510 



MEMOIR OF DANIEL TEEADWELL. 



Following the previous method of fimling the resistance from frietion, the load being 111,300 lb., we have: — 

 Out. -^V^j'- ^ -09 lb. of the resistance sliown by the dynamometer from elevating the load. Mean draft, 



735.4 _ 209 = 526.4 lb. resistance from friction, and •'^j|.|'' = -68, or draft from friction ^th part of the load. 



Hence, 8.36 lb. required to draw one ton of 2:2i0 lb. 



Return, -i^f f^ = -09 lb., the tendency of the load to descend not shown by the dj-namometer. Mean draft 



as shown by dynamometer 446.8 -|- 209 = 6.3.5.8 lb. resistance from friction, and ^it%'^ = 51V i = ^Wz °'-' '^^'^^^ 



from friction when reduced to level jjj^ths of load. Hence 10.39 lb. required to draw 1 ton of 2,240 lb. 



6. Experiment made November 14, with the Lion, with the sparker ou the engine, from the depot in 



Boston to Framingham. 



Load ou Train. 

 Tender as before. 



12 cars loaded with rails Weight, 103,380 lb. 



3 cars loaded with stones and iron 33,2.36 



1 car loaded with apparatus and 2 persons 4.670 



Whole weight, 141,3u61b. 



Wood used, being pine of ordinary quality. Out, 67 cubic feet. Return, 44 cubic feet. 



Water used. Out, 53.42 cubic feet. Return, 43.35 cubic feet. 



AVood used to evaporate one foot of water. Out, 1.25 cubic feet. Return, 1.01 cubic feet. 



Following the former method of finding the resistance from friction, the load being 141,306 lb., we have : — 



Out. ^'^*^ = 209 lb. of resistance shown by dynamometer from elevating the load. Mean draft, 

 685 — 209 = 476, resistance as reduced for a level, and 1^,^^ = 290.8; or draft when reduced to a level 

 ■j^^ths part of the load. Hence, 7.55 lb. required to draw one ton of 2,240 lb. 



Return. ■^VtV''^ = -'^^ ^^-i ^^^ tendency of the load to descend not shown by the dynamometer. Mean draft 

 shown by dynamometer 387 -|- 209 = 596 lb. resistance from friction, and ' '^^\" ^ = 237 ; or draft when reduced 

 for a level ^^th part of load. Hence 9.45 lb. required to draw one ton of 2,240 lb. 



Note. — Calculating in the ordinary mode from the mean traction during the p.as.sage up the road, we find the engine 

 a 25 horee-power. From the experiments up and down, it appears that the load 63 tons would be drawn over a level 20J 

 miles with 60 cubic feet of wood. Cost at §6 a cord, §2.81. Then one ton drawn over a level one mile at an expense for wood 

 of 2}th mills. 



