124 GARDEN PLANNING 



be filled in or drained; otherwise they will 

 become pools in wet weather. As with lines, 

 so with surfaces : the curves should flow without 

 break, so that we cannot detect where one 

 runs into the other. 



Grass slopes should be used sparingly, be- 

 cause they involve extra labour in the mowing 

 and are apt to suffer in time of drought. When 

 necessitated by the nature of the ground, as 

 in a hillside garden, they should not be steeper 

 than one in two, or both these disadvantages 

 will be intensified. 



Another point to be considered in the making 

 of a grass plot is its level relative to the adja- 

 cent paths. It is not unusual to find paths 

 sunk so much below the grass level that the 

 soil is exposed beneath the turf. This allows 

 soil to break away, or be washed out by the 

 rain, to the detriment of the path. It also 

 involves additional labour in trimming the 

 grass edges. There is no need to allow more 

 elevation to the turf than is sufficient to ensure 

 the mower clearing the gravel when used on 

 the edge of the grass, and if this rule is followed 

 there is no danger of gravel straying on to the 

 grass. From two to three inches is quite 



