3Q 



THE GUIDE TO NATURE. 



THE LARGEST LOCOMOTIVE. 



ed just ahead of the high pressure cyl- 

 inders. They are designed for pusher 

 service and will operate on the Susque- 

 hanna Hill between Susquehanna and 

 Gulf Summit, where the ruling grade is 

 1.3 per cent. The total weight in work- 

 ing order of each of these locomotives is 

 about 410,000 pounds. Each locomo- 

 tive has sixteen driving wheels, arranged 

 in two groups of 8 coupled wheels. The 

 high pressure cylinders which drive on 

 the rear group of wheels are 25 inches 

 in diameter by 28 inches in stroke, and 

 the low pressure cylinders are 39 inches 

 in diameter by the same stroke. With a 

 boiler pressure of 215 pounds and driv- 

 ing wheels 51 inches in diameter, these 

 engines will develop a maximum tract- 

 ive power, working compound, of 94,- 

 800 pounds and 116,000 pounds, working 

 simple. This means that one of these 

 locomotives will haul 210 cars. 



The boiler is the largest locomotive 

 boiler ever built, and is of the radial 

 stayed type with conical connection. The 

 inside diameter of the first or smallest 

 course is 82 inches, while that of the 

 largest course is qf> inches. The plates 



are, of course, all very heavy, the heav- 

 iest ring of the shell being 1 1-16 inches. 



The engines are compounded on the 

 Afellin system which has been so success- 

 fully employed on a great many two-cyl- 

 inder compound engines ; and their oper- 

 ation, therefore, is exactly the same and 

 as simple as that of a compound loco- 

 motive with half the number of cylinders. 

 By an ingenious arrangement of the re- 

 versing gear, the weights of the valve 

 motions of the front and rear engines 

 counterbalance each other. The reverse 

 lever is operated by compressed air cylin- 

 ders by means of an auxiliary lever 

 which controls the valves in the air cyl- 

 inders. 



While the hauling capacity of these 

 enormous engines is more than double 

 that of the heaviest freight engine now 

 in service on the road, the load on any 

 single pair of driving wheels is less than 

 that of many of the ordinary road engines 

 of the present day. In view of this fact, 

 the advantages offered by this type for 

 the concentration of power in a single 

 unit are readily recognized. — Courtesy of 

 Erie R. R. 



EDAGOGICAL 



This department has been unavoidably omitted from this issue. 



