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facts concerning them as would enable the owner or prospector to form any definite idea of their relations or probable values.

The following statements are based for the greater part on the work of myself and associates of the present Survey (although all reliable sources of information accessible to us at present have been examined), and many of the facts will be found stated in much greater detail in the various papers accompanying this and preceding Annual Reports, to which the reader is referred.

FUEL AND OILS.

WOOD.

Over Eastern Texas the amount of wood suitable for fuel purposes is seemingly inexhaustible; but as we go west it grows less and less, until in many places mesquite roots or even the "Mexican dagger" are the principal source of supply. The investigations of the Survey up to the present have been confined to an examination of the wood supply of certain counties with reference to the manufacture of charcoal for iron smelting, and this will be more fully discussed in Part II of this Report, "Report on the Iron Ore Region of East Texas." Other facts are also given in other parts of the Report

LIGNITE.

Intermediate between peat and bituminous coal we find a fossil fuel known as lignite or brown coal. It contains less water and more carbon than peat, but has more water and less carbon than bituminous coal. Lignites are the product of a later geologic age than bituminous coal, and the bituminous matter has not been so fully developed as in the true bituminous coal.

Lignite varies in color from a brown to a brilliant jet black, and occurs in all degrees of purity, from a lignitic clay to a glossy coal of cubical fracture. The greatest amount of our lignites, however, are of black color, changing to brownish black on exposure, often with somewhat of a conchoidal fracture and a specific gravity of about 1.22.

Lignite occurs in beds similar to those of bituminous coal, although they are not always as regular and continuous.

LOCALITIES—The area in which the lignites occur in Texas was defined in general terms in the First Report of Progress, p. 20, as follows:

"The lignite field is by far the largest field we have, and the coal strata it contains are of much greater thickness than those of either of the others. As