1918] Lipman-GericJce : CaCO s and CaS0 4 and Soil Solution 27/ 



that point. The calcium and sulphur content of the soil solution behave 

 as one would expect without experiment in the clay adobe soil treated 

 with CaS0 4 . but the calcium content of the same soil treated with 

 CaC0 3 is affected to a small degree in some cases and not at all in 

 others. The magnesium content of the clay adobe soil solution behaves 

 similarly to that of the Oakley soil solution, but the increases due to 

 CaC0 3 treatment of the soil are not as large in the former as in the 

 latter. Again CaS0 4 seems to be without effect in that direction. In 

 general, the behavior of the clay adobe soil solution, as judged by our 

 analyses, parallels that of the Oakley soil solution in the third samp- 

 ling, a condition of equilibrium, and, in general of a more dilute 

 solution, having been attained. That does not hold, however, for the 

 soil treated with CaS0 4 . In general, therefore, the results obtained by 

 us with the clay adobe soil, among other things, show a lack of agree- 

 ment between our results and those of Briggs and Breazeale regarding 

 the effect of CaC0 3 and CaS0 4 on the potassium content of the soil 

 solutions in question. 



Coming finally to a consideration of the greenhouse soil, we find in 

 table 3 some very interesting data, and the most definite of any sub- 

 mitted in all the tables, inasmuch as the changes due to soil treatment 

 are so much larger than those characterizing the other soils. Con- 

 sidering the data for potassium first, we find that marked increases in 

 the amount of that ion in the solution of the greenhouse soil are 

 induced by the larger application of CaC0 3 and by both the smaller 

 and larger applications of CaS0 4 . Moreover, even the smaller appli- 

 cation of CaC0 3 seems to induce the solution of definitely larger 

 amounts of potassium than those found in the solution of the untreated 

 greenhouse soil. In the periods of the first two samplings, the iron 

 content of the soil extract seems to have been increased by the CaCO., 

 applications, but not by the CaS0 4 applications. Moreover, the smaller 

 CaCO. application seems to have been much more effective in that 

 direction than the larger application. By the time of the third 

 sampling, the effects just mentioned appear to have vanished, and in 

 fact, it is possible that they have been supplanted by a depression in 

 the amount of iron in the soil extract. The general direction taken 

 by the effects of the soil treatment on the calcium content of the soil 

 extract is what one would expect a priori. The results indicate, how- 

 ever, the inaccuracy of the method of determination considered, in the 

 large, since the relations between the CaCO., and CaS0 4 applications 

 in small and large amounts do not maintain themselves constant. 



