proceedings: geological society 361 



$200 per carat. Other crystals that have not yet been cut will probably 

 yield equally fine stones. 



The salt and gypsum deposits of southwestern Virginia: George W. 

 Stose. The deposits described are in the valley of North Holston 

 River in the vicinity of Saltville and are associated with a soft shaly 

 formation (Pulaski) of upper Mississippian age, 1000 feet thick. This 

 formation overlies the Price sandstone, which represents the Pocono of 

 Pennsylvania, and underlies the Newman limestone, which represents 

 the Greenbrier of that region. 



The gypsum was formerly considered to have been derived from lime- 

 stone by the action of sulfuric acid solutions derived from oxidizing 

 pyrite in the associated black shales, but more recently has been 

 described by Eckel as sedimentary in origin. The fact that the depos- 

 its are found only close to a great fault which overthrusts Cambrian 

 dolomite from the southeast upon the Pulaski formation, leads to the 

 present conclusion that the thick deposits of both gypsum and salt are 

 due to concentration in the Pulaski formation, by meteoric waters 

 circulating along the fault, of minerals originally disseminated in the 

 same formation by sedimentation under salt-pan conditions. Further 

 evidence in support of this view was presented. 



Classification of metalliferous mineral lands: R. W. Stone. A great 

 part of the work of the Metalliferous Board of the Land Classification 

 Board of the Geological Survey has been the classification of land in the 

 Northern Pacific Railroad grant. This grant made by Congress to the 

 Northern Pacific in July, 1864, to aid in the construction of a railroad 

 and telegraph line from Lake Superior to Puget Sound was a gift of 20 

 alternate square miles of non-mineral land on each side of the right of 

 way for each mile of road in the territories, and 10 alternate square miles 

 in the States. Two in lieu strips, each 10 miles wide, granted subse- 

 quently, made in the territories a strip of land 120 miles wide in which 

 the railroad had a claim to all odd-numbered sections of non-mineral 

 land. The first formal classification of these lands was provided for 

 by Act of Congress, February 26, 1895, the work to be done by three 

 commissioners in each of four land districts in Montana and Idaho. 

 Many of the classifications made by these commissioners were protested 

 and vacated as fraudulent. June 25, 1910, Congress made an appropria- 

 tion to complete the examination and classification of lands within the 

 Northern Pacific grant. This work was begun in July 1910 by Messrs. 

 Calkins, McDonald, Pardee, and E. E. Smith in Idaho and Stone in 

 Montana, all under the supervision of Mr. H. S. Gale, and was continued 

 in 1911. 



In the public domain and in Indian Reservations the classification as 

 mineral or non-mineral is based on a consideration of relative values, 

 agriculture, grazing, and timber possibilities being balanced against the 

 probability of paying mineral deposits. In the Northern Pacific grant, 

 "Is the land mineral or non-mineral?" is the whole question. The main 

 point of contention between the government and the railroad is the 

 interpretation of the law as to what constitutes evidence of mineral land. 



