26 LANDSCAPE GARDEN SERIES 



The size of tile and catchbasins is governed by local conditions 

 as to rainfall, grade, etc. Four-inch tile is used on most drives of 

 moderate length and width, but six-inch tile is often required. Ordi- 

 nary porous farm tile is sufficient where there is plenty of "fall", and 

 no trees nearby whose roots will choke up the tile, and if the tile-line 

 is thirty inches or more deep. Otherwise, vitrified tile with cemented 

 joints is necessary. 



Brick, stone, cement and gravel are the materials commonly used 

 for drives. Brick is used less than other materials named. Stone and 

 gravel construction of various types seem to be most popular, especially 

 on large suburban or country places. Cement drives are numerous 

 on small city places, and are to be found on many country places 

 where the owner has decided in favor of permanence and minimum 

 upkeep. The first cost of cement construction is greater than that of 

 stone, macadam or gravel, although bituminous macadam is not much 

 cheaper. 



The thickness of the drive depends on the weight of traffic it has 

 to bear. Six inches is the minimum for permanence, even on the small 

 city place. 



Having prepared profile and drainage, the next step is to prepare 

 the subgrade by excavating or filling to attain the desired grade. The 

 subgrade should be shaped to the same cross-section as the finished 

 surface of the drive, and all soft spots or irregularities should be rem- 

 edied so that when a heavy roller is run over the subgrade it remains 

 smooth, firrm, and of proper grade and crown throughout. This 

 preparation of subgrade applies to all forms of construction in drives. 



The foundation course is laid when the subgrade is completed. 

 For stone or gravel roads this course should be spread evenly to 

 proper grade and shape and thoroughly rolled. This done, the wear- 

 ing course is added and the whole drive is given, a final thorough 

 rolling. 



The surface of a stone road may be of white, yellowish, or gray 

 screenings rolled on while wet, or it may have a dark surfacing of 

 asphalt, Tarvia or similar bitumen. On either "water-bound" or 

 bituminous macadam a thin coat of pea gravel or colored granite 

 screenings adds to the surface appearance. Gravel drives with clay 



