LOCOMOTIVE ERECTING SHOP, PHILADELPHIA & READING R. R. 377 



The sidewalls and bottoms of the pits are made of cement concrete 

 of the composition already described as being employed in the founda- 

 tions for the main columns, Fig. 180, and have a facing of I in. of cem- 

 ent. It will be noticed that the bottoms of the pits are crowned trans- 

 versely and have longitudinal side drains of "catch basin" type, run- 

 ning into gutters which connect with the tile drain pipe system of the 

 building. The pit rails are carried on 10 x 12-in. yellow pine side tim- 

 bers resting on the concrete pit walls and connected By anchor rods 

 extending into the bituminous concrete floor foundation. The railway 

 tracks in the building consist of 8o-lb. rails spiked to cross-ties laid in 

 stone ballast. 



Before taking up the exterior construction of the building, a brief 

 reference may be made to the method adopted for heating it. By re- 

 ferring to Figs. 176 and 177 it will be noticed that an underground duct 

 extends along each side of the buildings. This duct will contain all the 

 steam, air and other piping entering the building and will also serve as 

 a hot-air duct for heating the building. For the latter purpose the duct 

 connects with fan houses placed at intervals along the side of the build- 

 ing, there being four fan houses on the west side and three on the east 

 side. It is expected that the exhaust steam will be ample to heat the 

 building. The general principle of the operation of the heating appara- 

 tus is to use the air over and over again, depending upon the natural ven- 

 tilation to keep it fresh. Structually the ducts are simple, their bottoms 

 and side walls being of concrete with a cement plaster, and the roof be- 

 ing expanded metal and concrete supported by transverse roof beams. 

 The roofs of the fan houses will consist of I beams carrying T-iron 

 purlins holding book tile, which in turn carry a felt and slag roofing 

 similar to that already described for the main building. 



From the structural point of view, the wall construction of the 

 main building presents nothing that is particularly notable. These walls 

 are of brick masonry resting on a concrete footing and are anchored to 

 the wall columns, as shown by Fig. 178, but they are independent struc- 

 tures, receiving no support from these columns. The entire wall area 

 is pretty well taken up with doors and windows, there being one in each 

 panel or between each pair of wall columns. This introduces a con- 

 siderable amount of arch work, but nothing that is of unusual character. 



To illustrate the simple methods which have been adopted to secure 

 a pleasing exterior appearance for the building, the typical details of 

 the wall construction are shown in Fig. 179. 



