Roadbeds and Structures

Trackwork.

An outstanding development has been the con sideration given to the distribution of metal in switches, frogs and crossings to provide uniform strength throughout. Heat treated and high-tensile bolts are frequently specified for the as sembly of frogs and crossings. Heavier track structures are being laid in terminal yards, while increased attention is being given to the selection of frogs and switches of smaller angles, so as to provide a greater margin of safety.

Wooden signs are fast being replaced with those made of concrete or iron and of more attractive appearance, while stronger types of woven wire fencing, with treated wood, steel or concrete posts, are being used to fence the right of way. Many wooden plank crossings are being relaid with other more lasting materials.

Water Stations.

The increased number of locomotives, and their greater size and power, the extending use of larger engine tanks as a means of accelerating train movement—these fre quently having capacities of from 16,0oo to 21,000 gal.—and the growing recognition of the value of improved quality of feed waters in promoting increased locomotive efficiency, has made the water an important factor among the other items of the fixed property. Railway water supply has become a highly specialized branch of operation, including at many plants treatment of the waters. The greater quantity of water required has made neces sary the installation of larger pumps and pumping combinations, while the need for uninterrupted service has shown the desira bility of ample storage capacity, with duplicate pumping units in some instances. Increased interest has been shown in the tur bine, among other deep wells and systems. While the steam plant predominates, the use of oil engines has grown greatly, and electric drive for pumps is advancing rapidly wherever current is avail able, particularly by reason of the advantages obtained through float switches, pressure gauges and remote control. Tanks for the

storage of water, which are of wood, steel and sometimes con crete, are of greater capacities, commonly as high as Ioo,000 gallons. Where track tanks are used to avoid delays due to stops for water, they are being lengthened to supply double-headed trains or those following each other at close intervals. While the essential features of the exterior treatment of locomotive waters has not changed greatly in recent years, and the precipitating and neutralizing of the harmful solids by lime and soda ash remain accepted practice, increasing use is being made of other chemicals to supplement this basic treatment. Definite progress has also been made in interior treatments by the development of new chemical compounds for introduction into the tender or directly into the locomotive boiler.

Passenger and freight stations, engine terminals, shops and powerhouses are essential to the operation of railways. (See the sections on Freight, Passenger and Water terminals for a dis cussion of these subjects.) The present design of track will continue substantially un changed for many years, although the economic advantages of heavy track construction will be increasingly appreciated and utilized. Advances will continue to be made in rails. Although the general use of the 150 lb. section is far in the future, its ultimate adoption is inevitable as wheel loads continue to in crease. Mill practice in the manufacture of rail will be further improved, providing enhanced wearing qualities with a reduction in failures. (E. T. H.)