Railroad Location. 97 



5th. —To keep the cost of the surveys as low as possible consistent 

 with obtaining the above results. 



It may be well at this point to explain briefly for the benefit of the 

 student, the terms used, with which he may not be familiar, and which 

 are in a measure peculiar to railroad work. 



In the preliminary selection of a route, the financial interests of a 

 proposed new road, or the directors, and traffic officials of an existing 

 road, to which an extension or branch is to be added, will have probably 

 as much to say as the engineer. It is at this stage of the proceedings 

 that what may be called the preliminary reconnaissance is made the 

 object of which is ordinarily very general, and the results of 

 which are generally made the basis of a report to the officials 

 of the company on the character of the country, probable 

 character of the road, i.e., alignment and grade, rough estimate of cost 

 per mile, and volume of traffic, immediate and future ; and on this report 

 a determination is generally reached as to whether further surveys should 

 be made. This phase of reconnaissance, though of the utmost import- 

 ance to the future of the road, will not be further touched on here, as 

 ability to conduct such reconnaissance and make a proper report, is an 

 art, proficiency in which can be only the result of extensive experience, 

 not only on location surveys, but also of the operation and maintenance 

 of railroads and involves a discussion of the theory of railroad location 

 beyond the purpose of the present work. 



The second phase of reconnaissance may be called reconnaissance 

 for detail, and this is what will be generally understood by the term 

 reconnaissance when referred to hereafter. It is the reconnaissance 

 made by the locating engineer to familiarize himself with the details of 

 the country and determine what portions shall be covered by the pre- 

 liminary surveys. 



Ifc must be thoroughly understood by the student that the problem 

 confronting the locating engineer is not the location of any line through 

 a given country, but the location of the best line ; such a line that no 

 other line can be built, through the same country with the same, or 

 better ruling grades, with less expenditure at the same unit prices. 



The location of a line involving the smallest cost of construction is 

 by no means the only desirable result to be obtained ; economy of 

 operation plays an important part, and hence Mr. McHenry's definition 

 of engineering, which applies especially to railroad location, that 

 " Engineering is the art of making a dollar earn the most interest." 

 Therefore, of two lines even with the same ruling grades and maximum 

 degree of curve, the one which costs the least to build may not be the 

 most economical, because on account of a larger total number of degrees 

 of curvature, or larger total rise and fall, or both, or a greater length of 

 line, it may cost so much more to operate, that it will not earn as large a 

 rate of interest on the money invested as the other. 



