In 1834, Sir John Herschel, perhaps the most celebrated astronomer of his time, arrived at the Cape of Good Hope to spend four years observing the southern sky.

Among his many other talents he was an accomplished artist, skilled in the use of an optical device known as a camera lucida. During these four years Herschel produced more than a hundred exquisite landscape sketches, some depicting the Feldhausen estate in the suburb of Wynberg, where he and his family lived, others meticulously recording scenes that enlivened his trips to Cape Point, to Table Mountain, to Hout Bay and to places in the farther reaches. Among the latter were Caledon, Franschhoek, Stellenbosch and Paarl.

These Herschel landscape drawings are an almost unmatched contribution to the artistic and historical record of the Cape in the early nineteenth century. They are reproduced in this title, together with a narrative text and background material that firmly set the illustrations in their social and geographical context. The result is an evocative picture of the Cape Peninsula and its environs at a time when they were still largely wild.

This book, which has been in the making for some eighteen years, would never have begun were it not for Dr. David Dewhirst in 1976 kindly having shown the author a packet of papers in the archives of the Cambridge Obser vatories. These letters and miscellaneous papers of Fearon Fallows sparked an interest in the history of the Royal Observatory at the Cape of Good Hope which, after the diversion of producing several books on later phases of the Observatory, has finally resulted in a detailed study of the origin and first years of the Observatory's life. Publication of this book coincides with the 175th anniversary of the founding of the Royal Observatory, e.G.H. Observatories are built for the use of astronomers. They are built through astronomers, architects, engineers and contractors acting in concert (if not always in harmony). They are constructed, with whatever techniques and skills are available, from bricks, stones and mortar; but their construction may take a toll of personal relationships, patience, and flesh and blood.

This book, which has been in the making for some eighteen years, would never have begun were it not for Dr. David Dewhirst in 1976 kindly having shown the author a packet of papers in the archives of the Cambridge Obser vatories. These letters and miscellaneous papers of Fearon Fallows sparked an interest in the history of the Royal Observatory at the Cape of Good Hope which, after the diversion of producing several books on later phases of the Observatory, has finally resulted in a detailed study of the origin and first years of the Observatory's life. Publication of this book coincides with the 175th anniversary of the founding of the Royal Observatory, e.G.H. Observatories are built for the use of astronomers. They are built through astronomers, architects, engineers and contractors acting in concert (if not always in harmony). They are constructed, with whatever techniques and skills are available, from bricks, stones and mortar; but their construction may take a toll of personal relationships, patience, and flesh and blood."

Explore Twisted, the Python-based event-driven networking engine, and review several of its most popular application projects. It is written by community leaders who have contributed to many of the projects covered, and share their hard-won insights and experience. Expert Twisted starts with an introduction to event-driven programming, explaining it in the context of what makes Twisted unique. It shows how Twisted's design emphasizes testability as a solution to common challenges of reliability, debugging, and start-to-finish causality that are inherent in event-driven programming. It also explains asynchronous programming, and the importance of functions, deferreds, and coroutines. It then uses two popular applications, treq and klein, to demonstrate calling and writing Web APIs with Twisted. The second part of the book dives into Twisted projects, in each case explaining how the project fits into the Twisted ecosystem and what it does, and offers several examples to bring readers up to speed, with pointers to additional resources for more depth. Examples include using Twisted with Docker, as a WSGI container, for file sharing, and more. What You'll Learn Integrate Twisted and asyncio using adapters Automate software build, test, and release processes with Buildbot Create clients and servers with Autobahn Transfer files with Magic Wormhole Distribute cloud-based file storage with Tahoe LAFS Understand HTTP/2 with Python and Twisted Support for asynchronous tasks using Django Channels Who This Book Is For Readers should have some Python experience and understand the essentials of containers and protocols, but need not be familiar with Twisted or the associated projects covered in the book.

The study of cataclysmic variables - interacting binary stars containing a white dwarf accreting from an orbiting companion - is undergoing an exciting renaissance, as it embraces observations at all wavelengths. Cataclysmic variables allow, in particular, the direct and detailed study of equilibrium and non-equilibrium accretion discs; in turn these developments also help in our understanding of X-ray binaries, black holes and active galactic nuclei. This timely volume provides the first comprehensive survey of cataclysmic variable stars, integrating theory and observation into a single, synthesised text. An introductory chapter gives the historical background of studies of cataclysmic variables. The author then goes on to give an up-to-date review of both the observations (at all wavelengths, and over all time-scales), the theories, the models of the structures and accretion processes believed to be involved. A very detailed bibliography is also provided to guide the reader to pertinent primary literature.