Record of Geology of Texas, 188'7-1896. 
85 
Comstock, Theo. B. 
ity in Mason county not yet critically examined. A large inclusion was 
found in quartz, and the occurrence of tungsten and niobium was also 
noteworthy. A special ‘trip was made to the neglected region. The report 
'of Mr. George Durst as to the existence of old furnaces was verified. Slag 
at one place was said to contain globules of silver. Careful examination 
showed the inclusione to be tin, not silver, and that the whole slag carries 
/abundant traces of tin. A detailed description of this district is found in 
the Second Ann. Kept, of the Geol. Surv. of Texas, pp. 595-602. 
The tin territory is defined as a tract fifty miles long, ten to fifteen 
wide, extending from western Burnet to eastern Mason across the center 
of 'Llano county. 
The above announcement called forth a statement by “G. A. F.” that 
tin had previously been found, in 1866, twenty miles south of Gonzales, 
and, in 1867, at two localities on the Nueces river. He also states that 
tin had been found in Llano county in 1877. Eng. and Min. Jour., LI, p. 
229. Feb. 21, 1891. 
Tin in Central Texas. 
Correspondence. 
Engineering and Mining Journal, Vol. LI, p. 281. F. Y., 
March 7, 1891. 
A reply to “G. A. F.” 
“Two instances reported by him are from South Texas, beyond the 
limits 'of my investigations, and both of them appear to have been hereto- 
fore unrecorded. ‘ The localities are both in the Tertiary Area, from which 
the discovery only of drift or secondary deposits of little commercial value 
can ever be anticipated.” 
Occurrence of 'Tin in iCentral Texas. 
American Journal of Science, III, Vol. XLI, p. 251. Yew 
Haven, March, 1891. 
In a note bearing the above title, dated January 24, 1891, Professor 
'Comstock makes a statement concerning the discovery of Cassiterite in 
Central Texas. 
Report of. 
Second Ann. Rept. of the Geol. Surv. of Texas, 189,0, pp. xciv- 
xcviii. Austin, 1891. 
Administrative report of the Geologist for Central Texas for 1890. Ex- 
ploration of a district (Wichita Mountains) in Indian Territory with Mr. 
iCummins., Personnel of the field party for thg Central Mineral Kegion. 
Character of the region traversed. Method of survey adopted. Office 
assistants. Topographic work of Mr. J. C. Nagle. Work of Mr. Charles 
Huppertz, geologic aid. Work of Messrs. Jones and Clark. The Con- 
