211 



acid, originally suggested by Wagner as a standard solvent for 

 estimating the probable availability of phosphate of lime in basic 

 slag. Such a solution, however, is far stronger than the sap acidity 

 of plants, and in order that an acidity or solvent action less than 

 that possessed by the sap of farm crops should be represented, 

 Mr. Hughes tried a o.i per cent solution of citric acid. With such 

 a solution he found that i part of caustic lime was dissolved in 

 809 parts of the solution while i part of chalk was dissolved in 

 984 parts. Comparing the actual lime in quicklime with that in 

 chalk, it appears that in pure cold water caustic lime is about 27 

 times more soluble than chalk, but that in the o.i per cent, so- 

 lution of citric acid lime is only about twice as soluble as the lime 

 in the form of chalk. 



It seems clear, therefore, that if chalk be reduced by grinding 

 to as a fine a condition as caustic lime, it will be sufficient to 

 apply i ton per acre of ground chalk instead of 10 cwt per acre 

 of ground lime. The ground chalk would usually be both less costly 

 than ground lime, and more convenient to apply. At the same 

 time it would have a less rapid action in the destruction of ve- 

 getable matter in the soil. Mr. Hughes remarks that the value 

 of chalk for all light soils has been too much neglected. The red 

 soils of Worcester and Hereford are, he says, types of soils that 

 would be improved by dressings of finely-ground chalk, which is 

 also suitable for gravel, granite, and sandy soils deficient in ve- 

 getable matter as well as in lime. The chalk should be dried and 

 ground finely, distributed evenly, and lightly harrowed in. 



J. AUGUSTUS VOELCKER. Experiments at Woburn, on the use. 



of Lime. Journal of the R. Agric. Soc. of England, Vol. 70, 

 1909, pp. 361-388. 



The experiments were begun in 1908, in order to test the value 

 of lime in a rotation. 



Lime was applied in the one case as lump lime, at the rate of 

 2 tons per acre (5025 kg. per hectare) in the other as ground lime 

 in smaller quantity, viz. 10 cwt per acre (i 257 kg. per hectare). 

 The crop of 1908 was barley, and the land which is poor in lime 

 showed the advantage of using lime, the crop being increased by 

 17 bushels per acre (15.27 hectolitres per hectare) in the first year 

 through the heavier application of lime. Red clover was the crop 

 for 1909 but owing to damage caused by frost, by wood pigeons 



