140 Thirty-second Report on the State Museum. 



NORTH HUDSON AND NEWCOMB. 



I have not studied this region, but from the few observations I have made 

 and facts I have gathered, there is no doubt that the entire region may be con- 

 sidered as belonging to the Labradorite series, with limestones probably of the 

 same group as those in Minerva township. The iron ores which have been de- 

 veloped in Newcomb are all titaniferous. 



As for the remaining townships, I would merely state that there are not facts 

 enough as yet collected to make it worth while to theorize. Magnetite has been 

 reported found at many places. Magnetic iron occurs at Long or Edmond's 

 pond, in Keene township. It has also been found in the neighborhood or along 

 the east branch of the Ausable river. Whether this river flows along an eroded 

 anticlinal fold or not remains to be proved. 



North Elba, St. Armand and Wilmington townships are undoubtedly occu- 

 pied by the Labrador series. 



Since the above was written, I have learned sufficiently of the relations of 

 the crystalline limestone to state that it rests unconformably upon the Upper 

 Laurentian rocks ; and the entire group of crystalline limestones, with its asso- 

 ciated decomposing gneisses, will probably be proven to be a newer series of 

 rocks resting unconformably upon the Lower and Upper Laurentian. 



I had hoped to have some maps of the iron-ore mines, but they are not ready 

 for publication. 



The accompanying map is subject to many alterations, and is only prelimin- 

 ary. Without doubt, further investigation will change the present assumed 

 areas. 



I am yours very respectfully, 



CHARLES E. HALL, 

 Assistant to the Second Geological Survey of Penn. 

 Philadelphia, October — , 1879. 



