40 



GARDEN MANAGEMENT. 





about 2 feet, and through the clay subsoil, R S, about 30 inches. A A A are 

 pieces of flat stone, two on each side, supporting the 

 horizontal one : over it is laid a layer of round 

 stones, B, over which the soil is replaced. In ji(]. B 

 is another form of drain, suitable for retentive soils. 

 The construction is the same : two stones or tiles, 

 placed at right angles, rest against the sides, and a 

 third is placed horizontally over them ; the soil is 

 replaced, the looser parts being at the bottom. In 

 fig. C we have the most perfect of all drainarre : a 

 circular drain-pipe, C, is laid at the bottom o'f the 

 trench ; over it are laid, first, the roughest rubble, B, 

 available,— a slate or tile, a, laid across over the 

 rough stones will prevent roots penetrating to the 

 pipes, as well as the earth from falling in through the 

 stones. In fig. D we have the arrangement which 

 Mr. Chitty considers the most convenient, especially 

 for porous soils. A serviceable fiat tile or sole is laid 

 flat in the bottom of the open trench, resting on a 

 sohd and perfectly level bed, gently falling from the 

 higher ground to the outflow ; over the tile is laid a 

 semicircular tile, forming an arch extending uninter- 

 ruptedly along the length of the drain ; over this is 

 thrown a layer of rough stones and rubble, 6 or 8 

 inches thick ; over this a tile, to keep out sand, roots 

 ot trees, and other destructive agencies ; and over the whole the surface-soil is 

 agam filled in. We have to add that in/.^. C, our artist has failed tosink the 

 dram mto the substratum R C. The consequence of such an error in practice 

 is explained in para. 9S. 



105. In laying down a system of drainage, the chief attention is required 

 to the surface of the ground.-Is it level or undulating? Is it commanded 

 by neighbouring heights? The next consideration is the question of 

 outfall. Let us imagine an area of say ten acres and a half, which is to 

 become the site of a house and range of gardens, of which the accompanvin- 

 IS a sketch. Its southern boundary is a river flowing from west to east or 

 nearly so. On the eastern extremity rises a gentle hill, sloping off towards 

 the river,-light sandy soi) with clay subsoil. Beyond it a brook di-ains its 

 eastern slopes, flowing into the larger river a little to the eastward- to the 

 north, this hill inclines slightly to the west. On the west rises a similar hill 

 the profile of which is seen in the cross section, RS : this height rises rather 

 abruptly from the river, slopes off towards the north, but rises again, the 

 heights running nearly parallel to the eastern range, leaving a gentle undu- 

 lating valley between them, sloping off towards the river ; a site, it will be ob- 

 served, of great capabilities in a pictm-esquc point of view, when it is laid out as 

 gardens and filled up with trees. 



'J~^ P LlO 



