“A tour-de-force. . . . Eminently well written, the story lines immerse the reader in situations and events that provide real insight into the roles of numerous amateur (here meaning not formally trained) astronomers in moving the field forward, as well as how professional astronomers have worked with amateurs to the advantage of both. Hirshfeld’s writing style brings the 19th century back to life and provides a rich tapestry of astronomical history.”