476 NEW COMPOUND RAIL, 



It is evident that the joints of these rails, forming as they do a series 

 of long scarfs, must be very much stronger and better than the com- 

 mon chair joints, but still the joints are not so strong as the body of 

 the rails, since at the points where they occur one half only of the 

 sectional area of the rail is solid. If there had been no other objec- 

 tion to these compound rails than the absence of as much strength at 

 the joints as elsewhere, they would, no doubt, be more generally in 

 use than we find them, inasmuch as in them the weak and defective 

 part of the common rail is very materially remedied. Experience, 

 however, has demonstrated that all these patterns of rails are open to 

 serious objections, the most important of which may be stated as being 

 increased first cost over the common rail, excessive cost of mainten- 

 ance, and too rapid wearing out. 



It is evident that these objections may readily be attributed to the 

 plan of construction, as the application of bolts or rivets throughout the 

 entire length of the rail is indispensable to hold the two halves together. 

 As already explained, bolts cannot be relied on, inasmuch as they con- 

 stantly shake loose, and in this state the stability of the rail is 

 impaired. It is found, too, that rivets for other reasons are perhaps 

 even more objectionable, and whether bolts or rivets are used it is 

 not long before laminated portions of the upper surface of the 

 rail get in between the two plates, and these acting like small wedges, 

 and driven tight by every passing train, gradually open up the 

 rail and hasten its destruction. It is found, moreover, that unless 

 the bolts are properly performing their duty, the whole weight 

 of trains not unfrequently comes on a single half of the rail, produc- 

 ing violent strains which soon tell on the durability of the several 

 parts. For these reasons such compound rails as have been already 

 tried have not proved economical in maintenance, and in consequence 

 have fallen into disuse. 



The design of the compound rail now submitted may be executed 

 of any required weight which a heavy traffic might demand. It is 

 thought, however, that a good serviceable rail may be made weighing 

 80 lbs. per yard including wrought iron cores, the cores themselves 

 weighing 25 lbs., and each half of the rail 36|^ lbs. The ties could be 

 grooved by a machine at a trifling cost, and the grooves for both rails 

 could be cut at the same operation ; by this means the proper guage 

 of the track would be permanently secured, and the whole superstruc- 

 ture would be laid with the greatest ease and with very little skilled 



