Wheels with Broad Felloes. 677 



I know very well that wheels with conical felloes or 

 tires have one disadvantage ; for I was present at the 

 ingenious experiments of Mr. Cummings, which made 

 the fact evident. (See Annales des Arts et Manufact- 

 ures, Vol. v., p. 88.) This disadvantage, however, — 

 that of grinding the road, — would be hardly sensible 

 in wheels 4 feet high, with felloes only 4 inches broad. 



A carriage set on wheels with broad felloes, which 

 turn on a nearly straight axle, will be much less liable 

 to be overturned than ordinary carriages ; and this is 

 assuredly a very important advantage, especially in a 

 travelling carriage. Nor, on the other hand, will the 

 carriage be more likely to get locked with another, on 

 account of this change ; for the considerable inclina- 

 tion which is now given to the hind wheels causes these 

 wheels to be farther apart above than the new wheels 

 on a suitable axle would be. 



As to the exact width which would be the most ad- 

 vantageous for wheels intended for pleasure carriages, 

 that experiment alone can determine. It will be 

 necessary to find it by trial, as I have sought to do. I 

 know for a certainty that wheels 4 inches broad are pref- 

 erable, in all respects, to those which are only 2\ inches 

 in breadth ; but it is quite possible that a carriage 

 mounted on wheels 3-3- inches in breadth would be as 

 easy, or almost as easy, as mine on my new wheels. 



As long as the tires are broad enough to prevent 

 the wheels sliding from side to side, and tumbling 

 into the spaces between the stones of the pavement, 

 the carriage will roll very easily. 



I found that my carriage became perceptibly easier 

 with my last wheels, which were 2\ inches wide, than 

 it had ever been with the preceding ones, which were 



