iio< The American Geologist. Augrust, i904. 
At Clayton. St. Louis county, the sandstone is reached in a 
well at 1 145 feet and at Houseman's, near Brentwood, at a lit- 
tle over a 1000 feet depth. Several years ago it was reported 
that just after a sudden rise in the Missouri water in the 
Houseman well rose to the surface. Hearing of this, a project 
was conceived by certain parties' to build a dam on the ^lissouri 
where the sandstone is at the water's edge, which was a little 
more than 20 miles distant. The idea was that the water be- 
ing dammed up around the sandstone it would thoroughly sat- 
urate it and the pressure would force it along the strata to 
near St. Louis, where it could be utilized. Testing a piece of 
the Klondike rock I found that after remaining in water five 
days the weight of the rock would be increased about 5 per 
cent. But the truth remains that within 50 miles of St. Louis 
there is an inexhaustible supply of the very best sand for 
making glass, clean, pure, easy to crush and showing over 
99 per cent of pure silica. 
A REJOINDER TO DR. DALL'S CRITICISM ON DR. 
SPENCER'S HYPOTHESIS CONCERNING THE 
LATE UNION OF CUBA WITH FLORIDA.* 
Bj- J. W. Spencer, Washington, D. C. 
I have contoured the continental shelf of the Floridian re- 
gion, with lines from 200 to 500 feet apart, f Thus it has been 
found the Bahamas and Cuba are on the continuation of the same 
continental shelf with Florida. I have studied the valleys in- 
denting this shelf, their sizes and gradients as well as their 
neighboring geological formations. I have seen in these sub- 
marine valleys and their tributaries such a close analogy to the 
barrancas aiid canyons incising elevated plateaus and descend- 
ing from them to lower plains, that I have been forced to con- 
clude that they were sculptured by atmospheric agents, and 
this being the case, they became evidence that the continent 
stood at a startling elevation in late geological times. 
* "Tertiary Fauna of Florida" by W. H. Dall, Wagaer Free Inst. Sc. Ill, 
1904, p. 1544. 
i "Reconstruction of the Antillean Continent" by J. W. Spknckk, Bull. 
Geol. Soc. Am., vol. vi, pp. 103-140, Jan., 1895. Also other papers On the 
maps, the close contours have not been reproduced, to avoid confusion of 
the small scale. 
