...