2 32 INDEX. 



PAGF 



Figure 26. Method of using tile-hook 108 



27 . Section of stone abutment for drain outlet 117 



28. Box outlet for tile drain 117 



Digging a ditch for twelve-inch tile facing 144 



Laying twelve-inch drain -tile '' 146 



A dredged drainage-ditch ten years after excavation " 152 



29 . Proper curve for open ditches 155 



30. Action of current on ditch-banks at curves 156 



31 . Section of ditches with computations ^ 163 



32. Junction of shallow ditch with deep main 177 



33 . Sections of open ditches 178 



34. Catch-basin for surface drainage. 181 



35 . Catch-basin constructed of sewer-pipe 182 



36. Orchard drainage 185 



37. Location for sm-face ditches and tile drains in road con- 



struction 191 



38. Tile drain to intercept seepage water 192 



39. Combined brick and clay road 197 



Twenty-inch diain-tile distributed for laying through a 



swamp facing 200 



Thirty-inch drain-tile distributed along the line of a sur- 

 veyed drain facing 202 



40. Tile drain with a relief surface ditch 202 



41 . Classification map of a drainage district 206 



