LAURENTIAN MAGNETIC IRON ORE DEPOSITS 

 IN NORTHERN NEW YORK. 



To Prof. James Hall, Director of the New York State Museum of Natural 

 History, Albany, N. Y. : 



Sir — For several years past the subject of the Laurentian Magnetic Iron Ore 

 Deposits in Northern New York has occupied my attention. My intention in 

 the following pages is merely to state a few facts which have come to my notice, 

 and for the present reserve a longer and more detailed report. 



I have not been able, from any of the reports on the geology of New York, 

 to draw any general conclusions with reference to the geological structure of the 

 district under consideration ; indeed, this seems still to be an exceedingly com- 

 plicated question. I shall endeavor to explain what I have seen, and possibly 

 aid others in their researches. 



The Laurentian of Canada has been divided by Sir W. E. Logan into the 

 Lower Laurentian, and the Upper Laurentian or Labrador Series. In the 

 Canadian reports we find that the Upper Laurentian is acknowledged to rest 

 uncomformably upon the Lower Laurentian. We have in Northern New York 

 these two groups of rocks characterized by their mineralogical peculiarities, and 

 we have proof of their unconformity. There are, however, several series of 

 rocks in the eastern portion of the Adirondack region, or that portion bordering 

 Lake Champlain, in the townships of Moriah, Crown Point, and Ticonderbga, 

 which undoubtedly deserve separate consideration. 



The Lower Laurentian, or that series containing the workable beds of mag- 

 netic ore, is without doubt the lowest of the series exposed in this region. Its 

 area and distribution I have, from the first of my work, endeavored to trace, as 

 it is of the utmost economic value. My data for the present are based on 

 limited observations at various times during the last four years, and not extend- 

 ing over any very great area, being confined to Essex county, and particularly 

 to a few of the townships of that county. Some facts which I have been able 

 to establish may, in time, lead to the completion of a geological map and a 

 solution of the geological structure. 



The mountains throughout the eastern portion of Essex county lie in ranges 

 extending in a northeast and southwest direction, and indicate lines of upheaval. 



The following streams indicate in a general manner the direction of the 

 uplifts : the east and west branches of the Ausable river and Boquet, the Black 

 river, draining to the northeast, and the Upper Hudson river, Boreas river, 

 Schroon river, flowing to the south. 



These streams may be divided in the following manner : the west branch of 

 the Ausable river, from Wilmington southwestward through North Elba and its 

 head waters into the Indian Pass, forms a general northeast and southwest line 

 with the course of the Upper Hudson, originating in the Indian Pass and flow- 

 ing southward through Lake Henderson, Lake Sanford, and continuing in an 

 almost due-southward direction as far as Tahawus. Along this line are the 

 abrupt mountains, " White Face " and " Wall Face." 



The eastern branch of the Ausable extends from Ausable Forks southward 

 and a little west through Upper Jay, Keene, Keene Flats, and southward by 



