300 



TRANSPORTATION 



by rail began to use the buses with the result that 

 passengers decreased in numbers on the trains. 



Along with the buses airlines have also developed, 

 and our modern airliners are carrying thousands of 



Courtesy Burlington Route 



FIG. 500. A STREAMLINED TRAIN 



passengers each year. This again has taken consider- 

 able traffic from the railroads. 



As a result of these developments in new modes 

 of land travel, the past few years have seen some most 

 interesting developments in rail transportation. The 

 railroads are investing millions of dollars in new 

 equipment in an attempt to regain their former posi- 

 tion of supremacy in land transportation. Some of our 

 most modern trains seem to belong to another age, 

 they are so different from the ones that we are so 

 accustomed to using. 



One of the principal points of competition which 

 the railroad faces in the airplane and bus is that of 



speed. Modern trains are being built to attain much 

 higher speed than was possible before. Speed has 

 been increased in several ways. First the use of alumi- 

 num and aluminum alloys has made it possible to de- 

 crease the weight of the train. Modern trains have 

 followed the example set by the automobile and bus 

 manufacturers with streamlined designs. The whistle 

 and bell, commonly seen on the top of the older style 

 locomotives, have been set back in the body of the 

 car. Vestibules are closed and the steps pull up when 

 not in use. 



One of the most radical departures in the new-type 

 train is the power plant. Instead of coal as a fuel, 

 many of them are using oil. The oil is used to drive 

 Diesel engines which in turn are used to turn electric 

 generators. The electricity resulting is then used to 

 drive electric motors that propel the train. This not 

 only enables more efficient use of the energy in the 

 fuel, but enables higher speeds and furnishes a supply 

 of power which is free of dirt and which is easily 

 controlled. 



The fact that these trains are able to reach much 

 higher speeds and maintain them over long distances 

 is evidence of their superiority over the older trains. 



Another significant advance in rail transportation 

 in recent years has been the air conditioning of trains. 

 On many lines today the air supplied to the cars is 

 cleaned and either heated or cooled, depending upon 



Courtesy Baldwin Locomotive Works 



FIG. 501. MODERN FREIGHT LOCOMOTIVE 



the outside temperature. Figure 500 shows a modern 

 streamlined train and Figure 502 shows how railroad 

 cars are air-conditioned. 



Exercise. Trace the mechanical energy of a Diesel 

 electric train to its remotest source through all of its 

 transformations. 



Of what importance is electricity in modern trans- 

 portation. Experiments in electrical transportation 

 were carried on in this countrv as early as 1835, but 



FILTER FORCED INTAKE \ '. , , H I n ,1 1 ; i I i / .- HUMIDITY CONTROt 



Courtesy The Pullman Company 



FlG. 502. HOW A RAILWAY COACH IS AIR-CONDITIONED 



