CHAP. XT. TELFORD'S ROAD CONSTRUCTION. 429 



works were placed under Mr. Telford's charge ; and 

 an admirable road was very shortly under construction 

 between Carlisle and Glasgow. That part of it be- 

 tween Hamilton and Glasgow, eleven miles in length, 

 was however left in the hands of local trustees, as was 

 the diversion of thirteen miles at the boundary of the 

 counties of Lanark and Dumfries, for which a previous 

 Act had been obtained. 



The length of new line constructed by Mr. Telford 

 was sixty-nine miles, and it was probably the finest piece 

 of road which up to that time had been made. The 

 engineer paid especial attention to two points : first, to 

 lay it out as nearly as possible upon a level, so as to 

 reduce the draught to horses dragging heavy vehi- 

 cles, one in thirty being about the severest gradient 

 at any part of the road. The next point was to make 

 the working, or middle portion of the road, as firm and 

 substantial as possible, so as to bear, without shrinking, 

 the heaviest weight likely to be brought over it. With 

 this object he specified that the metal bed was to be formed 

 in two layers, rising about four inches towards the centre 

 the bottom course being of stones (whinstone, lime- 

 stone, or hard freestone), seven inches in depth. These 

 were to be carefully set by hand, with the broadest ends 

 downwards, all crossbonded or jointed, no stone being 

 more than three inches wide on the top. The spaces be- 

 tween them were then to be filled up with smaller stones, 

 packed by hand, so as to bring the whole to an even and 

 firm surface. Over this a top course was to be laid, 

 seven inches in depth, consisting of properly broken hard 

 whinstones, none exceeding six ounces in weight, and 

 each to be able to pass through a circular ring, two inches 

 and a half in diameter ; a binding of gravel, about an 

 inch in thickness, being placed over all. A drain crossed 

 under the bed of the bottom layer to the outside ditch in 

 every hundred yards. The result was an admirably easy, 

 firm, and dry road, capable of being travelled upon in 



