1879.) Texas in its Geognostic and Agricultural Aspect. 381 
chalk, for it is everywhere much cleft, and the rain falling on the 
ground finds its way slowly, therefore, partly through the rocks, 
into the cavities, It can accumulate in large quantities in these 
hollows ; the water must necessarily find an outlet again, and thus 
it is probable that the above-named rivers come from one or more 
subterranean lakes, and hence their uniform force, temperature 
and clearness. The water of these springs holds a great deal of 
carbonate of lime in solution, which shows that in the course of 
time the cavities are more and more enlarged; this view opposes 
at the same time the opinion that the water takes its origin in the 
Staked Plains of North-western Texas; if this were the case they 
must contain not only the carbonate but also the sulphate of lime 
in considerable ees since gypsum is extensively diffused 
_ there. 
Passing now to the Highlands, which embrace the whole re- . 
_ Maining part of Texas; it is the largest but the least satisfactorily 
known. The tertiary formation is very little diffused, and hence 
the soil is mainly derived from primary and secondary deposits. 
Nowhere are found extensive tillable and continuous tracts as in 
the Hill-country; the good planting-ground is mostly confined to 
the river-bottoms and valleys; only in particular counties are 
larger tracts of tillable land to be obtained. As already remarked, 
this high table-land is mostly rocky, dry, and sterile; but owing 
to good meadow-grounds, it is particularly well adapted to cattle- 
raising, which therefore is followed in a very extensive manner. 
ibis Highlands have, however, for Texas a particular impor- 
tance in other respects; it is mainly there that mining will, in 
future, be prosecuted. 
As regards the evidences of mineral wealth, we need not, for 
known reasons, look for them in the surface of the Lowlands. 
The whole of the Hill-country encourages no hope of rich mineral 
treasures. Throughout this entire division, however, coal has 
been discovered in many places; but, according to all scientific 
principles and personal observations, I must declare that there has 
been found no coal belonging to the genuine coal-formation ; but 
only such of the tertiary and secondary periods—the so-called 
lignite or brown coal. It is, also, nowhere found in extensive and 
vast deposits, rarely easy to work ; although that of the secondary 
division, as approaching nearer in age to genuine stone-coal, pos- 
sesses in a considerable degree the elements of fuel. In many 
