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I have caused several experiments to be made on the fair working 

 powers of the horse. It is well settled by English authorities that the 

 strength of a horse is equal to a strain of 200 lbs., at a working speed 

 of two and a half miles an hour, or, in other words, of raising 200 lbs. 

 This may be more readily appreciated when it is also understood that 

 the strength of jive men is equal to that of one horse — thus establishing 

 ' the strength of each man at 40 lbs. of power. I employed a competent 

 engineer, (E. Willard Smith, now Engineer of the Chicago Water 

 Works,) to test the force of traction by actual experiment. He reported 

 the result to be as follows : 



"I have tried the experiment on the power of traction upon the State 

 Street Bridge, Albany. I had an ordinary dirt wagon loaded with 

 sand ; the wagon and load weighed 4,650 lbs. I placed the load on 

 the centre span of the bridge, which is level, then took up a plank of 

 the floor, and over the opening fixed a pulley, over which we passed a 

 rope attached to the wagon, and fastened a weignt of 120 lbs. to the 

 end. This weight kept the load in motion after it was started. Ac- 

 cording to this result, a force of traction of 1 00 lbs. will move on a 

 level plank road, 3,650 lbs. English authors state that 100 lbs. will 

 move 1,800 lbs. on a Mc Adams road. A day or two after this experi- 

 ment on the bridge, I tried the same experiment on a hard eai-th road ; 

 the result was, 100 lbs. moved 1190 lbs. This makes 100 lbs. on a 

 plank road, move three times as much as on an earth road — but as 

 this earth road was much better than the average of common 

 earth roads, it may be safely stated that the result is, as four on plank 

 roads to one on common roads. 



On plank roads, 100 lbs. move 3,650 lbs. 



McAdara do do do 1,800 " 



Common earth road, do 1,1 90 " 



I cannot find that either of the experiments have before been tried, 

 and the result is very satisfactory. 



Authors say that a horse can exert or draw with a force of 200 lbs., 

 at the rate of two and a half miles per hour; therefore, a pair of horses 

 would draw 7 tons on a level plank road, including weight of wagon. 

 The wagon I used on the bridge was a rough one, and not well greased. 



In a subsequent report by the same engineer, he says : 



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