Astronomical photometry is the science of measuring the brightness and colours of stars and other celestial objects. It is a technique at the very heart of modern astrophysics. This authoritative volume traces the fascinating historical development of astronomical photometry – from visual techniques at the time of William Herschel in the 1780s, through to the birth of photometry with charge-coupled devices in the 1970s. In this intriguing survey, we see how the advent of new technology has revolutionized the science of photometry at each stage of its development, and what dramatic advances have been achieved, despite several major disasters – especially in the practice of photographic photometry. This book also clearly illustrates the critical relationship between the development of a science and the technology it uses. This volume provides professional astronomers with a valuable guide to the background and development of this fundamental technique. It will also be of great interest to amateur astronomers and historians of the physical sciences.