APPENDIX I. 

 THE METHODS OF SOIL ANALYSIS. 



How to Take the Sample of Soil. Owing to the variation in 

 composition of the soil at different depths it is particularly necessary 

 that the sample should always be taken to the same depth and with 

 a tool making a clean vertical cut. Samples taken with a spade are 

 of very doubtful value and do not justify any lengthy examination. 

 A suitable tool consists of a steel tube 2 ins. in diameter and 1 2 ins. 

 long, with a f-in. slit cut lengthwise and all 

 its edges sharpened fixed on to a vertical ^ 

 steel rod, bent at the end to a ring 2 ins. 

 in diameter, through which passes a stout 

 wooden handle (Fig. 31). A mark is made 

 9 ins. from the bottom so that the boring 

 process can be stopped as soon as this 

 depth is reached. On withdrawing the tool 

 the core of soil is removed by a pointed iron 

 rod. Five or six samples should be taken 

 along lines crossing the field so as to get as 

 representative a sample as possible ; the 

 whole bulk must then be sent to the labora- 

 tory. Samples should not be taken from FJG. 31. Tool for taking 

 freshly ploughed or recently manured land. Soil Sam P les - 



In very stony soils it is easier to use a 2 -in. auger, but this does 

 not, in our experience, yield as satisfactory a sample as the tool shown 

 here. 



A spud is useful for rapid preliminary inspection of waste land 

 to ensure that the sample is normal ; much disturbance of these soils 

 is sometimes caused by rabbks. 



For precautions to be taken in drawing the sample see Russell, 

 Journ. Bd. of Agric., 1916, 23, 342, and for a discussion of the 

 magnitude of the experimental error see Robinson and Lloyd, Journ, 



347 



