THE LIME-MAGNESIA RATIO 103 



high. No connection could be traced between the Hme-magnesia 

 ratio and the productiveness of the soil. Indeed table 58 shows 

 that very good and very poor soils may have practically identi- 

 cal ratios." The table referred to gives analyses of the soils of 

 England in question which make clear the relationships between 

 lime and magnesia in them. 



In further experimental work Haselhoff"*^ has shown by a se- 

 ries of pot experiments with different crops that it was impossible 

 to substantiate Loew's theory on the necessity for a definite 

 ratio of lime to magnesia for every kind of crop. The results 

 obtained in the growth of these plants were such as to give no 

 opportunity for correlating the want or the presence of good 

 plant development with the total quantities and ratios of lime 

 and magnesia in soils tested in the pots. 



Similarly Hopkins^" describes a series of experiments in pots 

 ^vith wheat on the Marshall brown silt loam, one of the typical 

 soils of Illinois. These experiments showed that magnesium car- 

 bonate was harmless to the wheat w^hen added to the soil con- 

 stantly up to 0.8%. In amounts exceeding that it suddenly 

 became very toxic. In attempting to neutralize such toxic ef- 

 fects, additions of calcium sulphate were made in varying quanti- 

 ties to the harmful quantity of magnesium carbonate, but in the 

 words of Hopkins "httle support" was found for ''Loew's ratio 

 from these data." 



In making a study of Indian soils with particular relation to 

 acid conditions in them, Meggitt" carried out a series of experi- 

 ments which resulted among other things, in the following state- 

 ment by him: "The results of our experiments do not at all con- 

 nect the value of lime with any such relationship," referring to 

 Loew's lime-magnesia ratio. The work was carried out on an 

 acid soil and plots in the field were used. 



Of less emphasis, but of similar significance is the investiga- 



*•> Landw. Jahrb., vol. 45, 1913, no. 4, p. 609. Cited fromE. S. R., vol. 31, no. 1, 

 p. 31, 1914. 



5" Soil Fertility and Permanent Agriculture, p. 170-172, Ginn and Company, 

 1910. 



" Mem. Dept. Agr. India, vol. 3, no. 9, p. 240. 



