IRRIGATION AND DRAINAGE INVESTIGATIONS. 29 



courts, and irrigation officials generally, a standard for determining 

 the size of canals to serve given areas, and the quantities of water 

 which should be allotted to parties who had acquired rights to water. 

 This work was continued for four years. The close agreement in the 

 averages of our measurements for the four years showed that they 

 correctly represented general practice and furnished a safe basis 

 for engineers and officials. There is still a demand for such data for 

 sections not included in our previous measurements, and this work is 

 being continued. In 1905 measurements of the quantities of water 

 used in general practice were made in Washington by Professor 

 Waller, of the Washington Agricultural Experiment Station, and in 

 Oregon by Mr. Stover, of this Office. 



The facts brought out most prominently by our measurements are 

 the great difTerence between the quantities of water diverted and the 

 quantities received by the land, representing a large loss in convey- 

 ance; and the great difference in the quantities received by different 

 tracts of land under apparently similar conditions, representing 

 wasteful use on the part of those using the larger quantities. The 

 work on the duty of water has therefore been developed along new 

 lines — studies of the water requirements of crops, the most econom- 

 ical methods of supplying them with the necessary water; and 

 methods of preventing losses from canals by seepage and from land 

 surfaces by evaporation. 



The studies of water requirements of crops are of two classes: (1) 

 Tank experiments to determine the quantities of water consumed by 

 plants in the process of growth. These were carried on in lOO-l and 

 1905 in California by Professor Fortier; (2) plat and field experi- 

 ments to determine the quantities of water which produce the largest 

 returns. Work on this line was carried on in California. Utah, 

 Nevada, Colorado, and New Mexico in 1005. In Utah this work 

 included plat experiments at the State experiment station, where 

 plats were irrigated according to regular programmes, giving them 

 different quantities of water, and applying it at different intervals 

 of time and different stages in the life of plants. In addition, agi'ee- 

 ments were made with farmers in different parts of the State, imder 

 which they irrigated a part of their land according to their own 

 judgment, parts of the remainder receiving different proportions of 

 the quantity received by the field irrigated according to the farmers' 

 judgment. Records of the crops raised will show what quantity of 

 walci- has jjroduced the best results. These experiments should be 

 continued several years l)efore definite conclusions can l)e drawn. 

 The work at the station was under the direction of Prof. W. W. Mc- 

 Laughlin, and that in other parts of the State under Mr. E. R. Mor- 

 gan, of this Office. The work in Nevada was similar to that done at 



