12 NEW YORK STATE MUSEUM 



The c®pper shown by the analysis is probably present in the 

 pyrite. This mineral usually has the deep yellow color character- 

 istic of the copper-bearing variety. 



An analysis of the dike, which has also been reported by Mr 

 Wishart, is sufficiently interesting to deserve record. It establishes 

 the ultra-basic nature of the rock and is in agreement with the view 

 above expressed that it is an altered peridotite. 



Silica (SiOg) 35-50 



Alumina (AI2O3) 4.52 



Ferric oxid (FcgOs) 7.40 



Lime (CaO) 2.60 



Magnesia (MgO) 37-64 



Carbon dioxid (CO,) 1 i-? -^lo 



Water (H^O) j 



' " 100.96 



Arsenopyrite has been reported by Beck^ and Whitlock^ near 

 Edenville and at other places in Orange county and in the town of 

 Lewis, Essex co., 10 miles south of Keeseville. At the first named 

 locality it is associated with leucopyrite, the disarsenid of iron and 

 scorodite, a hydrous arsenate of iron; the wall rock is crystalline 

 limestone. 



CARBON DIOXID 



The production of natural carbonic acid gas as an industry is con- 

 fined to the vicinity of Saratoga Springs. There are no other locali- 

 ties in this country where the gas is recovered from natural sources 

 and marketed, though a large production is made by the decomposi- 

 tion of mineral carbonates, combustion of coke and in other ways. 



The companies engaged in this industry at Saratoga Springs 

 include the following: New York Carbonic Acid Gas Co., Natural 

 Carbonic Gas Co., Lincoln Spring Co., Geysers Natural Carbonic 

 Acid Gas Co., and the Champion Natural Carbonic Acid Gas Co. 



The phenomena of occurrence and the methods used in collecting 

 and storage of the gas for market have been described in the pre- 

 ceding issue of this publication. There have been no new features 

 in the industry during the past year, except that the production 



1 Mineralogy of New York. 1842. 



2 List of New York Mineral Localities, N. Y. State Mus. Bui. 70. 1903. 



