116 CHEMICAL EQUILIBRIUM AND ANTAGONISM 



posed of 4590 parts per million sodium chloride, 980 parts 

 per million sodium sulphate, and 830 parts per million of 

 sodium carbonate, found that applying sulphuric acid at 

 the rate of about 119 parts per million was especially bene- 

 ficial, and up to about 451 parts per million, the highest 

 quantity added, the treatment was beneficial. Gypsum 

 also caused a higher yield of barley. The treatments were 

 thought to be helpful both by neutralizing the sodium car- 

 bonate and also by causing a beneficial shrinkage of colloids. 



A number of investigators have noted an antagonistic 

 effect of the heavier metals, such as calcium, copper, and 

 zinc, on the common alkali salts. Caldwell (i) thinks 

 from his observations that this antagonistic effect is due 

 to a dilution of the active salts and not to an actual an- 

 tagonism. He did not find an antagonistic action between 

 sodium and potassium, but on the contrary he found a 

 decrease in the stimulating effect when certain concentra- 

 tions of potassium salts were diluted with sodium salts. 

 Ammonia and sodium in the proportion of i to i gave the 

 best growth in highly concentrated solutions. 



The author (3) found the antagonistic effect in solution 

 cultures to be greater than when the same mixtures were 

 present in soils. 



Some of the most positive antagonistic results in soils 

 appear in the work of Lipman and his associates on soil 

 bacteria. On the ammonification organisms he (9) found, 

 no antagonism between mangesium and calcium nor be- 

 tween sodium and calcium, but there was an antagonistic 

 effect both for these and the nitrifying organisms when any 

 two of the three alkali salts sodium chloride, sodium 

 carbonate, and sodium sulphate were in the soil together. 

 There was antagonism between toxic as well as between 

 stimulating concentrations of these salts. The nitrogen- 



