CHAP. LXIX. 



1175 



sists solely of beds and gravel walks, as is 

 sometimes the case ; but they are peculiarly 

 applicable where the general surface is of 

 turf, even if that surface should not be level. 

 The opening of these surface drains need 

 not be more than 2 in. wide, and 6 in. deep, 

 formed of bricks, laid on edge for the sides, 

 and flatwise for the bottom and top, as shown in fig. 999. The upper 

 surface of the covering bricks of this drain should be level with the sur- 

 face of the lawn ; and, as the covers would be laid on alternately crosswise 

 and lengthwise, the appearance would be as in fig. 1000. The upper sur- 

 face of the bricks, being exposed to the air and weather, 

 would soon assume a dingy colour, so as to harmonise 

 with the green of the turf; and, being as perfectly even and 

 smooth as the ground on each side, they would offer no 

 obstruction to walking, rolling, or mowing. The brick* 

 work of the drain should be formed without mortar, in 

 order to let the water escape at the bottom and sides; 

 and to admit of taking off the top bricks to clear out any 

 fibrous roots, or any other obstruction that might be formed 

 in it. If the appearance of the bricks were thought a de- 

 formity, the brickwork might be sunk 3 in. deeper, and 

 covered with turf; and, if the expense of bricks were an 

 object, it might be lessened by employing earthenware pipes, 

 of small diameter, not cementing them at the joints, or 

 using draining or ridge tiles, and setting them on common 

 flat tiles, and covering the whole with soil and turf, so as not 

 to show any appearance of a drain on the surface, as shown 

 in fig. 1001. Drains of this kind are not adapted for being 

 laid out in parallel straight lines in ericacetums, because 

 these lines would necessarily interfere with the dug groups ; 

 but they are well adapted for being carried in irregular lines 

 in the glades of turf between the beds ; and they may be 

 supplied with water at one or both ends. Even an ericace- 

 tum, or other garden or lawn, on an irregular surface, may be 



1000 



watered in this way, on the principle on which surface irrigation is practised on 



hilly ground ; viz. beginning on the highest spot, and winding the drain about, 



always with a certain degree of steepness, 



till the lowest ground is reached. The 



whole of any lawn or park, however irregular 



it might be on the surface, might be kept 



moist in this way during the hot summer 



months, without a drop of water being ever 



seen upon the grass. 



Another mode of supplying water to an 

 ericacetum is by simply flooding the sur- 

 face, which, being on a perfect level, might be done to the depth of an inch 

 or more, in the evening, once or twice a week, during very hot weather, 

 without risk of injuring the plants. 



Should, however, the surface of the ericacetum be 5 ft. or 6 ft. below the 

 general surface of the ground, and if it be formed in a soil not naturally very 

 porous and dry, such as gravel or sand, chalk, &c., very little artificial water- 

 ing will be necessary ; and both under drains and surface drains may be 

 omitted. 



In planting an ericacetum, whatever may be the form of the bed, the plants 

 ought to be placed so far apart as to allow them to branch out freely in every 

 direction without touching one another. It is only when they are grown in t 

 manner that they flower freely, and become covered with flowers on 

 side, and over the whole plant. In the after-management, whenever anv 



