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Cost of canals. — The cost of constructing permanent canals is con- 

 siderable. Between the river or lake b:iok, at the initial point, and the 

 general levei of the table lands, and in crossing occasional depressions 

 ilia levees must be both high and wide at the base. The canal must 

 run upon a divide in order that it may not cross any streams and may 

 be sufficiently above the general level to water all portions of the adja- 

 cent count) y. The lands where the levee is to be constructed sliould be 

 thoroughly ploughed before excavation is commenced ; otherwise thc» 

 fresh dirt placed upon the sod does not sufficiently cement to prevent 

 seepage. 



Outlets. — The outlets for flooding the fields must be carefully pro- 

 tected or the crawfish will dig under the gates from the inside and eaus© 

 a crevasse. A very successful plan is to bed a sill 4 by 6 inches in siz© 

 across the bottom of the opening near the inner end and level with the 

 bottom, allowing the ends of the sill to project into the bank on either 

 side of the opening 6 feet ; then plank along the inner side of the silS 

 the full length, using boards 3 feet long, with the top of the boards 

 resting against and even with the sill. The boatds should stand at at 

 angle of 45 ® , the lower ends being near the center of the canal. At 

 each end of this planking a board of the same length and about 1% 

 inches wide should be nailed at a right angle with the planking, thus 

 projecting downward into the earth. Posts should be set against the 

 sill at each side of the cut and at the ends, and the boarding from the 

 sill to the top of the tank should be solid except at the outlet. A 12- 

 inch board should be nailed at a right angle with the face of the crib- 

 bing back into the bank at the end of the sills to stop crawfish. T\m 

 opening should be boarded on the sides and bottom, and this should 

 extend 6 feet outside the cut to prevent underming from the overflow. 

 The gate may be raised by a lever or otherwise. Openings thus con- 

 structed are paoof against damage by crawfish. 



When a large number of planters are drawing their supply of water 

 from the same canal seme will use more than is necessary and increase 

 the expense of the general supply. Some plant very early and require 

 water a month before the general crop is ready. These and other inci- 

 dents can generally be settled with little friction. 



Deep wells for irrigation. — Scarcely had the surface canals been ac- 

 cepted as a success when southwestern Louisiana was startled by the 

 announcement that there were strata of gravel at 125 to 200 feet under 

 the surface of the entire section containing an unlimited supply of water 

 which would, of its own pressure, come so near the surface that it could 

 be readily pumped. This was received with considerable incredulity at 

 first, but repeated tests have firoved that there is a bed of gravel nearly 

 50 feet in thickness underlying this section of Louisiana which Carrie? 

 a large amount of soft water with sufficient presiure to bring it nearly 

 to the surface. Pipes of 2,8, 4, 6, and 8-inch size have been sunk to 

 the gravel and pumped continuously for months without diminution of 

 the supply. The water is soft, at a constant temperature of about 70 

 degrees, and absolutely from injurious seeds or minerals. Such is the 

 facility with which these wpIIs are made that a 6-inch tube has beeiL 

 put down to the full depth required — 200 feet — in fourteen hours. Thus 

 far it has been found that a 2-in3h pipe will furnish sufficient water tc 



