72 MANUAL OF GARDENING 
adjacent lots, so there is a practical advantage in having the level 
of the street lower than that of the ground adjoining. The 
appearance of houses and home grounds is also much better 
when they are higher than the street, and for this reason it is 
usually desirable to keep the latter as low as possible and give 
the underground pipes sufficient covering to protect them from 
frost. Where the ground is high and the sewers very deep, 
the grades should, of course, be determined with reference to 
surface conditions only. It sometimes happens that this gen- 
eral arrangement of the grades of home grounds, which is 
desirable on most accounts, causes water from melting snow 
to flow over the sidewalk in the winter time, where it may 
freeze and be dangerous to pedestrians. A slight depression of 
the lot away from the sidewalk and then an ascent toward the 
house would usually remedy this difficulty, and also make the 
house appear higher. Sometimes, however, a pipe should be 
placed underneath the sidewalk to allow water to reach the street 
from inside of the lot line. The aim in surface drainage should 
always be to keep the traveled portions of the street in the most 
perfect condition for use. The quick removal of surplus water 
from sidewalks, crossings, and roadways will help insure this 
result.” 
These remarks concerning the curbings and hard edges of 
city streets may also be applied to walks and drives in small 
grounds. Figure 69, for example, shows the common method of 
treating the edge of a walk, by making a sharp and sheer ele- 
vation. This edge needs constant trimming, else it becomes 
unshapely; and this trimming tends to widen the walk. For 
general purposes, a border, like that shown in Fig. 70, is better. 
The sod rolls over until it meets the walk, and the lawn-mower 
is able to keep itin condition. If it becomes more or less rough 
and irregular, it is pounded down. 
If it is thought necessary to trim the edges of walks and drives, 
then one of the various kinds of sod-cutters that are sold by 
