202 POWER DISTRIBUTION FOR ELECTRIC RAILROADS. 
street railway in several very important particulars. First, 
the speed is on the average very much higher; second, the 
stops are relatively much less frequent; third, the average 
distance between generator and motors is far greater; and 
fourth, the average power per car is considerably more in 
amount. 
As regards the first count, the actual speed on all elec- 
tric roads is apt to be overestimated. Most cars on street 
railways have an average speed, including stops, nearer five 
miles an hour than ten, as can readily be figured from the 
hours of running and the average daily mileage. Now 
  
YIC. 107 
for runs between town and town much greater speed than 
this is desirable and can be readily reached in the absence 
of traffic obstructions. 
The interurban line should be able to make at least 
double the average speed of the street railway proper, and 
this means from twelve to eighteen miles per hour includ- 
ing ordinary stops. The maximum speed corresponding 
to this is likely to be from twenty to thirty miles per hour, 
seldom, however, the latter figure. The general running 
speed is likely to be between fifteen and twenty miles per 
hour. 
These speeds call at once for modifications of standard 
cars and trucks. Under such conditions the common single 
truck is positively unsafe on ordinary track, and recourse