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. CHAPTER VIII. ARRANGEMENT OF DRAINS. Necessity of System.--What Fall is Necessary.--American Examples.--Outlets.--Wells and Relief-Pipes.--Peep-holes.--How to secure Outlets.--Gate to Exclude Back-Water.--Gratings and Screens to keep out Frogs, Snakes, Moles, &c.--Mains, Submains, and Minors, how placed.--Capacity of Pipes.--Mains of Two Tiles.--Junction of Drains.--Effect of Curves and Angles on Currents.--Branch Pipes.--Draining into Wells or Swallow Holes.--Letter from Mr. Denton. CHAPTER IX. THE COST OF TILES--TILE MACHINES. Prices far too high; Albany prices.--Length of Tiles.--Cost in Suffolk Co., England.--Waller's Machine.--Williams' Machine.--Cost of Tiles compared with Bricks.--Mr. Denton's Estimate of Cost.--Other Estimates.--Two-inch Tiles can be Made as Cheaply as Bricks.--Process of Rolling Tiles.--Tile Machines.--Descriptions of Daines'.--Pratt & Bro.'s. CHAPTER X. THE COST OF DRAINAGE. Draining no more expensive than Fencing.--Engineering.--Guessing not accurate enough.--Slight Fall sufficient.--Instances.--Two Inches to One-Thousand Feet.--Cost of Excavation and Filling.--Narrow Tools required.--Tables of Cubic contents of Drains.--Cost of Drains on our own Farm.--Cost of Tiles.--Weight and Freight of Tiles.--Cost of Outlets.--Cost of Collars.--Smaller Tiles used with Collars.--Number of Tiles to the Acre, with Tables.--Length of Tiles varies.--Number of Rods to the Acre at different Distances.--Final Estimate of Cost.--Comparative Cost of Tile-Drains and Stone-Drains. CHAPTER XI. DRAINING IMPLEMENTS. Unreasonable Expectations about Draining Tools.--Levelling Instruments.--Guessing not Accurate.--Level by a Square.--Spirit Level.--Span, or A Level.--Grading by Lines.--Boning-rod.--Challoner's Drain Level.--Spades and Shovels.--Long-handled Shovel.--Irish Spade, description and cut.--Bottoming Tools.--Narrow Spades.--English Bottoming Tools.--Pipe-layer.--Pipe-laying Illustrated.--Pick-axes.--Drain Gauge.--Drain Plows, and Ditch-Diggers.--Fowler's Drain Plow.--Pratt's Ditch-Digger.--McEwan's Drain Plow.--Routt's Drain Plow. CHAPTER XII. PRACTICAL DIRECTIONS FOR OPENING DRAINS AND LAYING TILES. Begin at the Outlet.--Use of Plows.--Leveling the Bottom.--Where to begin to lay Pipes.--Mode of Procedure.--Covering Pipes.--Securing Joints.--Filling.--Securing Outlets.--Plans. CHAPTER XIII. EFFECTS OF DRAINAGE UPON THE CONDITION OF THE SOIL.