Engineering Wonders of the World
Volume I

^T^ANQEM8\T OF SUBJECTS. A word as to the arrangement of the articles. From the point of view of mere symmetry a grouping of subjects, each having its items set in chronological order, was advisable. On the other hand, the general reader would undoubtedly prefer a frequent change of topic ; so, out of consideration for him, grouping has been sacrificed in favour of a general distribution of subjects. This course made it necessary to supply an exhaustive index, in which the facts scattered over the work are brought together in due order. OUR ILLUSTRATION A large proportion—roughly two-fifths—of the total page space is devoted to illustrations. These fall under two main heads—the pictorial, to show the progress of work ; the diagrammatic, to demonstrate a principle, a function which diagrams perform more effectively than mere verbal explanation. We have added a number of sketches—such as those giving a bird’s-eye view of the Man- chester Ship and Panama Canals and the London Tube Railways— which present a subject in a manner not attainable by a photograph, a map, or a diagram. The photographic cuts are based upon originals selected carefully, and we trust that the reader will concur with our opinion that as a collection they are thoroughly representative.