Record of Geology of Texas, 1887 - 1896 . 
85 
Dumble, Edwin T. 
miles. The northern boundary has not yet ibeen determined. It contains 
two workable seams of coal, and locally, at least three. These differ 
somewhat in cliaraoter; the lower is a .SeminBituminous coal, probably of 
iCretaceo'US age, which, so far as it has been examined, gives promise of 
being a very good fuel, fft is being worked north of Eagle Pass at the 
Hertz mines. The other bed now being worked at San Tomas, is possibly 
of the Laramie group. It is somewhat lignitic, although quite different 
from the lignites of our Tertiary coal field. Another variety which is 
also found in some quantity in this coal field is albertite. This seam is 
northeast of the San Tomas exposure, and will prove valuable. 
“The Lignite field is by far the largest, and the coal strata it contains 
are of much greater thickness than those of either of the others. As nearly 
as its boundaries oan now be marked, they are as follows : Beginning on 
the iSabine river, in (Sabine county, the boundary line runs west and south- 
west near Crockett, Navasota, Ledbetter, Weimar and on to Helena anot 
the Rio Grande river; thence back by Pearsall, Elgin, iMarlin, RRliland, 
(Salem, and Clarksville to (Red river. It includes fifty-four counties in 
whole Oil’ in part, and while the ocourrence of lignite has not been noted 
in every one of these, it .will in all probability be found in lall of them 
sooner or later. Eour, possibly five, strata of lignite can be recognized in 
this field, one of which attains in many places a thickness of from 15 to 
20 feet. The amount of sulphur contained in these lignites is very varia- 
ble, as is indeed the quality of the lignite itself. In some places there is a 
good clean lignite, almost, if not entirely, free from sulphur, while at 
other places masses of sulphuret of iron are mingled through a carbona- 
ceous mass.” Pp. 368-369. 
For outline of remainder of this report, see Ash'burner, Charles A. 
(Coal in Texas), Min. Resources of U. 'S. for 1888. 
119. 
Appendix to Preliminary Report on the Soils and Waters of 
the Upper Rio Grande and Pecos Valleys in Texas/'^ by H. H. Har- 
rington. 
, Geol. Surv. of Texas, Bulletin No. 2, pp. 24-26. 1890. 
The effect of alkalies upon crops. The Experimental Farm above Pecos 
City irrigated by the waters of the Pecos river. .Soils: Salt and other 
determinations by L. E. Magnenat. IRock material from which the soil 
is derived feldspathic. Apparent excess of alkalies not dangerous to agri- 
culture. 
“On ipage 10, Prof. Harrington makes this statement in regard to the 
effect of alkalies on the growth of crops: ‘But s.o far as I oan ascertain, 
the maximum quantity of alkali that any crop would tolerate and still 
thrive and do well has not yet been determined. The character of the 
soil would undoubtedly have great influence in this matter.’ Such being 
the case, I have delayed thb publication of this Bulletin that additional 
facts might be accumulated bearing upon this point, for it is one of the 
greatest importance to a large area in the Pecos Valley. 
“Both before and since the eommeneement of this examination there has 
been au experimental farm in operation above Pecos City, using the waters 
