176 POWER DISTRIBUTION FOR ELECTRIC RAILROADS. 
for all work requiring considerable and variable resistance 
in the armature circuit. It is therefore, particularly well 
adapted for railway work at varying speed, hoisting and 
similar severe service. In general properties, efficiency, 
power factor, regulation and so forth the two construc- 
tions are indistinguishable. 
  
FIG. 96. 
For effectively meeting the demands of railway service 
a motor must be simple, durable and easy to inspect and 
repair; it must also be capable of regulation in speed with- 
in rather wide limits, must have great initial torque, and 
must have a good efficiency. The first three mechanical 
qualifications the induction motor is amply able to meet.