IN, EVAPORATION AND FILTRATION.

Fertilizing Substances in Rain Water.--Amount of Rain Fall in
United States; in England.--Tables of Rain Fall.--Number of Rainy
Days, and Quantity of Rain each Month.--Snow, how Computed as
Water.--Proportion of Rain Evaporated.--What Quantity of Water Dry
Soil will Hold.--Dew Point.--How Evaporation Cools
Bodies.--Artificial Heat Underground.--Tables of Filtration and
Evaporation.

CHAPTER IV.

DRAINAGE OF HIGH LANDS--WHAT LANDS REQUIRE DRAINAGE.

What is High Land?--Accidents to Crops from Water.--Do Lands need
Drainage in America?--Springs.--Theory of Moisture, with
Illustrations.--Water of Pressure.--Legal Rights as to Draining our
Neighbor's Wells and Land.--What Lands require Drainage?--Horace
Greeley's Opinion.--Drainage more Necessary in America than in
England; Indications of too much Moisture.--Will Drainage Pay?

CHAPTER V.

VARIOUS METHODS OF DRAINAGE.

Open Ditches.--Slope of Banks.--Brush Drains.--Ridge and
Furrow.--Plug-Draining.--Mole-Draining.--Mole-Plow.--Wedge and
Shoulder Drains.--Larch Tubes.--Drains of Fence Rails, and
Poles.--Peat Tiles.--Stone Drains Injured by Moles.--Downing's
Giraffes.--Illustrations of Various Kinds of Stone Drains.

CHAPTER VI.

DRAINAGE WITH TILES.

What are Drain-Tiles?--Forms of Tiles.--Pipes.--Horse-shoe
Tiles.--Sole-Tiles.--Form of Water-Passage.--Collars and their
Use.--Size of Pipes.--Velocity.--Friction.--Discharge of Water
through Pipes.--Tables of Capacity.--How Water enters Tiles.--Deep
Drains run soonest and longest.--Pressure of Water on
Pipes.--Durability of Tile Drains.--Drain-Bricks 100 years old.

CHAPTER VII.

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 Aqueduct