Farm Roads on Strong Soils. 93 



It is not necessary to have the pieces uniform in size so long as 

 .the upper surface is regular and the whole firmly set. The hand- 

 laying of the stones will cost, on an average, three farthings per 

 square yard (see instance No. 6), 



Where neither native gravel nor rock is to be obtained, metalling 

 from a distance has to be imported by canal or railway for the 

 covering, and the total cost is much increased thereby. The writer 

 has constructed roads on the Oxford and lias clays, of which the 

 cost per chain has varied from 2/. 85. 4f/. to 5Z. 55. 6(/. In the 

 first instance clean native gravel, of excellent quality, and which 

 did not require sifting, was wholly used. In the latter the 

 metalling for the covering had to be obtained from a considerable 

 distance by canal, with a heavy cartage from the canal to the 

 road : burnt clay was used for the foundation. This substitute for 

 natural metalling is daily coming more and more into use through- 

 out the Gault, the Oxford, and the Lias clay districts. In these 

 clays the proportion of sand is generally less than in others, and 

 therefore a superior description of ballast is made. Coals, too, 

 are cheaper in the Midland and North-Eastern counties than in 

 the South-Eastern counties, and this fact has had its influence in 

 bringing burnt ballast more into use, and in making its manu- 

 facture better understood. 



The approximate cost per chain of the several descriptions of 

 roads suitable to the clay districts of the greensand, the oolitic, 

 and lias formations will be as follows : — 



No. 4. With unsifted gravel wholly. £ s d 



jPorma^iott (as detailed") IG 



Metalling, 9 inches deep, IG^ cubic yards, at -iid. per 



yard; digging and clamping 062 



Filling, at %l. per yard 02 1 



Carting I5 miles, at 10'7. per yard per mile 10 8 



Spreading, breaking, and finishing, at 2^d. per yard . . 3 5 



Total cost per chain .. ..' 2 8 4 



No. 5. With broken oolitic or lias rock wholly. £ s d 



J^o?-ma<iO/i (as detailed) 16 



Metalling, 9 inches deep, I62 cubic yards, at Is. ?)d. per 



yard ; quarrying, breaking, and clamping 10 8 



rilling, carting, spreading, and finishing, as No. 4 .. .. 16 2 



Total cost per chain 3 2 10 



