12 LOCATION. 



ported upon into natural divisions of similar characteristics, 

 giving distances, grades and controlling points of each. He 

 should describe, classify and approximately estimate the ma- 

 terial to be moved and other work to be performed, giving 

 averages per mile and totals for each section, and furnish an 

 approximate estimate of the cost per mile and total cost of 

 the completed railway. Small scale maps and profiles show- 

 ing general features, elevations and distribution of ruling 

 grades should accompany such reports, whenever necessary. 



The fundamental principle of good location is common 

 sense. 



VOLUME OF TRAFFIC. 



Fixed charges are but slightly, or not at all, affected by 

 variations in volume of traffic. "General" operating ex- 

 penses are affected only by considerable changes of volume, 

 while the more direct expenses of operation vary more or 

 less closely with the tonnage or passengers transported. 



The effect on cost of operation of the number of trains oper- 

 ated is much more direct, than of the actual number of passen- 

 gers or tons transported, hence the effect on the cost per train- 

 mile is used as the basis for all economic comparisons, and 

 the actual cost per train-mile should be ascertained in all 

 cases, when possible. 



Under practical conditions, the first trains operated cost 

 more, and additional trains cost less than the average cost 

 of all. 



The average cost per train-mile for the United States is 

 probably not far from $1, and this amount may be used for 

 convenience, when more exact data are lacking. 



When the number of trains is affected without affecting the 

 total cars or tonnage, the cost per train-mile added or saved, 

 may be assumed at 60 cts. in default of more exact data. 



The cost of assistant engine service, extra cost of heavier 

 engines and of all other items affecting the cost per train-mile, 

 under special conditions, must be added or subtracted from 

 the train-mile cost first assumed (see Ruling Grades). 



If better estimates of cost are not available, estimate 

 assistant engines at $7,500 per annum (per day of 12 hours) 



