170 



ME. WILLIAM FAIEBAIRN ON THE 



assistant engine, is 23"5 tons, at 19'8 miles an hour; whereas, 

 in taking the mean of seven experiments with the leading 

 engine alone, we find that nearly the same weight is raised 

 at about the same velocity, or 20 tons at 20 miles an hour ; 

 and, what is still more extraordinary, on March 6th, a load 

 of 25 tons is raised to the top of the incline at the rate of 

 20 miles an hour by the single engine. 



TABLE X. 



PASSENGER TRAINS. 



The duty performed respectively by the engines is 

 nearly equal in this Table, and will compare with the trips 

 in Tables VIII. and IX., which, taken in the aggregate, 

 indicate nearly the same results, with the exception only of 

 the performance of the single engine in Table IX., which, 

 as before noticed, greatly exceeds the duty of the double 

 -engines. 



