10 LOCATION. 



Rapid exploration lines, especially when in timber, should 

 "be run with compass bearings; in many cases the method of 

 stadia readings will also expedite progress. The time-hon- 

 ored custom of conducting explorations from behind the tran- 

 sit should be changed for a more intelligent method. 



The reconnoissance should be of an area rather than of a 

 consecutive line, all lines or combinations of lines connect- 

 ing controlling points being studied as a whole. It should 

 be the effort of the engineer to first ascertain the position, 

 character and limiting effect of controlling points, natural or 

 otherwise; afterwards connecting such points most advan- 

 tageously, and finally filling in intermediate details to the 

 best advantages. 



No local conditions of rocky slopes, swamps, brush, timber, 

 etc., should be allowed to unduly influence the Engineer as to 

 their real effect upon the total estimate. He should also 

 remember that alternate lines will be compared upon the basis 

 of completed cost, and not on the cost to subgrade only, and 

 finally that it is not the object of location to secure a line of 

 uniform low cost, but of least total cost. It is a common 

 error to reject routes with short sections of heavy construc- 

 tion cost in favor of more uniform although inferior routes of 

 greater total cost. 



The route of best grades and alinement should always be 

 first projected, working back to the final and most economical 

 route. Working in the reverse order usually results in inferior 

 location. 



The possibility of obtaining a very good line should not 

 preclude the search for a better one; the greatest and most 

 costly location errors occur most frequently in prairie 

 regions. 



Valley locations are usually projected from "point to point" 

 on the line of shortest distance, when the stream is unimport- 

 ant, otherwise the convex angles of stream on one side and 

 the slopes on the other form controlling points if not modified 

 by the additional latitude of choice afforded by the two sides 

 of the stream, or any combination of same. 



Bench, plateau or prairie locations are usually projected on 

 routes of most uniform grade and direction between controll- 



