Trans. N. Y. Ac. Set. 14 Oct. 29, 



The President then gave a description of the geological structure 

 at Ontonagon, in the Keweenaw peninsula, of the Porcupine Moun- 

 tains, the distribution of the Potsdam sandstone, and of the underlying 

 rocks, the Copper series, which in the Eastern States are represented 

 by the Taconic or Cambrian slates, and on the north side of Lake 

 Superior by the Anemikee rocks of HUNT. 



Mr. C. Van Brunt referred to an ancient mining excavation along 

 the south wall of a vein at Houghton. From this trench much copper 

 had been extracted by the old miners, and charred remnants of wood 

 and many stone tools were found at the bottom. 



The President remarked on the ancient works of the Lake Superior 

 region, which were much more extensive, notwithstanding the imper- 

 fect means and absence of machinery at the disposal of the prehistoric 

 miners, than those of the whites, by whom these veins have been 

 worked only since about the year 1847. The guide of the early ex- 

 plorations of the latter has been, almost invariably, the ancient works, 

 mounds, and excavations of their prehistoric predecessors. The 

 old works were never deep. The tools employed were rude stone 

 mauls, sometimes very heavy, which were attached to handles by 

 withes around a groove at the middle, and were slung by several 

 persons : others were much smaller, and were handled by a single 

 person. He had seen but one copper mining-tool which had been 

 fashioned and used by them. The President also described the 

 glacial phenomena of the Ontonagon region — the polish and striation 

 of outcrops, abundant boulders, etc., and then referred to some of the 

 most interesting papers recently read at the Minneapolis meeting of 

 the American Association for the Advancement of Science. The 

 papers of Mr. Wm. McAdams were particularly important, describ- 

 ing his discoveries of the bones of some large, new fossil fishes in the 

 Carboniferous limestone at Alton, 111., the skull of the giant beaver 

 {Castor aides), etc., in the Quaternary, and a large number of bones 

 and teeth found at the bottom of the Loess or Bluff Formation ; these 

 last remains are likely to throw great light on the true character and 

 history of the Loess. 



October 29, 1883. 

 Section of Chemistry. 

 The President, Dr. J. S. Newberry, in the Chair. 

 Thirteen persons present. 



Prof. D. S. Martin exhibited a specimen of the ashes thrown 

 out at the remarkable eruption of the volcano Krakatoa, in Java, 

 during last August. 



