to arrange them by elevation groups, in order to have the data in a form 

 useful to project considerations; (d) when mixed samples are used, analysis 

 of duplicates from the mixtures can provide a way to evaluate variability 

 in the results due to analysis procedure; and (e) the original unmixed 

 samples should be retained should additional size analysis be required 

 because of errors or because the original mixtures chosen do not provide 

 the appropriate information needed to solve problems later in the investi- 

 gation. 



45 



