FAST AND HEAVY RAILWAY SERVICE. 265 
month in question was 294 tons, which shows the unfavor- 
able load conditions very forcibly. Increased service would 
improve this notably. The average amperes per train 
during the same period were 986, showing an aver- 
age input at the wusual voltage of 625 of about 600 
k. w. With a 500 ton train a speed of thirty-five to forty 
miles per hour could be reached, and on one occasion a 
1900 ton train was taken through the tunnel up grade. 
The drawbar pull in this case reached 63,000 Ibs. Fig. 138 
shows the current required for acceleration and running 
of a moderate train (875 tons) on the grade. The severe 
character of the work is sufficiently evident, and the effect 
on the economy of the power station of an intermittent load 
of this kind is obvious. The plant efficiency with the 
three locomotives is very materially increased. 
These General Electric Baltimore & Ohio locomotives 
were intended for very heavy service at moderate speeds 
about thirty miles per hour—but on a spurt of the 
engine alone up the grade more than double this has been 
  
reached. 
A radically different type of locomotive intended for a 
different class of service is the Westinghouse-Baldwin 
machine shown in Fig. 139. It is builtalong the lines of a 
motor car, and is in fact a combined baggage car and loco- 
motive. It ie thirty-eight feet long and eight feet wide 
and weighs complete eighty tons. The eight forty-two- 
inch driving wheels are mounted on two trucks with un- 
usually long wheel base. On each axle is a 250 h. D 
geared motor. By this means lighter and cheaper motors 
can be used than with the direct coupled construction. 
The gearing is arranged for a full speed of seventy-five 
miles per hour, as the locomotive is designed for fast 
passenger service. As in the Baltimore & Ohio locomotives 
the motors are arranged for series-parallel control. 
The problem of distributing power to units of so great 
capacity as these is serious. For tunnel work and perhaps 
for general work on special tracks, the center rail distribu- 
tion used on the Nantasket road is to be preferred toany-