8S A Letter to the Dublin SocUly 



height of three feet and a h.alf, or even eight feet above the 

 road. 



The distance between the fore and hinder axletrees in these 

 carriages was nine feet nine inches. 



These carriages were so made that eitlier of tl)em could be 

 shortened, so as to bring the hind and fore axletree within six 

 feet of each other. They were also so framed as to be stiflf and 

 strong in' every direction. Of tbese two carriages one had the 

 springs allowed to play, the other had not. 



cut. qrs. fh. 



The first was loaded with S 



Which, added to the weight of the carriage, made 17 



Tlie other 600 



Whicli, added to the weight of the carriage, made 15 



Both were connected with the peirameter, and the carriage 

 with springs, carrying the eight hundred weight, jjreceded the 

 other. To show that these carriages were similar to each other, 

 the springs of the former carriage were now prevented from 

 acting, and the carriage was loaded with 6cwt. 



The springs of the other carriage were then allowed to play, 

 and the carriage was loaded with 8 cwt. ; when the carriage pre- 

 ceded in the same manner as the first had done. 



The springs of both carriages were then made free, and the 

 axles of one of them brought within six feet of each other; the 

 other remaining at 7ii?ie Jeet 7iine inches asunder. The weight 

 of both was brought to an equality, and both were loaded at 

 lottom. 



cut. (]rs. lb. 



The carriage with the short perch was loaded with 6 

 The other with the long perch was loaded W'ith . . 5 2 



When put in motion they kept together. 



The load in the short perch carriage was then placed at the top. 



They both kept together. 



The springs of both were then prevented from acting. 



cwt. qrs. Ih. 



The short carriage had a load at top, . . ..600 

 The long carriage, loaded at bottom, . . ..530 



The long carriage rather preceded. 



These experiments were not performed under favourable cir- 

 cumstances, as the position of the hinder axletree in one of the 

 carriages had been accidentally deranged; but I beg leave here 

 to report the result of experiments which had been repeatedly 

 tried with great care at my own house. 



Both these carriages with the wheels at equal distances, and 

 the springs prevented from acting : one loaded at top, the other 

 at bottom. 



The 



J 



