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commercial value, there will be little difficulty in obtaining it in abundance. At present, transportation facilities are inadequate for any considerable industry, and the best deposits are near the summit of very dry ridges. A large quantity was mined several years ago, but for some reason the property has been abandoned, temporarily it is claimed by residents in the district.
ASPHALTUM.
The ashpaltum belt, or basin, is also roughly coincident with the area of basaltic outcrops, but the deposits are more narrowly restricted than the other economic products which seem to be more or less intimately associated with the eruptive tracts. I have no knowledge of any discoveries of this material outside of Uvalde county. The only tract which came under my personal inspection forms part of what is known as Debrill's ranch, on Turkey creek, about three and one-half miles below Cline. Here a tract of some twenty acres exposes what appears to be a thick layer of Cretaceous rock highly charged with bituminous matter. The rocks appear at first sight to be much disturbed, but closer inspection shows that a semi-fissile or roughly concretionary structure has been induced by weathering and by the irregularly crowded fossils which make up a large part of the limestone. As if produced by the organic matter of these fossils, the porous rock is also filled with the asphaltum which oozes out through the crevices and upon surfaces exposed to the sun. Freshly broken rock from greater depth show less of this at first, but it soon becomes apparent on exposure to the dry air. The percentage of the asphalt is large enough to make it profitable to handle the product commercially, although but little as yet has been attempted in this direction. This deposit has all the prominent characteristics of the famous beds of the Val de Travers, and from its mode of occurrence here, it is almost certain that continuations of the bed will be found by intelligent search. A very similar outcrop is known further south and reports have come in of others in different directions. This is only another instance of the value and necessity of accurate knowledge of geology in systematic exploration for mineral wealth. By familiarizing oneself with the beds above and below this horizon and tracing them where they lead, no doubt one might readily ascertain the exact continuations of these deposits and unearth extensive accumulations of the same material. A good practical geologist familiar with such products should have little difficulty in pointing out such places in which to mine the product.
COAL, OR LIGNITE.
The lignite field, so far as it lies within the limits of our survey of 1891, is confined to a comparatively narrow tract extending across the"
The term lignite is used here in accordance with the American usage classing all coals of later age than the Carboniferous as Lignite. E. T. D..