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suitable depth, and preparing the form for the pave- 

 ment with the precautions as for a common pavement. 

 Blocks of stone of an irregular pyramidal shape are 

 selected for the pavement, which, for a road-way thirty 

 feet in width, should be seven inches thick for the cen- 

 tre of the road, and three inches thick at the sides. 

 The base of each should not measure more than five 

 inches, and the top not less than four inches. 



"The blocks are set by the hand, with great care, as 

 closely in contact at their bases as practicable ; and 

 blocks of a suitable size are selected to give the surface 

 of the pavement a slightly convex shape from the centre 

 outwards. The spaces between the blocks are filled 

 with chippings of stone, compactly set with a small 

 hammer. 



"A layer of broken stone, four inches thick, is laid 

 over this pavement, for a width of nine feet, on each 

 side of the centre ; no fragment of this layer should 

 measure over two-and-a-half inches in any direction. 

 A layer of broken stone of smaller dimensions, or of 

 clean, coarse gravel, is spread over the wings to the 

 same depth as the centre layer. 



"The road-covering thus prepared, is thrown open 

 to vehicles until the upper layer has become perfectly 

 compact, care having been taken to fill in the ruts with 

 fresh stone, in order to obtain a uniform surface. A 

 second layer, about two inches in depth, is then laid over 

 the centre of the road-way ; and the wings receive also 

 a layer of new material laid on to a sufficient thickness 

 to make the outside of the road-way nine inches lower 



