ROGERS, GEOLOGY OF THE CORTLAXDT SERIES 13 



erable room for error ; and it is to be understood that the various bound- 

 aries are probably not always exactly where they are drawn on the map, 

 although never far away. 



The massive character of the rocks precludes any topographic structures 

 of particular interest. The weathering of the rocks is like that in all 

 other such regions ; in the case of the olivine rocks alone is there anything 

 worthy of mention, and this will be taken up under their description 

 (Plate III, Fig. 1). The most striking valley in the district is that in 

 which lies the long curved tongue of schist, projecting north into the 

 series ; it is due, however, to a line of weakness along the contact and not 

 to the igneous rocks themselves. In like manner, Lake Meahach, a stag- 

 nant inlet, seems to occupy a similar, though much less pronounced de- 

 pression. Aside from these instances, the region is a succession of appar- 

 ently irregular hills and valleys, becoming to the east rather wild and 

 beautiful in a small way. 



Historical Eeview 



Considerable work has been done on this small district, and the evolu- 

 tion of our present ideas concerning it is interesting. Each of the earlier 

 workers expresses a different view, which have been regarded since Wil- 

 liams's work as antiquated; yet it seems that some of these theories are 

 not entirely to be cast aside, after all. 



It is a very curious and interesting fact that the emery in this district 

 was first seen and recognized by the first white man to ascend the river. 

 The following passage is taken from Henry Hudson's report : 3 "The 

 Mountaynes looke as if some Metall or Minerall were in them. For the 

 Trees that grow on them were all blasted, and some of them barren with 

 few or no Trees on them. The people [Indians] brought a stone aboord 

 like to Emery (a stone vsed by Glasiers to cut Glasse) it would cut Iron 

 or Steele : Yet being bruised small, and water put to it, it made a colour 

 like blacke Lead glistering: It is also good for Painters Colours. At 

 three of the clocke they departed, and we rode still all night." This trans- 

 action took place on his voyage down the river ; and we read further that 

 he descended eighteen leagues below this and was driven by the Indians to 

 the shelter of a "Cliffe, that looked of the colour of a white greene." This 

 was opposite Manhattan Island about two leagues below what is probably 

 •Fort Washington Point; it was probably, therefore, the Castle Point 

 (Hoboken) serpentine. This would show that the emery was brought 



* "The third voyage of Master Henry Hudson," New York Historical Society Collec- 

 tions, (1), I, 143. 1809. 



