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of soils, the excess or deficiency of which chiefly determines 

 the fertility or barrenness of soils. Schubler's classification, 

 however, has the merit of being easily applicable in practice 

 to ordinary farming, as it does not depend on elaborate che- 

 mical analysis but only on such rough and ready methods of 

 analysis as an intelligent and educated farmer can easily 

 command. 



6 r. To determine the class of any soil according to 

 Schubler's Table, the following direction should be followed : 



(1) Take 100 grains of a well pulverized soil after drying 

 it for | an hour in an air or oil both at 25oF. Heat it in a 

 platinum crucible for half an hour, stirring the mass occa- 

 sionally. Cool in a dessicator and weigh. The loss of 

 weight is calculated as Humus. 



(2) Digest the residue in the platinum crucible in a phial 

 with cold diluted Hydrochloric acid in the proportion of .\ ounce 

 of acid to 10 ounces of water to 100 grains of dry soil : Let 

 the digesting go on for half an hour with occasional stirring. 

 Filter through a weighed filter paper, wash with distilled 

 water, until the water passing through ceases to give acid 

 reaction tested with litmus paper. Dry the whole at 25OF. ; 

 weigh the substance in the filter paper ; deduct the weight of 

 the filter paper. The loss of weight represents the amount 

 of lime. 



(3) The contents of the filter paper are now carefully 

 removed into a tall glass cylinder, and the impalpable 

 matter separated from the sand and coarser particles by 

 repeated washing with water. Stir well, let subside for 

 a minute and pour off the supernatant liquid. The im- 

 palpable matter thus separated is collected on a filter, 

 dried as before and weighed. The weight represents the 

 weight of clay. 



(4) The remainder is sand. 



62. Proceeding on the above method we can refer any 

 soil to Schubler's Table which is given below. 



