40 
Dimensions for automatic siphons. 
Dimension. 
Diameter of siphon 
Diameter of bell 
Diameter of discharge head. 
Drawing depth 
Depth of trap 
Width of trap 
Height above floor 
Clearance under bell 
Diameter of carrier 
Invert to discharge line 
Average discharge per second. 
.cubic feet. 
Reference 
letter. 
Inches. Inches, j Inches. 
3 
10 
4 
13 
12 
10 
'4, 
2 
4 
20| 
0.16 
4 
12 
4 
14 
13 
12 
8| 
2 
4-6 
224 
0.35 
15 
6 
23 
22 
14 
9| 
3 
6-S 
33J 
0. 73 
G*T£ GHMflfBER -9 
X 
i 
-SO' ■ 
Fig. 32. — Ground plans of tile sewage disposal systems. 
THE FINAL DISPOSAL SYSTEM. 
DISPOSAL BY SURFACE OR SUBSURFACE DISTRIBUTION. 
Where the soil is porous or sandy and there is plenty of area 
available which is used for no other purpose, the sewage from the 
septic tank may be discharged through 4-inch distribution tile laid 
on the surface of the ground in gridiron or herringbone fashion. 
Four hundred and fifty to 500 square feet of area are necessary for 
each person served if the soil is very porous and sandy, and the soil 
should either be tile-drained or have natural underdrainage. 
