CHAPTER XXXIII 



MANURING 



WHEN it is desired to take samples of soil and have them 

 tested by a chemist, care should be taken to ensure that 

 the samples are really representative of the soil as a whole. 

 The remains of a dead animal, the accidental presence of a small 

 patch of some mineral, or other adventitious circumstance, 

 may cause the analysis to be most misleading, unless proper 

 precautions have been taken. 



A very simple method of taking representative samples is 

 to bore holes in the soil to the depth of, say, a foot and a half, 

 with an ordinary auger, and to remove and place in a canvas 

 bag all the soil that clings to the auger. When ten or a dozen 

 of such samples have been taken in different parts of a field, 

 and well shaken together, the bulk sample is generally fairly 

 representative of the whole and not so likely to mislead an 

 analyst. 



It is well, however, that planters should be able to make 

 some simple and yet very informative tests for themselves. 

 Acidity of the soil can be easily detected by the use of small 

 pieces of litmus paper, which can be obtained from any chemist 

 for two or three pence. This litmus paper is manufactured 

 by dipping a specially-prepared paper in a solution of litmus. 

 It has the peculiar property of turning to red when in contact 

 with acid. If the litmus paper is inserted into the middle of a 

 handful of soil and turns red, it is a sign that the soil is acid. 

 The acid might be the harmless carbonic acid always present in 

 the soil, but in that case the carbonic acid would volatilize 

 as the paper dried. If the paper remains red when dried it is a 

 proof that the soil contains fixed acids or acid salts and should 

 have an application of lime to correct the fault. 



Hydrochloric acid is constantly used by agricultural chemists 

 in testing for the presence of lime in the soil. If, when a few 



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