CHAPTER VII.. Direction, Distance and Depth of Drains.

DIRECTION, DISTANCE AND DEPTH OF DRAINS.

DIRECTION OF DRAINS.--Whence comes the Water?--Inclination of Strata.--Drains across the Slope let Water out as well as Receive it.--Defence against Water from Higher Land.--Open Ditches.--Headers.--Silt-basins.

DISTANCE OF DRAINS.--Depends on Soil, Depth, Climate, Prices, System.--Conclusions as to Distance.

DEPTH OF DRAINS.--Greatly Increases Cost.--Shallow Drains first tried in England.--10,000 Miles of Shallow Drains laid in Scotland by way of Education.--Drains must be below Subsoil plow, and Frost.--Effect of Frost on Tiles and Aqueducts.