14» 



ON DRAUGHT. 



JONES S PATENT WHEEr,. 



Fi'T 37. Fie. 38. 



Willi respect to the size of wheels, we have shown that wheels of large 

 diameter certainly offer less resistance than small ones ; but expense and 

 weight cause a limit to this. From 4 ft. 9 in. to 5 ft. 6 in. is a good size 

 for cart-wheels, and is about the limit where any great increase of diameter 

 would cause more inconvenience and expense than would be compensated 

 for by any advantage gained, and if much less in diameter than this, the 

 draught is unnecessarily augmented. 



Yet the front wheels of a waggon are always below this standard, rarely 

 exceeding four feet, and frequently much less. This is a serious evil 

 attending the use of four wheels, it is an arrangement originally made for 

 the purpose of enabling the front wheels to lock under the body of the 

 waggon, which may thus turn in a small space. 



Now it rarely happens that a waggon is required to turn short round, 

 and it cannot cause any serious inconvenience if it be rendered altogether 

 incapable of doing so. 



In this i-espect a great improvement has taken place within a kw years. 

 In the place of those moving mountains which were formerly dragged 

 slowly along upon immensely heavy and broad, but low, wheels, ve now 

 see, particularly on the roads leading northward from London, a great 

 number of light, well-built waggons, with much larger wheels, especially 

 the Iront wheels, which, instead of being small enough to turn under the 

 floor of the waggon, are about four feet six inches in diameter. As those 

 waggons are used only on the road, and are never required to turn in 8 

 small compass, but a very small action is allowed to the fore-axle, and the 

 floor and body of the waggon is continued from end to end of nearly the 

 same width. 



