PRACTICAL TREATISE ON RAILWAY CURVES AND LOCATION, FOR YOUNG ENGINEERS. CONTAINING A FULL DESCRIPTION OF THE INSTRUMENTS, THE MANNER OF ADJUSTING THEM, AND AND OTHERS OF GENERAL USE IN THE PROFESSION. BY WILLIAM F. SHUNK, CIVIL ENGINEER. PHILADELPHIA: PUBLISHED BY E. H. BUTLER & CO. Pizz MAY 4 1881 Gift of P.C. zabody, 2. D. Entered, according to the Act of Congress, in the year 1854, by E. II. BUTLER & CO., In the Clerk's Office of the District Court of the United States, in and for the Eastern District of Pennsylvania. PREFACE. THE located line for railway is a series of curves and straight lines, or tangents. These are first plotted to a large scale from data gathered on preliminary survey. It is therefore desirable that all explorations should be made with extreme care, as upon their correctness depend, in no small degree, the labour and time required in location. It were better for accuracy that all angles should be made and recorded from the plates, and the needle used only as a test, or check. Good chaining is indispensable. Great attention, too, should be given to the proper use of the slope instrument. By these means a working map can be constructed in the office upon which the proposed location, grade lines, &c., may be traced with tolerable resemblance to fact. Still many errors attach to both data and map, and these, together with the unexpected obstacles encountered in the field, require ready knowledge of the means for overcoming them. It has been my design to present this knowledge to my younger fellows in the profession. I have endeavoured to |