ILLUSTRATIONS.

Fig. 1. Shallow barnyard well 6

2. Portable earth closet 8

3. Old form of earth closet 9

4. Earth closet and dry catch 10

5. Self-acting peat dust closet 11

6. Settling chamber and flush tank for

irrigation 12

7. Subsurface irrigation of sewage 13

8. Garbage cremator 16

Sewage Disposal on the Farm, and Protection of Drinking Water · 第 10 / 24 题