PAGE. Elkington's Mode 32, 33 Ditch and Bore-hole 35 Keythorpe System 42 Theory of Springs 80-84 Plug Drainage 106, 107 Mole Plow 108 Wedge Drains 111 Shoulder Drains 111 Larch Tube 112 Pole Drain 113 Peat Tiles and Tool 113 Stone Drains 115-117 Draining Bricks 121 Round Pipes 122 Horse-shoe Tile 124 Sole-Tile 125 Pipes and Collar 126 Flat-bottomed Pipe-Tile 129 Drains across Slope 150 Draining Irregular Strata 162 Relief Drains 162 Small Outlet 178 Large Outlet 179, 180 Outlet, with Flap 181 Well, with Silt Basin 186 Peep-hole 188 Spring in Drained Field 189 Main of Two Tiles 194 Main of Several Tiles 194 Plan of Drained Field 195 Junction of Drains 196 Branch Pipe 197 Daines' Tile Machine 209 Pratt's Tile Machine 210 Tiles, laid well and ill 229 Square and Plumb-Level 229 Spirit Level 230 Staff and Target 231 Span, or A Level 232