Fort Worth daily gazette. (Fort Worth, Tex.) 1882-1891, 1890-08-03

the area pointed out TO be converted into grand
agricultural region, sure enough. 1t covers our
very best agricultural lands, which have here
tofore been held back from fullest development
on account of imperfect water supply, only
But there is one thing in your article that 90
not clearly understand, though uouptLesS you
explain it all easily enough You speak OF TINS
remarkable artesian area as lying above a great
underground river. If tins be 50, whence comes
the water Of that river, and why does IL not at
some point find its way to the surface and there
cease to be underground river why should
Texas have great rivers underground and but
comparatively insignificant rivers on the sur
face? THINKER.
Fort Worth, Tex.
The foregoing was evidently intended
for our ''enswer to correspondents
column, bnt feeling q desire TO answer it
at greater length than space in that de-
partment would consistently permit, we
have concluded TO give it a hearing here.
What we figuratively called an under
ground river is, OF course, no river at
all. Professor Robert T. Hill says it Is
more like great saturated sponge; or
rather a series of great saturated
sponges. These "spOnges" (the water
bearing stratR) are composed of coarse
sand and pebbles lying between
strata of stone lmpervious to
water In a word, there is a deposit of
sand and pebbles, which, for conven-
fence, we may term the lower water
bear ng stratum. 1t is continuous from
the head of the artesIan area described
last week, to where Texas loses interest
in the area by Its passage from her terri
tory at the Mexican line. Above this
stratum lies a thick stratum of stone that
water cannot pass through. Next, top
of this, comes another water bearing
stratum of sand and pebbles, then an
other stratum of stone, and so on, until
E,rTWN .aEr tn
lately worked out by Professor Hill, are
made up.
And now for where the water comes
from: These strata dip or incline gently
towards the gulf of Mexico; that is, they
dip little east of south. This inclined
position naturally brings the strata to
the surface at some point to the north
west, and where this occurs the waters
falling upon the country in rains pass
into the sandy or porous strata and per-
colate down between the strata of i'm
pervious stone, which last confines them
TO the porous strata and prevents their
escape to the surface. The porous strata
are kept entirely saturated or full OF
water up TO the point at which their sup
plies are received, and since this point
lies at an altitude considerably above the
common level of what we term the arte-
sian area the waters under this area are
subjected to no small degree of pressure
on account of their elevated head. AS
consequence, when we put down a bore
TO these confined waters they rush to the
surface with an amount OF force depend
ent upon the height of water-head pecul-
lar to the water bearing stratum tapped.
But where does the water get into the
water bearing strata? We have ap-
proached Professor Hill with reference
TO this matter, eliciting the fact that tor
at least the upper portion of the Fort
Worth Waco artesian area the water
bearing strata come to the surface, re-
ceiving their waters, of course, in the
counties of Wise, Jack, Parker, PalO
Pinto, Erath, COmRnche, Brown, Mills,
Lampasas, san Saba, Burnet and Llano.
A glance at any good map of Texas will
show you that no streams of any particu-
lar Importance rise in either of these
counties, hence but for what biologists
are of late making plain, we might be at
loss TO understand what disposition is
made of the watershed in this region,
but we now know that the waters enter
the porous strata coming to the surface
here, ami thence pass beneath the i'm
portant artesian area being considered,
ms the Hgre8t underground river' men,
For the benefit of such OF our young
people as have not enjoyed an oppor-
tunity of studying geology, and who may
be interesting themselves in this matter
soon, doubtless TO cut such an important
figure in Texas agriculture, we would
suggest a simple method for illustration
which they cannot help understanding.
Get q section of ordinary jelly cake and
place it on slight incline towards the
southeast. The layers of jelly between
the layers of cake will pretty we'll repre-
sent the water bearing strata-the LAYERS
of cake will represent the intervening
strata of impervious rock. Now, trim
the upper end of the cake to q level, as
the section lies, and that end will show
the region covered by the counties just
named, with the water-bearing strata
coming to the surface in proper position
TO receive the waters falling in rains. At
any point down the inclined surface of
the cake, where the surface of the coun-
try is lower than that represented by the
upper end, bore put down to either of
the water-bearIng strata will secure an
outflow of water; or, in other words, an
artesian well.
The quantity OF water flowing under,
or lying under the Fort Worth Waco ar
tesian area is simply immense. 1t is the
main drainage of an eNpRnse of country
extending westward from the counties
named as covering the inlet, no telling
how tar. If this water could be suddenly
placed upon the surface it would make
river larger than all the rivers in Texas
at medium stage, could they be thrown
into one.
At first thought this statement may
appear little surprising but such should |
not be the case. Considering their length |
and the quantity of water that falls upon
the surface in the regions through which |
they flow, our Texas rivers are entirely |
too small compared to the rivers of most |
other sections of our common country. |
This is due TO one positive cause, and, it |
may be, TO possible cause. Texas Is |
largely a country of open plains, and |
also country of, in certain seasons, q |
dry and highly absorbent atmosphere, |
therefore the waters of her rivers are |
rapidly reduced in volume by evapora-
ton. As rule, the further they run in |
dry seasons the smaller they get For
instance, the Brazos at its nearest point
TO Fort Worth is quite considerable
stream the year round, while we have
walked across it on stepping stones 200
miles below, and the citizens of that re-
gion told US they had often known it to
entirely stop running there. Evspors-
tion then is the positive cause figuring in