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In 1874, the Big Bonanza of the Nevada was discovered, at a depth of more than 1500 feet, where the amount of ore in sight has been estimated at from $60,000,000 to $1,500,000,000. To this is owing, in a great measure, the large yields of Nevada given in the above table.

I have given these statements of the value of the mining interests of the country for the encouragement of the mining industry of western Texas. Such veins as those of Presidio and El Paso counties rarely become poorer on going deeper.

About five miles northeast of the town of Mason are some silver mines, which, at the time of our visit, about the first of last June, were being worked by Messrs. Thompson, Wood & Morrill. Vein at top, twelve to fourteen inches thick ; at the depth of forty-two feet, its-thickness is nine feet. It is mostly calcite, dipping at an angle of about forty-five degrees. Its upper wall is a layer of mica schist, about sixteen feet thick, quartoze granite beyond and also below the vein. The silver is in small grains, disseminated in gray limestone. Mr. Thompson told me that he had obtained specimens which assayed $300 to the ton. Those which I saw will give a much less yield.

In the eastern part of Mason county, on land belonging to C. R. Johns & Co., are said to be large veins of silver ore. Specimens of this ore I have seen which assay from $14 to $16 to the ton. The gangue is granular epidote in a quartoze rock, through a portion of which is scattered the granular silver.

I have a small specimen of copper and silver ore from a vein said to be two feet thick, which has been traced to the distance of three miles or more. So says Dr. C. S. Smith, of the town of Llano, through which the vein is said to extend. This specimen has a large per cent. of silver and also of copper. If enough of such ore is there, it will be very valuable, and give a new impetus to mining in Llano county. I am indebted to Dr. Smith for these and other valuable specimens. The vein is in the metamorphic rock of mica schist in the granitic region.

In the western part of Burnet county, about three miles from the town of Bluffton, are lead ores (galena) in the