MEANS OF TRANSPORT. 



advantage of diminished weight for the man, 

 when there is no passenger. It appears that 

 this might be accomplished by attaching the 

 shafts in such a way that they could be made 

 to slide in the axle-frame. If the seat body 

 were one-fourth of the weight of the man, it 

 would require four times the leverage to balance 

 him ; and with twice the leverage it would 

 balance half his weight. When there is no 

 passenger, let the seat be made to slide back- 

 wards, as shown in Fig. 2, till it is three times 

 as far from A to C as from B to C. Then the man 

 can lean three-fourths of his weight on the shafts, 

 in other words relieve his legs of three-fourths 

 of his weight, even when there is no passenger, 

 and without adding to the total weight to be 

 lifted, against gravity, when going up-hill. 



2. When a Train is going at Sixty Miles an Hour, 

 what Part of it is moving backwards ? 



That is, not relatively, but actually back- 

 wards. For when an express train is advancing 

 at the above rate, there are always some small 

 portions of every carriage, as well as of the 

 engine and tender, that are actually moving 

 backwards at the rate of something like ten 

 miles an hour. 



How does this come about ? 



Take a circular disc, such as a penny piece, 

 draw a line, such as A C (Fig. 3), from the 



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