CONSTRUCTION OF WALLS, &C. I'td 



should be constructed, brick is certainly the best ; 

 that is, for the superstructure. Stone is best for tlie 

 foundation and basement. Bricks give more warmth, 

 and answer better for training trees to, than stone. 

 South, east, and west aspects, should therefore be 

 faced with brick, if the wall be not entirely built 

 of it. If the wall be built entirely of stone, or be 

 backed witli stone and be faced witli bricks, and if 

 trees are to be trained against such backing, the 

 stones should be run in regular courses of from four 

 to seven or eight inches thick, and each fifteen or 

 twenty inches in length, by which there may be a 

 frequency of joints, and that the trees may be pro- 

 perly trained against the wall. 



Dark-coloured whinstone * is the next best ma- 

 terial to brick, (wlicn properly squared and ham- 

 mer-dressed), as it absorbs heat; and next to that, 

 a kind of bluish-grey stone, t that rises in natural 

 flags, the thickness, or nearly the thickness, of 

 bricks, and which require but little dressing, or 

 trouble in building. The nearer the stone approach- 

 es to black, the more valuable it is for the purpose j 

 the preference being given to tlie darkest whinstone, 

 merely because it absorbs and retains heat more 

 than light-coloured stones, and, by reason of its close 

 texture or grain, repels moisture better, or retains 

 less of it than other stones. 



But good durable freestone, being properly square 



* Greenstone and Basali of mineralogists. 



f Sandstone-Jlng; or, in parts of the country consisting of 

 primitive rocks, Clay-slate. 



