320 ANNALS OF THE ROAD. 



over the other end of it ; and secondly, by presenting an 

 obstacle, which is to be surmounted, the wheel falls with 

 increased force from the top of that obstacle, and conse- 

 quently makes a hole in the road. If an iron hammer 

 were constantly to glide over an iron surface, neither of 

 them would feel the effect for a very long series of years ; 

 but only let there be an obstacle for the hammer to sur- 

 mount, and drop thence on the iron, the consequence 

 would very soon be destructive to both. 



Although philosophers have been long since aware 

 that ice is formed by the spicules uniting by their own 

 angles, yet it remained for Mr. M'Adam to put to the 

 proof the fact of stones forming an equally firm surface 

 by the uniting of their angles. Such, however, is the 

 case : and where the material is of good quality, many 

 barn floors, on which corn is thrashed, are not so even 

 and so hard as some of our turnpike roads. One other 

 great advantage attends them. When once they bind, 

 there is no obstacle work for the wheels on level ground ; 

 neither is it necessary to round the roads in the middle, 

 from which form several accidents to coaches have arisen ; 

 and I do not think our night coaches could go the pace 

 they now do, with roads rounded in the centre. 



The worst material we have for roads is gravel. 

 Upon gravel roads, to use the language of a coachman, 

 there is no life in the coach, but the wheels are always 

 crying out, and on level ground the horses never have a 

 slack trace. Stone is now brought from a great distance, 

 where water carriage is to be had, to many roads in the 

 neighbourhood of which crave! abounds. 



