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         <center>The Dry Sieving Method</center>
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<font face="Arial" size="2" color="black">The most common and widely accepted method of separating sand- and 
gravel-sized material into classes is by the use of wire-mesh sieves.<br>
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First, a bank of sieves is assembled consisting of a pan and the 3, 2, 1, 0, and -1 phi sieves arranged with the finest mesh on the bottom. It is not important whether the analyst uses Wentworth or phi scales for the sieve sizes as long as the interval between the sieves brings out the continuous nature of the frequency distribution.<br>
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A sample of about 40 grams or less is introduced into the top of the bank, the cover is attached.<br>
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The bank is placed into a mechanical shaker.<br>
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After agitation for 10 to 15 minutes, the bank of sieves is removed from the 
mechanical shaker, and the sieves are separated.<br>
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If material is retained on the -1 phi sieve, than gravel is present in the sample 
and the procedure must be repeated with a bank of gravel sieves to analyze 
that fraction.<br>
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Each sieve that contains some sample is, in turn, emptied individually onto a large sheet of paper. Brushing and tapping the sieve on the flat work surface ensures that all of the sample has been dislodged from the sieve.<br>
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The sediment is transferred to a tared beaker.<br>
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The beaker with sample is weighed and the weight is recorded. The 
recorded weights of the phi sizes are added and normalized to determine the 
frequency distributions within the sand and gravel fractions.<br>
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