WALKS AND DRIVES 



25 



Fig. 10 The fountain is unsurpassed as a featute in such locations 



lect at the lowest points, and unless the grade is very slight, surface 

 water will also wash out the drive. To facilitate surface drainage 

 the drive should be "crowned" at least two inches in the center. The 

 steeper the grade the higher the crown required. 



Catchbasins are installed at regular intervals, at turns, and wherever 

 the tile line changes grade. If the slope of the drive is very gentle, catch- 

 basins may be as much as 150 feet apart. On steep grades the catch- 

 basins should not be over 50 feet apart on a stone drive. During rain- 

 falls, thaws, etc., water rapidly accumulates and drains off along the 

 sides of the drive ; and the catchbasins should be) so placed that water 

 accumulating in the intervals between them cannot acquire enough 

 volume or velocity to wash out the drive, nor fill low places faster than 

 the catchbasins at those points can carry off the water. 



