.1/2 T. FURUTA. 



small dose ; others have observed a considerable diminution of 

 the yield on the application of 4000-5000 kilo, of carbonate of 

 lime per hectare, especially with legumes. 



Various methods have been employed in estimating the 

 amount of lime necessary for the liming of the soil, but in many 

 instances no attempt at all has been made to reach an approxi- 

 mate calculation, the amount of lime applied to a given extent 

 of the field surface having been in fact arbitrary. Of course a 

 reliable test in regard to the required dose of lime can be made 

 from crops growing on the soil, limed in various degrees, but this 

 empirical method would be very inconvenient and time consum- 

 ing. In cases where merely the acidity of the soil has to be 

 corrected with lime, the determination of the amount of lime to 

 be applied would be simple. But such cases are exceptional 

 and relate merely to soil improvement. 



Recently an article was published by D. Meyer 1 on the lime 

 compounds of the soil and the determination of the assimilable 

 amount of lime. He found among other things that with the so- 

 called light soils the solubility of the lime and magnesia in dilute 

 acid was less than with heavy soils, and that the finest particles 

 of the soil contained relatively more lime than the coarser 

 particles. He further observed that the most favorable lime 

 compound was the carbonate and the slaked lime, which latter 

 yields carbonate in a finely divided condition. 2 It had a favor- 

 able action even in cases in which gypsum had proved unfavor- 

 able. He asserts that the assimilable lime can be extracted by 

 digestion of the soil with \0% solution of ammonium chlorid for 

 three hours at ioo°C. 3 Thus the lime can be directly determined 

 in the filtrate without the previous separation of the silica. The 

 principal value of this method is according to the author that 

 the lime content thus determined shows a much better corre- 

 spondence with the yields of the harvest, relative to the quanti- 

 ties of lime which the crop could extract from the soil. He 

 further concluded that a lime content of 0.25% in the soil can 



1 Landwirthschaftliche Jahrbiicher Vol 29, p. 914 (1900). 



2 Others, however, have observed that in certain cases gypsum is the most favorable 

 form. 



3 E. Hotter proposes to determine the amount of assimilable lime by extraction with 

 acetic acid of 2.0%. Z. landw. Vers. Oesterreich 1901. 



