This case study is a historic analysis of the developments that resulted in the electric telegraph. It describes a fascinating development in the early nineteenth century. It is a story about communication. Long distance communication, that had already developed with the optical semaphore system created by Claude Chappe in revolutionary France. But now electricity became—next to its capability to transport power—also a carrier of information. On two different places in the same period of time, based on different concepts, two parallel developments took place that would change the world. It was the development of both the needle telegraph and of the electro-magnet telegraph. In Britain it were the cooperative efforts of William Fothergill Cooke and Charles Wheatstone that created the first telegraphic engines; the needle telegraph. After experiments with railway telegraphy proved its viability, it resulted in a telegraph fever when also the public and companies discovered this new means of communication. Combined with the continuous improvements in telegraph machines—such as the ABC telegraph—, it created an industrial bonanza of telegraph service providers and equipment manufacturers. However, soon the sprawl of non-standardized systems, combined with traffic congestions and numerous delays, created disgruntled users. Then, the ‘public interest’, a concern for British policy makers of that time, resulted in the nationalization of the telegraph industry in 1870. In the US is was Samuel Finley Breese Morse, an artist that turned into an inventor, who constructed—with the help of some friends like the “mecanicien” Alfred Vail—the Morse telegraph that would dominate electric telegraphy in the decades to come. From the first idea in 1832, to the awkward prototype of 1837, to the 1840-patented Morse system with his system of “dots and dashes”, took a while. Then, after the first telegraph line in 1843— publically funded by the US-Congress in 1843—would start a similar industrial bonanza when investors grasped their opportunities and created a multitude of telegraph lines in the Eastern US. This pioneering phase of telegraphy resulted in dozens of syndicates offering telegraph services. The following period of mergers and acquisitions would lead to the dominance of a private monopoly by the Western Union Telegraph Co. This is a story about totally different basic innovations that were both were part of clusters of innovations that in totality represents the invention of the electric telegraphy. The book describes the work of the many individual entrepreneurs, engineers and scientists. It places—analyzing the French Revolution and its aftermath in detail—the inventions in the context of Europe in the first half of the nineteenth century; the 'madness of times', its wars and revolutions. It tells about the contributions of 'the gentlemen of science' and the ‘engineers’, but also the ‘entrepreneur inventors’. Their contributions resulted in several 'clusters of innovations' and ‘clusters of businesses’, described in detail (including patent wars, mergers and acquisitions, and applications). Both from the micro-perspective of the individual entrepreneur, scientist and inventor, as well as the macro-perspective of their influence on society, the basic innovations are described. The book gives the reader a view on the effects of technical change caused by the application of ‘electricity’, how it influenced daily private and working life, and how it affected society. It shows an important aspect of the Second Industrial Revolution that created the foundations for our present society. This book is part of series of books (the Invention Series) that covers the inventions within the General Purpose Technologies that fueled breakthrough technological changes. Other titles include: 'The Invention of the Steam Engine', 'The invention of the electro-motive Engine', ‘The Invention of the Electric Light’, ‘The Invention of the Communication Engine ‘Telegraph’’, and ‘The Invention of the Communication Engine ‘Telephone’’. Commercial versions are available through Amazon.