4 BULLETIN 574, U. S. DEPARTMENT OF AGRICULTURE. 



Referring to Table II (p. 14), follow down the first column to the 

 figure 8.0 (the weight of the separation of damaged corn in grams). 

 The figure opposite (in the second column, with heading 240) is 

 found to be 3.3, which is the correct percentage expressed in the 

 nearest tenth of 1 per cent. 



The use of the table will save time in converting the separations 

 into terms of percentages of the whole sample analyzed, and its 

 careful use will prevent errors which often occur in the mathematical 

 calculations involved. 



In this connection it is highly essential that extreme care should 

 be taken to preserve accurately the character of the original sample 

 when reducing the original 2\ or more pints taken from the bulk 

 grain to the smaller sample of approximately 40 grams for wheat or 

 approximately 250 grams for corn for analytical purposes. Experi- 

 ments have shown that it is almost impossible to divide a large sam- 

 ple into smaller portions and at the same time retain the correct pro- 

 portion of damage, dirt, color, etc., in the smaller sample unless a 

 device similar to the one described in Bulletin 287 of the United 

 States Department of Agriculture is used. This apparatus was de- 

 vised to meet the demands of grain and seed dealers, as well as 

 laboratory workers, for securing a reliable grain or seed sample from 

 a larger portion of the material to be examined, analyzed, or graded. 

 Figure 1 shows a vertical cross section of the sampling device, while 

 figure 2 shows a cross section of this device at the base of the cone. 

 A detailed description of this sampling device is contained in the 

 before-mentioned bulletin. This device has been covered by a public- 

 service patent (No. 1,160,036), and anyone in the United States is 

 free to make and use it without the payment of a royalty. 



