.')(>! WOOD TRANSPORT BY LAND. 



must be done if they are to be at all permanent. If, instead 

 of merely spreading stones on the surface, the cart-track is 

 covered to a depth of 8 to 12 inches with broken stones which 

 are well rammed down, the road is said to be macadamised. 



In constructing forest-roads the greatest attention must be 

 paid to drainage, and this is of the highest importance in 

 plains and on peaty soil. In hill-roads, drainage is generally 

 secured by their sloping nature, especially on sunny aspects. 

 In order to drain roads on north and east aspects and on level 

 ground, side-drains must be kept open and the surface of the 

 road suitably curved. The road also must be raised above 

 the ordinary ground-level and well aerated by keeping it free 

 from over-hanging trees [although it is well-known that road- 

 side avenues are highly efficient drainers when the trees are 

 not too near the cart-track and are properly pruned Tr.]. 

 Where sufficient fall cannot be given to the side-drains, and 

 stone is not available, as in depressions on the plains, in 

 alder-woods, etc., every means should be taken for raising the 

 level of the road, and the ditches kept at some distance from 

 it so that the water in them may not permeate into the road 

 and make it soft. The draught of air is increased by keeping 

 the road straight, clearing broad road-sidings through the 

 forest and cutting away all overhanging trees. 



Macadamised roads have the great advantage over paved 

 roads, especially when gravel and small stones are at hand, of 

 being not only cheaper but actually easier for traffic than the 

 latter, except when very carefully constructed. 



(d) Paved Roads. Paved roads are distinguished from 

 ordinary roads by their greater width and the greater atten- 

 tion paid to the gradient, but especially by the care with 

 which they are metalled. The cart-track in them is excavated, 

 lined with stones or cement, and coarse broken stones arc 

 then spread on the surface and rolled down firmly. Several 

 other layers of stones are then superposed, each layer con- 

 sisting of finer material than the one below it. It is always 

 better to use broken stone, which packs bettor than round 

 pebbles. Each separate layer is rolled and firmly pressed 

 down. The more gradual the change of size in the material 

 used for successive layers of metalling, the more durable the 



