442 Transactions of the 



applied in an ordinary season to make one crop, will be proved by ex- 

 perience. It is said by farmers on the adobe lands on the west side of 

 the San Joaquin that four inches of rain, coming in the latter part of the 

 season, is sufficient to make a crop. There is no obvious reason why an 

 equal quantity of water applied by irrigation should not accomplish an 

 equal result. In some of the successful experiences that were had last 

 year, a larger quantit}' was consumed; but the fact is well attested that 

 in these operations far more water was wasted than was utilized, through 

 inexpertness in applying it. 



The intelligent reader perceives that the method of applying the 

 water to the land by this system of furrows following the line of steepest 

 inclination, with "checks" connecting those furrows at right angles to 

 their direction, is as applicable in all its detail to the " uneven " lands 

 east of the San Joaquin as to the absolute inclined plane of the west side. 

 The only difference in method is that diversity of directions to be taken 

 by the furrows which was indicated in the preceding description of the 

 "uneven" lands. The distances to be left between the "checks" and 

 dams, to give equal depths of water at each irrigation, depends on the 

 inclination of the surface diminishing as the degree of slope increases. 

 If a greater depth of water be given at one time, the distance between 

 the "checks" ma}* be increased, but the distribution cannot be made 

 equally uniform. Those portions of the field next above the "checks" 

 and on which the water stands deepest, will absorb a greater amount 

 than the more distant portions, on which it is shallower. Bj* increasing 

 this depth much above four inches, it would not be difficult to drown 

 out a portion of the crop while another portion should fail to receive 

 sufficient for its needs. Some irregularity of distribution is inevitable, 

 but the nearer together the "checks" are put, and the less the depth 

 of water given at any one time, the more uniform will be the effect. It is 

 plain that the results of farming with irrigation, as of that without irri- 

 gation, will differ under the hands of different men; and that, in the one 

 case as in the other, the more intelligent operator, and who is willing to 

 give more downright honest work to his operations, will achieve the best 

 results. 



On the inclined plane lands of the west side the detail of applying the 

 water may be varied. The farm ditch may be run on an east course, on 

 which the land falls at the rate of eight feet to the mile. It will also 

 fall away from the north side of this ditch at the rate of one foot to the 

 mile. Main irrigating furrows run from this ditch both northeast and 

 southeast will have a rate of inclination intermediate between these 

 two — slightly greater for the northerly set, but the difference would be 

 inappreciable in practice. These furrows could be run so that each 

 northeast furrow from one ditch would meet the corresponding south- 

 east furrow from the ditch next north of it. Thus an irrigating system 

 would be laid out upon the whole surface of the ground resembling the 

 skeletons of fishes, whereof the several farm ditches would be the back- 

 bones, each with its system of ribs attached, formed by the main irri- 

 gating furrows. This is, in fact, the plan that was adopted last season 

 by the canal company in laying the water on the five thousand-acre field 

 which they have rented as a sort of model farm from Lux & Miller. The 

 water is applied through this system by the same method already indi- 

 cated — alternately throwing up and hoeing out a succession of dams 

 across the irrigating furrows, backing up the water in them till it over- 

 flows the adjacent soil. The proper series of " checks " produces the 

 necessary uniformity of distribution to each part. 



