The Publishers and the Author will be grateful to 

 any of the readers of this volume who will kindly call 

 their attention to any errors of omission or of commission 

 that they may find therein. It is intended to make 

 our publications standard works of study and reference, 

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 Publishers to see them removed immediately upon being 

 discovered, and it is therefore desired that the Author 

 may be aided in his task of revision, from time to time, 

 by the kindly criticism of his readers. 



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