A TREATISE ON THE METHODS EMPLOYED FOR BY MEANS OF LOCKS AND DAMS. BY B. F. THOMAS, United States Assistant Engineer, Member of the American Society of Civil Engineers, AND D. A. WATT, United States Assistant Engineer, Member of the American Society of Civil Engineers. FIRST EDITION. FIRST THOUSAND. NEW YORK: JOHN WILEY & SONS. LONDON: CHAPMAN & HALL, Limited. 1903. PREFACE. THE following treatise has been prepared in the hope that it may assist in meeting a want which has probably been felt by many engineers and others engaged on the improvement of rivers. With the exception of De Lagréné's "Cours de Navigation Intérieure," published in 1873, and which is now out of print, there is no work known to the authors which treats of this important subject except in a general way, or with sufficient detail for those engaged on actual construction or design. Much valuable information is to be found scattered through the various Government Reports relating to inland navigation, and matter of great interest has also appeared from time to time in various domestic and foreign publications. A search through these for information on any special point would, however, involve an expenditure of time and labor which few of those engaged in active work could give, even if the documents were accessible, to them. Moreover, since the appearance of De Lagréné's work many new methods have come into use, especially in America, and wider experience has been gained, and as experience is probably more necessary for successful work in this branch of engineering than in any other, owing to the imperfect understanding of the laws governing the flow of rivers, the authors believe that a treatise combining the results of theory and recent modern practice may prove of some utility in this field. They have accordingly endeavored to include all the important points of design and construction which are likely to be met with in ordinary practice, and the calculations have been simplified as far as possible so as to bring them within the range of those who do not possess a thorough technical education. It is hoped, therefore, that the book may prove of use not only to engineers, but also to inspectors, surveyors, and others who are engaged on the more practical side of work. The authors desire to acknowledge their indebtedness to Brigadier-General G. L. Gillespie, Chief of Engineers, U. S. Army, and to the Officers of the Corps of Engineers, for their courtesy in granting access to drawings and data connected with the works under their charge and permitting the publication of certain of them, and also to return thanks to certain civilian engineers for information on similar matters. Their thanks are also due to Major W. M. Black, Corps of Engineers, author of "The United States' Public Works," and to Mr. Edward Wegmann, author of "The Design and Construction of Dams," for permission to reproduce illustrations from |