A key challenge of studying the historical phonology of any language is how to reconstruct the pronunciation of periods before the availability of sound recording. Many studies of pre-twentieth-century pronunciation rely on sources that comment on how people spoke, or infer pronunciation from spelling variation or rhymes. This book is the ¿rst to investigate the phonology of nineteenth-century English based on a new kind of written source material: it examines pronunciation evidence provided by contemporary grammar books, and offers quantitative and qualitative analyses of the phonological commentary found in a collection of 258 English grammars published in Britain, Ireland, and North America during the nineteenth century. The nineteenth century has been described as the century of prescriptivism, and this book examines the tensions between prescriptive and descriptive approaches in the grammars. Individual case studies detail several linguistic features which were undergoing change and which were reportedly stigmatised at the time. Consonantal features include non-rhoticity, /h/-dropping and /h/-insertion, the WHICH-WITCH merger, /v/-/w/ interchange, and the pronunciation of -ing. Further studies chart variation in the vowel of BATH words, and in the diphthongs of words such as FACE and GOAT, which are characteristic of both RP and American English pronunciation. In exploring the potential of this understudied source material as evidence of historical pronunciation, this book contributes to the ¿elds of historical phonology, grammaticography, the study of prescriptivism, and historical sociolinguistics.