MEMOIR OF DANIEL TREADWELL, 



50 



The cars upon which the loads were placed were of the common form and size, the bodies resting 



upon springs. The wheels were 3 feel in diameter and the journals (gudgeons) 1£ inches in diameter. 



With this account of the apparatus, I shall prott d to give an account of six experiments made with 

 the engines before described. 



1. Friday, October 14, 1836. Experiment made with the Mercury, with the sparker on the engine, 



from the depot in Boston to Framingham, 20J miles. 



Load or Train. 



Tender No. 4, to which the dynamometer was attached from the first car. 



10 cars loaded with iron nails *\Y ight, 81,843 lb. 



1 car loaded with stone 9,210 



1 car loaded with some iron, and carrying apparatus and four persons 5,060 



Whole weight, 90,103 lb. 



One car was left at the ascent between the 11th and 12th mile, and is therefore accounted at 

 half its weight carried through. On the return the weight of the car is deducted, which leave* 

 the load on the return - 91,7951b. 



Out. 



Retu 



To 1 mile post 

 » 2 



44 



44 



ii 



u 



u 



44 



ii 



" 7 



a 



44 8 



a 



" 9 



a 



44 10 



44 



44 11 



44 



" 12 



44 



" 13 



44 



" 14 



44 



44 15 



44 



" 16 



44 



" 17 



44 



44 18 



44 



" 19 



44 



44 20 



44 



To Depot 



Framiu 



igham 



Time . . . . 



m. s. 



5 30 



4 30 



610 



662 

 490 



597 



3 15 



4S9 



3 45 



552 



4 15 



675 



12 15 



795 



6 30 



705 



2 45 



442 



3 15 



450 



4 30 



662 



4 45 



238 



3 15 



172 



3 10 



520 



3 35 



424 



2 



126 



91 15 



10,876 



1 31 15 



518 



To 20 mil 



le post 



4k 19 



44 



44 18 



ii 



44 17 



44 



44 16 



44 



44 15 



44 



44 14 



44 



44 13 



44 



44 JO 



44 



" 11 



44 



44 10 



44 



44 9 



44 



44 8 



44 



44 7 



44 



44 6 



44 



44 5 



44 



44 4 



44 



44 3 



44 



44 2 



44 



44 1 



44 



To Depot in 



Boston 





Time . 



it - 



Mi in 



irae. 



Draft, 



III. g. 



lb. 



2 45 



577 



3 15 



2» » 



2 45 



297 



3 15 



681 



3 40 



726 



3 15 



292 



3 5 







6 



610 



3 30 



276 



3 



60 



3 15 



96 



2 45 



3i:> 



2 45 



360 



2 40 



369 



3 25 



205 



2 40 



99 



4 5 



25 



2 45 



337 



3 



297 



20 



69 45 



250 



6.524 



9 45 310.6 



Remarks. 



Wind strong from the west, 

 or against the train, in its 

 coarse from Boston to Fnun- 



ingham. 



Engine stopped 8 minutes 

 between the 11th and 12th 



not draw 



load. 



mile, 



Uncoupled to turn out to get 

 water. Threw off one car, and 

 then the engine drew the re- 

 maining load up the plane. 

 The time of this stop deducted 

 from the whole time of pass- 

 ing from 11th to 12th mile. 



Wood 



used, being pine of ordinary quality. Out, 83 cubic feet, measured as ordinarily piled. Return, 60 

 cubic feet. The wood required to get up the steam not included in either case, either in this or the experiments 



afterwards made. 



Water used. Out, 53.4 cubic feet. Return, 42.5 cubic feet. 



Wood used to evaporate 1 cubic foot of water. Out, 1.55 cubic feet. Return, 1.41 cubic feet. 



The method pursued in noting the velocity and force of the draft, or traction, was as follows. An 

 assistant marked at every thirty seconds the place of the index of the dynamometer. The time of pass- 

 ing each mile-post was observed and set down by myself. These accounts were afterwards compared 

 together, and the mean force of the draft, as shown by the assistant's minutes, cast for each mile. The 



