“The wide range of the profession of an Engineer requires the assistance of many departments of science and art, and must call into employment important branches of manufacture. He can perform no great work without the aid of a great variety of workmen; and it is on their strength and skill, as well as on their scientific direction, that the perfection of his work will depend. The personal experience of one individual cannot fit him for the exigencies of a profession which is ever extending its range of subjects, and is constantly dealing with new and complex phenomena,—phenomena which are all the more difficult to deal with from the fact, that they are generally surrounded by such variable circumstances as render them incapable of being submitted to precise measurement and calculation, or of being made amenable to the deductions of exact science. Consequently, nothing is more certain than that he who wishes to reach the perfection of his art must avail himself of the experience of others as well as his own, and that he will not unfrequently find the sum of the whole little enough to guide him. And let no inventive genius suppose that his own tendencies or capabilities relieve him from this necessity. “There is no such thing as discovery and invention, in the sense which is sometimes attached to the words. Men do not suddenly discover new worlds, or invent new machines, or find new metals. Some indeed may be, and are, better fitted than others for such purposes; but the progress of discovery is, and always has been, much the same. _There is nothing really worth having that man has obtained that has not been the result of a combined and gradual progress of investigation._ A gifted individual comes across some old footmark, and stumbles on a chain of previous research and inquiry. He meets, for instance, with a machine, the result of much previous labour; he modifies it, pulls it to pieces, constructs and reconstructs it, and, by further trial and experiment, he arrives at the long-sought-for result.”