IN ESSEX COUNTY, MASS. 135 



of those wliose hearts were touched with the beauties and 

 wonders of nature, and who wished to sit in her school as 

 humble disciples. 



They were observers, with the true passion for knowl- 

 edge, — explorers, whose zeal carried them through many 

 difficulties and hardships, and rewarded them with many 

 brilliant discoveries. Such were the early workers in the 

 field of geology in this county. 



The Essex County Natural History Society and its suc- 

 cessor, the Essex Institute, have given their attention 

 almost wholly to botany, zoölogy and prehistoric archae- 

 ology, owiiig to the bent and profession of their leading 

 members. In these directions they have given the Essex 

 Institute and the Peabody Academy of Science a world- 

 wide reputation. Had the same thorough and continuous 

 work been done in the fields of which this paper treats, I 

 believe that results hardly less brilliant and helpful to sci- 

 ence would have been realized. 



The geology of Essex County is not rieh in metalliferous 

 deposits, nor even as far as we know in valuable minerals ; 

 but both Rockport and Newburyport have yielded sur- 

 prises to the older mineralogists, the former giving two 

 new species to the science. Dana gives but eight towns 

 in our county as mineral localities, one of which, the 

 sodalite of Salem Neck, is only a reminiscence. Other 

 localities have been named by Hitchcock and others, but 

 little has been taken out of them. For instance, the evi- 

 dence for the existence of the Topsfield copper mine rests 

 at the bottom of the Atlantic. GeoWical and mineraloof- 

 ical investigation has been pursued here in a desultory 

 way. 



In the first three volumes of the Proceedings of the 

 Institute are preserved the accounts of the early labors in 

 this department. I will now briefly review them. Two 



