GRIMSLEY. | Flistory and Distribution. 29 
culiar taste, received in flowing for one hundred miles over a 
eypsum formation, which he described as follows: 
‘‘T have traced this gypsum belt from the Canadian river in a southwest direc- 
tion to near the Rio Grande in New Mexico. It is about fifty miles wide upon the 
Canadian, and is embraced within 99° and 100° meridians of west longitude. 
Wherever I have met with this gypsum I have observed all the varieties from 
common plaster of Paris to pure selenite. I regard this gypsum belt as a very 
prominent and striking feature in the geology of the country. From its uniform- 
ity and extent, I do not think there is a more perfect and beautiful formation of 
the kind known. I have myself traced it about three hundred and fifty miles, 
and it probably extends much farther. . . . The only deposits known to me 
as more extensive are those in South America, described by Darwin in his geology 
of South America. Very probably the ancient igneous agency in the Wichita 
mountains, and along a line southerly to the Rio Grande may have been con- 
cerned with the production of the gypseous deposit of the same region.’’ 
In.Texas, Dumble” reports valuable gypsum beds in the lower 
Comanche series of Burnet county, Texas. In the Permian, 
the beds are numerous and often of considerable thickness. 
The clay is traversed in every direction by seams of fibrous 
gypsum, varying in thickness from paper-like seams to 10 feet, 
while the compact gypsum reaches 25 feet. 
‘In places a large deposit of gypsum appears, which on the surface consists of 
a loose material ready to be shipped as fertilizer without grinding. Below this, 
erystalline gypsum appears in thickness of several hundred feet. This and the 
selenite deposit will make excellent plaster of Paris, and the finer granular va- 
rieties are fit for works of art.”’ 
The valuable deposits of northern and western Texas, Dumble 
believes were deposited in an arm of the sea cut off from the old 
Permian ocean. ‘The rock is used for: plaster of Paris, wall 
plaster, and fertilizer. The fertility of the river valleys is re- 
garded as due in part to the fact the rivers have their sources 
in the gypsum beds. 
Gypsum in California!? and Rocky Mountain States. 
At Coalinga, Cal., a 10-foot stratum of gypsum has been 
mined since 1892, and sold as fertilizer in Tulare and Fresno 
counties. Inthe latter county, near Mendota, is the Paoli mine, 
discovered in 1892. The gypsum on the crest of the ridge at 
Paoli mine is at least 30 feet thick, and there is some indication 
12. First Annual Report, pp. 123, 188, 193. Second Annual Report, pp. 455, 456, 700. 
13. California State Mining Bureau Bull. 3, p. 63, 1894. 12th Report State Mineralogist of Cali- 
fornia, pp. 323-825, 1894. 
