BROKEN STONE COVERINGS. 299 



when the whole should be thoroughly consolidated with rollers 

 of five or six tons weight. If then the drainage is properly at- 

 tended to, the roads will become nearly equal to the best, and 

 with watchful care, may be kept permanently so, with small cost, 

 in comparison to the present outlays for patching and repairs. 

 A saving might be made by putting on both layers unscreened, 

 but the road would not be so perfect or durable ; besides this, the 

 greater ease and comfort of travel upon the screened gravel, and 

 the difference of wear would doubtless repay the cost of screen- 

 ing. 



Upon places where the old road is not sufficiently firm — being 

 either sandy or loamy — a foundation of rubble-stone may be laid 

 to the depth of eight or nine inches. The stones used for this 

 purpose should be angular, having no dimensions greater than 

 twelve inches or less than three inches, and should be carefully 

 and closely laid together, the longest way across the road. 



The surface should then be evened by spreading stone chips 

 over it, when the gravel may be put on and treated as described 

 above, except that an additional layer will be needed to guard 

 against a movement among the loosely deposited stones below. 



When the roads are already in tolerable good condition, with 

 a good gravel surface, nothing more perhaps will need be done 

 than to dress them into proper shape and to fill the hollows and 

 even the surface. If however the surface is much worn into ruts 

 and hollows, or the gravelly coating has become thin, a layer of 

 two or three inches of screened gravel should be spread evenly 

 over the whole of it and rolled solid. 



In situations where gravel of suitable quality cannot be ob- 

 tained, or upon roads much frequented by heavily loaded teams, 

 broken stone must take its place in the work of renovation. In 

 such cases the surface of the road must be newly shaped, in the 

 same way as for gravel, taking care not to break it to a greater 

 depth than just sufficient to give it the proper form and to 

 make it even. The manner of applying this material to the old 

 joad-beds is the same as has already been described. 



In all cases, the mode of proceeding and the precautions to 

 be taken are the same for the old roads as for the new. Wher- 

 ever the travelled part of the road is not of sufficient width, it 

 should be made so before being coated with surface-materials, 



