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REPORT — 1841. 



Upon a general view of the body of experimental researches which have 

 been detailed in this Report, the following practical conclusions appear to be 

 fully established : — 



1 . The resistance offered to the moving power by a railway train is not, as 

 has been heretofore supposed, independent of the speed, but is augmented in 

 a high proportion as the speed is increased. 



2. If the carriages be unaltered in number, form, and magnitude, the re- 

 sistance will be in the simple ratio of the load, the speed and other circum- 

 stances being the same. 



3. If the train be increased by augmenting the number of carriages, the 

 ratio of the resistance to the weight at the same speed, other things being the 

 same, will be diminished. 



4. The practice hitherto adopted of expressing the resistance on railways 

 as so man^ pounds per ton of the gross load ought to be discontinued, since 

 the resistance is not proportional to the gross load, and therefore such ex- 

 pression may lead to erroneous conclusions. 



5. The resistance of ordinary loads transported on railways at ordinary 

 speeds, more especially of passenger trains, is very much greater than has 

 been heretofore assumed, being with heavy loads at least double the common 

 estimate, and with light loads threefold greater. 



6. That a considerable amount of the resistance, more especially in the 

 case of passenger trains, is due to the resistance of the air, and therefore 

 expedients (such as wheels of increased magnitude) to diminish the amount 

 of the mechanical resistances are not likely to be attended with adequate 

 advantage. 



7. That the resistance due to the air appears to proceed from the effect of 

 the entire volume of the train, and not to depend in any sensible degree on 

 the form of its foremost end. Expedients, therefore, for attaching a sharp 

 front to the engine are ineffectual and useless. 



8. That the mathematical formulae given in the first part of this Report, 

 consisting of two parts,^ — one proportional to the gross weight of the load but 

 independent of the speed, and the other proportional to the square of the 

 speed — have given results in all the cases to which they have been applied 

 in accordance with the experiments. Such formulse may therefore be taken 

 to represent the facts until further and more extended and varied experience 

 shall show the corrections of. which they may be susceptible. 



9. That the resistance produced to railway trains moving at ordinary speeds, 



