PREFACE. IX 



In conclusion, I tender my thanks to those who have assisted nic in this 

 survey. Mr. G. H. Smith of Rochester, and Mr. W. M. Smith of ManUus, are 

 entitled to my acknowledo^ments for their services in the winter and spring 

 of 1846. Messrs. G. Geddes, H.S.Randal and L.F.Allen, have assisted 

 me in many ways. David Thomas is entitled to a similar acknowledgment; 

 for I have not hesitated to ask his advice on many doubtful questions, and 

 have always been kindly and frankly responded to. I have already given 

 the names of the two gentlemen who have been so efficient in the laboratory, 

 and who are still zealously engaged in chemical analysis. Mr. J. Crary, a 

 young chemist of Washington county, has also aided me considerably in the 

 work of analysis. To Mr. J. Paterson, who has superintended the proof- 

 sheets, the volume is in a great measure indebted for its general correctness. 



E.EMMONS. 

 Albany, December 30, 1846, 



