, fiir VIEWS OP LOUISIANA. 
are so distant from each other, that there is scarcely any probav 
bility of any being formed for centuries, if ever. 
A great proportion of the country watered by the Missouri 
and its tributary streams, appears to have undergone some won¬ 
derful change, from causes not easy to ascertain; the influence 
of fire, is however evident. I have seen in many places banks of 
clay burnt almost to the consistence of brick ; of this kind, there 
is above the Poncas village, what is called the tower, a steep 
hill one hundred and fifty feet in height, and four or five hun¬ 
dred in circumference: it is so hard, as not to be affected by the 
washing of the rains. Large masses of pumice are seen near 
these places, and frequently in the high bluffs of the river banks. 
These appearances were formerly attributed to the existence 
of volcanoes on the Missouri, but they are now generally sup¬ 
posed to be the effects of coal-banks continuing a long time on 
fire. I am well satisfied that this fossil abounds in every part of 
the great valley of the Mississippi. Many of the river hills pre-, 
sent the appearance of heaps of clay, great quantities of which, 
on the melting of the snows, and in heavy rains, are precipitated 
and carried to the principal river. This clay, is of a grey color 
extremely tenacious, being mixed with a large proportion of cal- 
earious earth: the incumbent soil havingbeen first carried away; 
the rock on which it reposed being laid bare to the frost and 
sun, and perhaps affected by the burning of coal-banks near it, 
gradually crumbled and united with the clay. In taking up a 
handful, one may pick out pieces of gypsum, (sulphat of lime) 
some of half an ounce weight. Near these spots are usually 
found glaubers salt, (sulphat of soda) and common salt, oozing 
with water out of the ground, and crystallized on the surface. 
The most remarkable fact, is the appearance on these heaps of 
clay, of the remains of trees, in a state of petrifaction and some 
of enormous size. Fragments may be every where picked up, 
but stumps of four or five feet in height, perfectly turned to 
stone, and the trunks of tall trees, may be seen and traced. This 
is extraordinary in a country, where even in the richest alluvions, 
the timber attars but a stinted growth. 
From these facts an ingenious theorist might conjecture, that 
the Missouri has not always brought down in its channel, tliat 
