Page:Popular Science Monthly Volume 92.djvu/415

 Motor Trucks Pull Subway Cars

Construction work is facilitated by trusty gaso- line tractors that rush materials where needed

��MOTOR trucks are todaj' running in New York's subways. To be sure, they are not carrying passen- gers, because the portions of the tubes in which they are utilized are not yet com- pleted. Still, they are performing the very good service of rapidly transporting earth and rock, or bricks and steel, from one point in the system to another. The great amount of material which must be handled inside of the tubes may be realized when it is considered that the streets over the subway have to be kept open while the construction is going on. The torn-up portions of the roadway have to be put down just as soon as the con- crete roof is finished, leaving the placing of the rails, switches, and signal equip- ment for a later time. In order not to impede street traffic, the shafts down which the material is dropped are placed as far apart as possible. This makes long hauls necessary inside the tube itself.

As the current will not be turned on in the third rail until the regular passenger trains are put into operation, the problem of getting long, sixty-foot rails and heavy

��switches to the proper points on hand cars seemed too formidable for solution. Finally the superintendent decided to use a regular motor truck fitted with flanged wheels. There was none of the smoke and steam that accompany the use of locomotives. Moreover the regular flat car was rendered unnecessary, because the motor truck was converted into a tractor with a fifth-wheel at the rear instead of the usual body.

Ten to fifteen tons of sixty-foot rails are in this way pulled by a one-ton truck. The weight of the front ends of the rails rests on the truck fifth-wheel and the weight of the rear ends on an ordinary hand car, as shown in the illustration. The fifth-wheel support enables the truck to turn curves and run over cross-over tracks just like any locomotive. The truck is furnished with a searchlight mounted high on a rod extending up from the dash. This and a regular truck horn give men working along the. track a warn- ing of the approach of the unusual vehicle.

This adaptation of the familiar motor truck has much facilitated the work.

���A fifth-wheel is mounted on the rear of the motor truck. Rails and beams ride on it and on the small hand car in the background. There is no smoke, as with an ordinary locomotive

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