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LETTER OF TRANSMITTAL. 



To His Excellency Governor Henry M. Hoyt, chairman of 

 the Board of Commissioners of the Second Geological Sur- 

 vey of Pennsylvania : 



Sir : I have the pleasure to submit the Report of Progress 

 of the Survey in Susquehanna and Wayne counties, in 

 1880, by Prof. I. C. White. 



The principal feature of this report is its classification of 

 the Pocono and Catskill formations, with definite names 

 bestowed, virtually for the first time, on their sub-divisions, 

 or several groups of beds. 



This is an important step in the progress of American 

 geology. It has not been know that any such classical dif- 

 ferentiation of these thick deposits was practicable. Mr. 

 White has however succeeded in establishing numerous 

 fixed horizons, well defined both by lithological and palseon- 

 tological marks ; and when, during the field season of 1881, 

 he shall have traced the outcrops of these sub-divisions from 

 Pike county westward to the West Branch of the Susque- 

 hanna river, we shall be in condition to devise a pretty com- 

 plete nomenclature for the hitherto unnamed sub-divisions 

 of formations VIII, IX and X in middle Pennsylvania, where 

 their combined thickness varies from 10,000 to 12,000 feet. 



This great desideratum has been necessarily postponed 

 to the closing years of the Survey. 



I beg to call your attention especially to Mr. White's de- 

 scription of the flat-pebble conglomerates, and to the calca- 

 reous breccias, or cornstones, of the district reported on, and 

 to the importance of the latter named rocks to its agricul- 

 ture. 



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