854 



THE IRRIGATION AGE. 



How to 



The continued articles on the ''Primer of 

 Hydraulics," which have been appearing 

 Study the j n y HE IRRIGATION AGE since December, 



"Primer of 1910, form the ground work of a very valu- 



Hydraulics." a ^' e book which will be complete in De- 

 cember of the present year ; it will then be 

 put into book form and placed on the market. 



This work on hydraulics is of especial interest and im- 

 portance to our readers who, as a matter of fact, are all 

 more or less interested in hydraulics, and THE IRRIGATION AGE 

 in thus providing a splendid opportunity for the obtaining of 

 a knowledge of the principles and methods of practical appli- 

 cation of hydraulics, is keeping the interest of its readers 

 in the foreground. There are some good books on this sub- 

 ject in existence now, but they are all of a very technical 

 character, so that the plain business man or irrigation con- 

 tractor is unable to study them understandingly. 



Mr. Smith, the author of the "Primer of Hydraulics," 

 however, has developed the happy faculty of clothing his 

 treatise in such simple language and in describing the prin- 

 ciples so clearly that anyone with a plain, common school 

 education can follow the subject step by step. 



To take up the study of hydraulics successfully the fol- 

 lowing hints are given by the author : There is nothing in 

 the work except what is essential to a full and complete 

 understanding of the subject. Hence the interested student 

 must read, study and digest everything offered. This applies 

 to the mathematical principles particularly, as they form the 

 basis of future application of hydraulic principles to practical 

 problems, and the best way to study them is to take the given 

 problems which are worked in the various issues, and solve 

 them independent of the printed solution, but compare the 

 work with that of the author. Then select similar problems 

 of your own making and apply the given principles for their 

 solution. To fix them in your mind it is necessary to read 

 and reread the articles and to solve problem after problem. 

 In this way proficiency will soon be acquired. 



The Science of Irrigation is as yet hardly 

 Economy in the out of its baby shoes, and it goes without 

 Use of Water saying that the next ten years will witness 

 for Irrigation a tremendous development in this direc- 

 Necessary. tion. As the principles of irrigation are 



better understood and practised, the bene- 

 ' fit of them will become apparent more and more. As a mat- 

 ter of fact irrigation should by no means be confined to 

 arid or semi-arid countries, but can be and should be 

 applied judiciously everywhere, where farmers are raising 

 vegetation. Even countries having an annual rainfall of 

 40 inches or more will experience at times the effect of 

 a drouth which will cause a complete or partial failure 

 of crops; this could be relieved or entirely prevented where 

 a partial system of irrigation is maintained so that in case 

 of a failure of rains to arrive at the right time the farmer 

 can turn his water into his land and supply the deficiency. 

 As the irrigated areas are constantly increasing the mat- 

 ter of economic use of water is receiving attention. This 

 is a very important subject and should be followed up with 

 the most persistent efforts. If conservation of natural re- 

 sources means anything it means that there should be no 

 waste ; it does not mean that our forests or water-falls 

 should be fenced in and kept from being used ; this would 

 be utterly foolish and keep the people from their heritage ; 

 but it means that our national resources should be so 

 handled that they will serve the present generation as well 



as succeeding generations and hence economy in their use 

 is an imperative necessity. 



Economy in the use of water for irrigation purposes is 

 necessary in order to expand the number of acres available 

 for irrigation. It is easily understood that when the pio- 

 neers in irrigation took hold and developed projects it was 

 done on lines of the least resistance and least cost. Thus 

 water was led along rough ditches to the nearest land and 

 the tracts thus irrigated produced splendid results. No one 

 made inquiries as to the quantity of water which actually 

 leaked away from the ditch and was thus wasted. As the 

 value of irrigated land is constantly rising the value of 

 the water thus wasted becomes apparent and means are 

 discussed and adopted to conserve this wasted water; how to 

 accomplish this result to the best advantage is one of the 

 principal problems in irrigation at the present time. 



The following article has been taken from 

 Doubling and the news notes of the Colorado Agricul- 

 Trebling the tural College, Ft. Collins, Colo., written by 



Duty of Water F - B - House: 



T . . How manv farmers are there in the 



in Irrigation. 



country who know what is meant by the 



term "Duty of Water?" Not many. Yet they have been 

 living in an arid section and irrigating their fields for years. 

 They have seen the value of water increase year after year, 

 and they know that water in a reservoir is like money in a 

 bank, and should be used when and where it will do the most 

 good, and made to go as far as possible. 



One farmer uses a certain head of water and with it 

 covers five acres of his farm in a day. Another farmer uses 

 the same head and irrigates only 2J/2 acres with it. The duty 

 of the water in the hands and on the land of farmer No. 1 

 is double the duty in the hands and on the land of farmer 

 No. 2. 



It behooves every farmer, then, to know what duty he 

 is getting out of his water, and, if he finds that he is not 

 up to the standard, he may take the necessary steps to im- 

 prove the position of his ditches or may, during the fall and 

 early winter, cut off the high spots and fill in the low spots 

 of the field and in this way increase the duty of his water 

 two, three, and even fourfold. 



There are two general ways of speaking of the duty of 

 water. One is to state the number of acres a second foot of 

 water will take care of, and the other is to speak of the 

 number of acre feet of water used per acre. 



We used to figure that land in this section needed one 

 second foot of water for every 40 acres, and in this case the 

 duty of water was 40 acres per second foot. Later we raised 

 this duty to 60 acres per second foot; then we made the duty 

 80 acres per second foot, and for a long time it was the 

 custom to provide a second foot of water for each 80-acre 

 tract. Now we are figuring the duty of water to be 100 or 

 120 acres per second foot. 



Can we do better than this? We certainly can, for in 

 southern California, where water is scarce and valuable, they 

 make a second foot of water take care of 300 acres, and 

 where subirrigation, by means of underground pipes, is used, 

 the duty in some cases has reached 1,000 acres per second 

 foot. 



This method, however, of figuring duty is not the best by 

 any means, for it presupposes a continuous flow of 1 second 

 foot throughout the irrigating season. The farmer when he 

 irrigates usually wants more than a second-foot head, and 

 he uses it for a few days or weeks and then uses no water 



