AMERICAN INSTITUTE. 



665 



upper edge of the frame, with the gravel employed in filling the 

 whole to the surface, secure a good foothold for the horse. The 

 advantages of this pavement are economy in wear and tear, great 

 facilities for removal and relaying, absence of dust in summer, 

 not slippery in winter, and not productive of much noise. 



In constructing roads, or streets, through cities, where there is 

 much traffic, it will be found necessary to pave them with wood, 

 iron or stones. The advantages of these materials over Macadam- 

 ising are great. When the latter are exposed to much traffic, 

 they become rutty, and require constant repairs at great cost; 

 then again in dry weather they are excessively dusty, and in wet 

 weather muddy. The only advantage that it seems to possess 

 over stone or iron is, that less noise is produced by wheels 

 upon it. 



In estimating the cost of maintaining a Macademised road, I 

 have concluded that the entire superstructure would necessarily 

 have to be renewed annually, the cost of which renewal would 

 be about five shillings the square yard, which is more than double 

 that of making and keeping in repair a paved street, without 

 taking into consideration the extra cost of cleaning a Macadam- 

 ised road, which is great, from the fact that hundreds of tons of 

 stone material are annually ground to dust by the travel, and 

 must be removed. These roads are much used in Great Britain, 

 and are superior to those made in the same way in other coun- 

 tries, from the fact that she has a great abundance of materials 

 admirably adapted, and their ground is firm, being chiefly com- 

 posed of sand, gravel and flint; consequently the water filters 

 readily through it, and leaves the road comparatively dry imme- 

 diately after rain. Then again, notwithstanding their climate is 

 habitually damp, they are not subject to the heavy torrents of 

 rain, which causes such immediate destruction to the roads of 

 other countries, and particularly ours. Still, if we adopt Mac- 

 adam's rule, and form a strong, smooth and solid artificial 

 flooring, capable of carrying great weights, and over which 

 vehicles can pass without meeting any impediment, they will 

 stand the storms. 



