486 IRRIGATION FARMING. 



Catchment— Extent of country that may be utilized in drawing 



water to a certain point, as a reservoir; also catchment 



area. 

 Check — An impediment placed in a lateral to divert water out 



upon the land. 

 Conduit — An aqueduct for passing water; a tube or pipe. 

 Contotnr — The high level line describing the course of a canal. 

 Crown Arch — An arched plate serving as a keystone in a 



masonry curved dam. 

 Cylinder — An enlarged mechanism for a piston at the bottom 



of a pump in a well. 

 Dam — A barrier to confine the flow of a stream to raise its 



level; an embankment of a reservoir. 

 Detritus — Disintegrated material of any kind flowing in a 



ditch; silt or alluvial deposit. 

 Dike — An embankment for holding water. 

 Ditch — An artificial watercourse, one somewhat smaller than 



a canal. 

 Ditching Machine — An implement for excavating canals, etc. 

 Diversion Dam — A structure in a natural stream for diverting 



the water into a canal. 

 Division Box — A contrivance for dividing or apportioning 



water to consumers. 

 Drop Box — An arrangement in a canal for lowering or reducing 



the grade. 

 Duty of Water— Service required of water in supplying land; 



the tax to which water is put in irrigating. 

 Evaporation — The loss of water by vaporizing. 

 Fellah — An Egyptian laborer, cultivator or irrigator. 

 Filament — The center course of a current in a stream. 

 Fill-Bank — Material used in constructing embankments. 

 Filtration — Act of filtering, as water through soil. 

 Flights — A continuous series of lifting buckets or plates in a 



water elevator. 

 Float — An object thrown into a stream to calculate water 



velocity; a water-wheel paddle. 

 Fltnne — A structure or box for conducting water across de- 

 pressions or uneven places. 



