History of Texas, together with a biographical history of Milam, Williamson, Bastrop, Travis, Lee and Burleson counties : containing a concise history of the state, with portraits and biographies of prominent citizens of the above named counties, and personal histories of many of the early settlers and leading families

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legion. its height above the country on
elher side is variable. On its eastern border,
from Red river to the Brazos, there is not
that abruptness of separation which distinguishes
it at other places from the upper
and lower formations. In the northern portion
this plateau begins with an elevation of
from 600 to 1,200 feet above sea level. West
of the Colorado its northern edge reaches a
height of 2,300 feet in the ridge which forms
the divide between the water flowing into the
Colorado and that flowing south. The southern
border is, however, hardly ever more than
700 feet in height, and usually not so high.
The western and northern edge of the Grand
prairie is, generally speaking, topographically
higher than the eastern and southern, and the
dip of the beds is very gentle toward the
southeast.
The break between the Grand prairie and
the Central Basin region is equally as decided
as that between the undulating country and
i "Balcones' country " on the south, and were
it not for its intimate relations, geologically,
with the "Coastal Slope," the topographic
features of the Grand prairie would entitle it
to be considered a division by itself.
Both topographically and geologically this
area presents a gradual fall from the interior
toward the gulf coast, but the average slope
of the surface toward the southeast is less
than the dip of the strata in the same direction,
and as there has been no disturbancesof
sufficient magnitude to complicate the geology
except the uplift which brought up the Balcones
(and that of Pilot Knob and similar
areas if it be later, as it possibly is), we find
the outcropping edges of the beds of earlier and
earlier age as we pass from the coast to the
interior. These various beds are exposed in
bands of less or greater width, which are, in a
general way,parallel with the present gulf coast.

The coast clays, which are the most recent
of these, and which form a part of the present
floor of the gulf, are very impervious,
variously colored, calcareous clays, which
often form bluffs along the bay shores and
river banks. The level belt of this formation
varies from 50 to 100 miles in width.
The Orange sands underlying these are
mottled red and white sands which are well
exposed below Willis, on the International &
Great Northern Railroad, and at other places.
The Fayette beds, which underlie these, are
made up also of sands and clays, but of
entirely different character and structure.
The sand greatly predominates, especially in
the center, where great beds of sand and
sandstone and millstone grit occur.
The clays, instead of being massive, are
usually thinly laminated and of very light
color wherever exposed to the air, and are
found both underlying and overlying the
sands, as well as interbedded with them.
They extend along the line of the Houston
& Texas Central Railway from Waller to
near Giddings. A study of these beds in
the vicinity of Led better showed nearly 400
feet of sandy strata included between the two
series of clays.
The dip of the strata toward the gulf is
not much greater than that of the surface of
the country. For this'reason the exposure
of the sand-bed on the surface is very widea
circumstance of greatest importance, as it
gives an immense catchment area for the
rain-water.
These Fayette sands form a range of hills
and give rise to the most striking topographic
feature of the coast region. Every
river in its passage to the gulf pays tribute
to and is deflected by them. Many smaller
streams have their course entirely determined
by them, while the coast rivers, of which the

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Lewis Publishing Company, publisher. History of Texas, together with a biographical history of Milam, Williamson, Bastrop, Travis, Lee and Burleson counties : containing a concise history of the state, with portraits and biographies of prominent citizens of the above named counties, and personal histories of many of the early settlers and leading families. Chicago. The Portal to Texas History. http://texashistory.unt.edu/ark:/67531/metapth29785/. Accessed October 26, 2014.