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Introduction to the Study of Science 



The Erie locomotive works 

 as a "pusher" on a long, 

 heavy grade. Its weight is 

 853,000 pounds, with a wheel 

 base of 90 feet and a total 

 length of 105 feet. Its direct 

 pull on the drawbar, or tractive 

 effort, is 160,000 pounds. It 

 has moved a train of 250 loaded 

 cars of fifty tons' capacity each, 

 making a total load of about 

 18,000 tons, at a speed of 15 

 miles an hour. It is capable of 

 moving a train of 640 loaded 

 cars with a total weight of 

 45,000 tons, and nearly five 

 miles long. The most power- 

 ful engine prior to this has 

 about two thirds the tractive 

 effort, or 115,000 pounds, and 

 can push a train of about 

 30,000 tons. 



The Erie locomotive is of 

 the Virginian Mallet type, 

 compound, and made up of 

 three sets of engines with 

 three pairs of cylinders, each 

 pair driving a group of eight 

 wheels coupled, each wheel 

 being sixty-three inches in 

 diameter. Fuel is supplied 

 by a mechanical stoker at the 

 rate of at least one hundred 

 pounds per minute. The cyl- 

 inders are thirty-six inches in 



