Engineering Wonders of the World
Volume I

contributions. The balance is based upon first-rate information, much of it supplied by experts whom pressure of business prevented from contributing at first-hand. Our debt to these gentlemen we here acknowledge gratefully. In length, the articles vary considerably, according to the nature of the subject. They are short where brevity suffices ; long where the subject demands a more or less detailed explanation. TH 8 SC0T8 OF TH8S8 V0LUM8S. As the title implies, the whole world is laid under contribution for our material, selected on its own merits. English and Continental railways, for instance, receive little notice, being overshadowed by the more imposing, romantic, and extensive systems of America, Asia, and Africa. For mountain tunnels we go to the Alps ; for canals to Panama, Suez, and the United States ; a notable cableway is found in the Andes ; the chief aqueducts noticed are in Australia, the United States, and England. And so on. Some articles, such as those on shipbuilding and power signalling, are quite general in their application. Room has been made for descriptions of unique feats like the transportation of the parts of the train-ferry Baikal to Central Asia. Here and there we bring to notice subjects about which little is generally known—for example, the underpinning of large buildings. Nor has the mechanical side of engineering been neglected : our list of contents includes, among other mechanical items, the steam and electric locomotive and their new rival, the aeroplane. We have seen to it that the reader should have no reason to complain about lack of variety and comprehensiveness. Except in the first chapter, attention is confined almost entirely to engineering practice after the year 1800. A back limit had to be set somewhere, and this date is convenient, as the development of the steam engine and the many forms of engineering stimulated thereby belong to the nineteenth century. We may add that but few articles deal with work done prior to 1850, and these exceptions are justified by the character of the enterprises described. The Menai Straits and Saltash Bridges and the Thames Tunnel—to mention three —are worthy to rank with the greatest engineering feats of the present day, as any subsequent eclipse in point of size is compensated by the exceptional difficulties attending their construction.