SAMPLING OF FERTILIZERS II 



of apples and other fruits. In such sampling 1 care must be exer- 

 cised not to select the particular individual to be sampled, but to 

 take every one which comes within the prescribed limit. In 

 general, it may be said that it would be advisable to divide the 

 materials which are the usual subjects of analysis into different 

 classes and subdivisions, and that uniform methods for these 

 classes and subdivisions be recommended. 



14. Sampling of Fertilizers. Perhaps there are no more numer- 

 ous and perplexing questions connected with the subject of 

 sampling than those which arise in the case of fertilizers. In 

 many countries the method of sampling the fertilizing materials 

 i ; ; prescribed by law. It is impracticable to give definite direc- 

 tions in all cases which will be applicable to all kinds of materials 

 and in all instances. The chemist himself having charge of secur- 

 ing the sample should see that it accurately represents the total 

 amount of the material sampled. Too often the samples which 

 are brought to the chemist have been secured without his advice or 

 direction and really are not representative. 



For sampling manufactured fertilizers, which in this country 

 are usually very finely divided, I have found nothing better than 

 a slotted brass tube. The tube may be from I to i l / 2 inches in 

 diameter, with a half or three-quarter inch slot. It should be 

 long enough to reach the full length of the package, and the lower 

 end should be provided with a cutting edge that it may be forced 

 into the package easily. For a handle a smaller tube 3 to 4 inches 

 long is brazed at right angles to the upper end of the larger tube. 

 In sampling, the package of fertilizer is thrown on the side, and 

 if the contents are hard they are broken up by rolling and by 

 blows on the container. The slotted tube is now forced into the 

 package with the slot down, turned over, shaken slightly to fill 

 the tube, withdrawn, and the content emptied on a rubber or oil 

 cloth. Samples are drawn from at least five per cent, of the pack- 

 ages, but should always be drawn from at least three packages. 

 These samples are thoroughly mixed on the oloth, a subsample 

 secured by quartering, placed in a screw-top can and labeled 

 for identification. This instrument and method are suitable for 

 sampling all finely ground fertilizers and fertilizer materials, but 



