RAILWAY CONSTRUCTION. 53 



sleepers. This method is not nearly so strong or efficient as 

 the arrangement shown on Fig. 33, with a cast-iron distance- 

 block about six inches long, placed between the running-rail and 

 check-rail, and all tied together with a strong through bolt. A 

 bolt-hole is punched in the edge of the flange of check-rail, and 

 a crab bolt and clip holds the two rails on the sleeper. The cast- 

 iron distance-blocks are placed just outside the sleeper, so as not 

 to interfere with the holding-down bolt. Doubtless these 

 guard rails do good service, but if the leading wheels of the 

 engine have sharp or worn flanges there is the possibility that 

 the wheel, pressing against the high rail, may mount the rail, and 

 throw the train off the line. A more secure method is to place 

 the guard outside the high rail, as in Figs. 34 to 38. This can 

 be done by securing a strong continuous longitudinal timber to 

 the cross-sleepers or to the cross-girders in the case of a girder 

 bridge with its outer or striking edge protected with a fairly 

 heavy angle iron. The top of this outside guard above the rail 

 level may be three inches or more, according to the height of any 

 hanging spring, or portion of brake apparatus belonging to the 

 rolling-stock. The distance between the striking-face of the guard 

 and the inside of head of rail should be about 5 inches, or such 

 width that before the flange of the wheel can mount on the top of 

 the rail, the face of the wheel-tyre will be brought into contact 

 with the striking-face of the outside guard, and thus effectually 

 prevent the wheel leaving the rail. The sketches show some of 

 the types applicable to the chair road, and to the flange railroad. 

 In Figs. 34, 35, and 37, the outside brackets are of heavy angle 

 iron cut off in lengths to correspond to the width of the sleeper. 

 In Fig. 36 the cast-iron chair is lengthened, and has an end 

 bracket to support the guard timber. In Fig. 37 a hard wood 

 bolster is fastened on the top of each sleeper, and on this is 

 placed the continuous guard timber. This method of increased 

 security is frequently adopted on girder bridges and long iron 

 viaducts which are on the straight, and in such cases it is 

 usual to place the guards outside each of the rails forming the 

 track. 



The introduction of bogie engines and bogie carriages has 

 conduced largely to the safe working of the train-service over the 

 curved portions of many of our home railways, as well as to the 

 economy in the wear and tear of permanent way and rolling- 

 stock. The action of long rigid wheel-base vehicles passing 



