CONTENTS. VU 



CHAPTER X. 



SIZE OF LATERAL DRAINS. 



PAGE 



Provisions for Unusual Rainfall — Selection of Tile — Tabulating Tile 



for Drains , 144 



CHAPTER XI. 



OPEN DRAINS. 



Grade for Open Ditches — Mean Velocity of Flow — Relation of 

 Breadth and Depth of Channel to Surface and Mean Velocity 

 -Curvature of Ditches-Form and Depth of Ditches— Capacity 

 Required for Open Ditches — Quantity of Water per Acre to be 

 Removed — Formula for Flow in Open Ditches — Waste Banks 

 and Berm — Surveys for Open Ditches —Computing Excavation 

 — Ditching with Steam-dredges — Ditching with Teams — Dis- 

 charge of Side Ditches into Main — Special Form for Ditches. . , 150 



CHAPTER Xn. 



DRAINAGE OF BARNYARDS, CATTLE-LANES, ETC. 



1 



Drainage of Barnyards — Taking Surface-water into Underdrains — 

 Drainage of Cellars and Residence Grounds — Drainage of 

 Fruit Orchards 179 



CHAPTER XIIL 



ROAD DRAINAGE. 



Earth Roads — Gravel and Earth Roads — Seepage-water on Roads 

 — Surface Drainage of Hill Roads — Culverts and Cross-drains 

 — Drainage of Paved Roads — Combined Brick and Clay Road . 187 



CHAPTER XIV. 



DRAINAGE DISTRICTS. 



Working Plans — Theory of the Classification of Lands — Classifi- 

 cation for Assessment Purposes — Classification Map — Com- 

 puting Assessment Roll — ^Mutual Cooperative Drainage 199 



