We will now cross the Alleghanies westward, where we shall find a
thickly-wooded country. As we proceed onwards, entering Kentucky, we
reach a spot of great geological interest, called the Big-bone Lick.
These licks exist in various parts of the country. They are marshy
swamps in which saline springs break out, and are frequented by buffalo,
deer, and other wild animals, for the sake of the salt with which in the
summer they are incrusted, and which in winter is dissolved in the mud.
Wild beasts, as well as cattle, greedily devour this incrustation, and
will burrow into the clay impregnated with salt in order to lick the
mud. In the Big-Bone Lick of Kentucky the bones of a vast number of
mastodons and other extinct quadrupeds have been dug up.
This celebrated bog is situated in a nearly level plain, bounded by
gentle slopes, which lead up to wide-extended table-lands. In the spots
where the salt springs rise, the bog is so soft that a man may force a
pile into it many yards perpendicularly. Some of these quaking bogs are
even now more than fifteen acres in extent, but were formerly much
larger, before the surrounding forest was partially cleared away. Even
at the present day cows, horses, and other quadrupeds are occasionally
lost here, as they venture on to the treacherous ground. It may be
easily understood, therefore, how the vast mastodons, elephants, and
other huge animals lost their lives. In their eagerness to drink the
saline waters, or lick the salt, those in front, hurrying forward, would
have been pressed upon by those behind, and thus, before they were aware
of their danger, sank helplessly into the quagmire. It is supposed that
the bones of not less than one hundred mastodons and twenty elephants
have been dug up out of the bog, besides which the bones of a stag,
extinct horse, megalonyx, and bison, have been obtained. Undoubtedly,
therefore, this plain has remained unchanged in all its principal
features since the period when these vast extinct quadrupeds inhabited
the banks of the Ohio and its tributaries. Here and there the Big-bone
Lick is covered with mud, washed over it by some unusual rising of the
Ohio River, which is known to swell sixty feet above its summer level.
Passing on through wide-spreading prairies, we cross the mighty stream
of the Mississippi to a slightly elevated district of broad savannahs,
till we reach a treeless region bordering the very foot of the Rocky
Mountains. Through this region numerous rivers pass on their way to the
Mississippi. Leaving at length the great western plain, we begin to
mount the slopes of the Rocky Mountains, when we may gaze upwards at the
lofty snow-covered peaks above our heads. Hence, crossing the mighty
range in spite of grizzly bears and wilder Indians, we descend towards
the bank of the Rio Colorado, which falls into the Gulf of California,
and thence over a mountainous region, some of whose heights, as Mount
Dana, reach an elevation of 13,000 feet, and Mount Whitney, 15,000 feet.