262 
Transactions Texas Academy oe Science. 
Weitzel, E. S. 
boundary not determined. Two or three workable seams. “The upper 
seam (or middle one, as I understand, where three seams exist), is from 
18 to 58 inches thick, with a 2-inch slate parting in the center, and is 
being worked at San Tomas.” Opinion of J. Owen concerning the coal. 
“The lower seam in this field outcrops 4^ feet at Eagle Pass, several miles 
norithwest lof San Tom'as .and up the Rio Grande river, 'showing along 
both sides of the river for a distance of ten miles. The abrupt inclination 
of the stratum at this place carries it below the surface, and its eastern 
boundary could not be determined. The stratigraphical position of this 
seam is 600 to 700 feet below the ISTueces or San Tomas seam.” Reference 
to Mr. Owen’s measurements at the Hartz mines. 
The Lignitic Field. Reference to State Geologist Dumble. See First 
Rept. of Progress, Geol. and Min. Surv. of Texas, p. 20. 
420. W. H. 
The Dykes of Bandera County. 
Geological and Scientific Bulletin, Yol. I, No. 8. Houston, 
Dec., 1888. 
iDescription of a pyrite-bearing dyke near Bandera. 
Extract: “This vein or dyke is known to run in a straight line about 
twenty-five or thirty miles, aud there are beside it six or seven more 
running parallel with it, and a line ten miles long north and south would 
cut all of them.” 
421. White^ Charles A. 
On the Age of the Coal found in the Eegion traversed by the Eio 
Grande. 
lAiner. Jour, of Science, III, Vol. XXXIII, pp. 18-20. New 
Haven, Jan., 1887. 
“During the past few years many discoveries of coal have been made 
'within the region which is traversed by the lower portion of the Rio 
iGrande, besides those which were made by the members of the United 
•States and Mexican Boundary Commission and other early government 
expeditions. In Texas, coal has been found in 'Webb, Maverick, Presidio 
and El Paso counties; and in Mexico, in the States of Nuevo Leon and 
Coahuila. ,By certain local geologists and mining experts, whose reports 
have fallen under my observation, a part of these coals have been referred 
to Carboniferous age, and others to Triassic age. From personal examina- 
tion in the field, extending over a large part of the region in question, and 
an examination of fossils which have been collected by different persons 
from strata associated with the coals, I am satisfied, however, that none 
of them are earlier than late Cretaceous age. 
“In some cases the .coal of this region is worthless for practical use, but 
in others it is of good quality; all of it having the general characteristics 
of the coals which are obtained from the Laramie and Fox Hills forma- 
tions in Colorado, Utah, and Wyoming. From the data and observations 
just mentioned I do not hesitate to refer all the known coal of the region 
under consideration to one ©r the other, or both, of those formations.” 
