walcoW.J NORTHERN APPALACHIAN DISTRICT. 91 



APPALACHIAN PROVINCE. 



The Appalachian Province includes the outcrops of Cambrian strata 

 on the line of the Appalachian system of mountains, from the lower 

 St. Lawrence Valley on the north, to Georgia and Alabama on the 

 south. 



For the purpose of presenting the historical data the province will 

 be divided as follows: 



A. Northern Appalachian district. 



B. Southern Appalachian district. 



NORTHERN APPALACHIAN DI8TRICT. 



The northern Appalachian district includes the Hudson River and 

 Lake Ohamplain area east of the river and lake and an extension 

 northeastward into Canada, as far as the vicinity of Cape Rosier on 

 the St. Lawrence River. 



The Hudson River and Lake Cham plain area will first be considered. 

 It includes the strata referred to the Cambrian, found on the western 

 slope of the Green Mountains, the foothills and the more level country 

 stretching westward toward the Hudson River and Lake Ohamplain. 



The earliest reference in the literature to a distinct formation that is 

 now referred to the Cambrian is found in a description of the geology 

 of western Massachusetts and eastern New York. On this account this 

 formation, the " Granular Quartz," will be treated historically as it 

 has been mentioned by authors in Massachusetts, New York, and Ver- 

 mont, until the year 1861, when its history will be carried forward with 

 that of the "Red Sandrock" and the "Georgia Slates," with which 

 it was then correlated. 



GRANULAR QUARTZ. 



The first differentiation of a formation referred to the Lower Cam- 

 brian in America was made by Prof. Amos Eaton in 1818. x Prior to 

 that time Mr. William Maclure, the pioneer of systematic geology in 

 America, published a map with descriptions of the rocks of the Eastern 

 United States, in which all the strata now referred to tlie Cambrian 

 system in the Appalachian range were included in the Transition series. 

 On his first map 2 the Transition rocks are represented as extending 

 from Hudson, in the valley of the Hudson, south to the vicinity of 

 Poughkeepsie, and thence southwest throughout New York, New Jersey, 

 Pennsylvania, Virginia, eastern Tennessee, northern Georgia, and 

 into Mississippi. On the map accompanying a later work 3 the Transi- 



1 An index to the geology of the Northern States, with a transverse section from Catskill Mountain 

 to the Atlantic. Leicester, 1818, pp. 52. 



2 Observations on the geology of the United States explanatory of a geological map. Am. Phil. Soc. 

 Trans., vol. 6, 1809, pp. 411-428, map. 



Observations of the geology of the United States; with remarks on the probable effects that may 

 be produced by thft decomposition of the different classes of rocks on the nature and fertility of soils, 

 With a map and two plates. Am. Phil. Soc. Trans., new ser., vol. 1, 1817, pp. 1-91. 



