Originally published in French in 1951, translated and published in English in 1957, it was re-published by Willmann-Bell in 1984, with extensive appendices giving sources of even more information. This book certainly shows its age in its inclusion of topics such as silvering a mirror at home (don't do it - lots of nasty chemicals), and its omission of Dobsonian ideas in its section on alt-az mounts - it pre-dates that innovation. However, for a discussion of designing an optical system, to grinding and polishing a mirror, and especially for details of how to rigorously test its figure, Texereau is unparalleled.
Several other books include six or a dozen telescopes you can build, with some pictures of the final product, and the builder's musings on what problems he faced in building it; Texereau takes you through all the messy details you need to know before making a lot of time-consuming mistakes. Again, much of it can be skipped; he spends four chapters on classical Cassegrains, which I gather is his favorite telescope design. But this book is highly recommended for anyone considering pushing glass.