Alkali Water not Suitable for Irrigation 267 



sible to state with certainty precisely how these ele- 

 ments were combined in the sample. It is more 

 unfortunate that chemists are not agreed as to how 

 results should be interpreted, and that different sys- 

 tems are followed by different analysts. But what is 

 most unfortunate of all, is that many chemists have 

 published their computed results, as though there 

 were but one interpretation of them, and have not 

 given the data upon which their computations were 

 based. Hence, we have found it impossible to arrive 

 at what may be regarded as the safe amount of 

 black or white alkali an irrigation water may contain. 

 The table given above represents the opinion of two 

 chemists as shaped by their system of computing the 

 amounts of the alkalies in the samples analyzed, but 

 it must be understood that another chemist using the 

 same data, with a different system of apportionment, 

 would compute either less or more black alkali and 

 more or less white alkali than the authors have 

 credited the samples with as given in the table above. 



We make this explanation, that the irrigator may 

 understand that when the water from a given source 

 is said to contain .022 parts in 1,000 of black alkali, 

 more allowance must be made in regard to accuracy 

 than is required for the statement that the water car- 

 ries in solution 11.234 grains of solids per gallon. 



It should be understood further, as will be shown 

 in the next chapter, that a given quantity of black 

 alkali may prohibit the use of the water for irrigation 

 purposes on one soil, when upon another it may be 

 used with perfect safety. 



