BUREAU OF PUBLIC ROADS. 485 



departments of agronomy and horticulture of the agricultural 

 college. 



In cooperation with the Board of Water Engineers of Texas, a 

 study of seepage losses from irrigation channels of various kinds 

 is in progress in the lower Rio Grande Valley, In this valley 

 the irrigated lands have in some instances two slopes, one away 

 from the river and the other in the direction of its course, the latter 

 being about 1 foot per mile, while the former varies from 6 inches 

 to 4 feet per mile. At the upper end of the valley, near Mission, 

 the ground slopes away from the river at the rate of about 6 inches 

 per mile for a distance of 4 miles to what is known as the second 

 lift. At this point there is an abrupt rise of 32 feet, from which 

 elevation the surface slopes to the north 2 feet per mile for 4 or 5 

 miles to a third lift of about 30 feet. These topographical features 

 make it necessary to operate canals on made embankments at the 

 river end, and the enormous loss by seepage, together with the cost 

 of pumping part of the water through a succession of lifts, render the 

 cost of water to farmers quite high. It is hoped that the investiga- 

 tions now in progress will result in the application of remedial 

 measures which will lessen the present burdensome cost of water. 



In cooperation with the department of public works and the 

 University of California, three major projects were carried on. 

 These were: (1) A study of seepage losses in irrigation channels 

 and economic means for their prevention; (2) a study of the use 

 of irrigation water and its movement in the soil in relation to the 

 duty of water, to its utilization by plants, and to alkali injury; (3) 

 a study of the cost of water to irrigators. None of these projects 

 was brought to completion during the year, but it is expected that 

 investigations of the seepage losses in irrigation channels and of 

 the cost of water to irrigators will be completed during the coming 

 year and reports thereon issued. 



FARM ENGINEERING INVESTIGATIONS. 



The ventilation of farm dairy barns is an engineering problem 

 the importance of which is not generally realized by those engaged 

 in the production of milk. The best methods of maintaining proper 

 atmospheric conditions within the barn have not j^^et been found, 

 because the basic principles involved have not been determined. 

 It has been found that, just as fresh air is necessary to the health 

 and efficiency of human workers confined in close quarters, so it 

 is essential, particularly in cold climates, to the health of farm 

 stock if the milk and meat supply of the country is to be clean 

 and wholesome. It is known that animals do better if the stable 

 is kept dry and at a comfortable temperature. The maintenance 

 of such stable conditions is dependent upon a number of factors 

 the relation of which to one another and their respective effects 

 upon the ventilation of the stable have not been clearly determined. 

 Investigations previously made were 'for the purpose of obtaining 

 general data and determining the constancy of certain factors. Dur- 

 ing the past year these investigations were supplemented by a 

 number of tests designed to corroborate or disprove some of the 

 earlier findings. A large amount of data secured in these tests is 

 being analyzed and it is expected that facts of great value to agri- 

 cultural engineers and designers of ventilating systems will be de- 



