crystalization. It is the result, I presume, of an unusual combination
of the sulphates of lime and magnesia, with a carbonate of the former.
We found here and elsewhere in the Cabinet, fine specimens of the
sulphate of Magnesia, (or Epsom salts,) a foot or two long, and three
inches in thickness.

Leaving the quiet and beautiful "Cabinet," you come suddenly upon the
"Rocky Mountains," furnishing a contrast so bold and striking, as
almost to startle you. Clambering up the rough side some thirty feet,
you pass close under the roof of the cavern you have left, and find
before you an immense transverse cave, 100 feet or more from the
ceiling to the floor, with a huge pile of rocks half filling the
hither side--they were probably dashed from the roof in the great
earthquake of 1811. Taking the left hand branch, you are soon brought
to "Croghan's Hall," which is nine miles from the mouth, and is the
farthest point explored in that direction. The "Hall" is 50 or 60 feet
in diameter, and perhaps, thirty-five feet high, of a semi-circular
form. Fronting you as you enter, are massive stalactites, ten or
fifteen feet in length, attached to the rock, like sheets of ice, and
of a brilliant color. The rock projects near the floor, and then
recedes with a regular and graceful curve, or swell, leaving a cavity
of several feet in width between it and the floor. At intervals,
around this swell, stalactites of various forms are suspended, and
behind the sheet of stalactites first described, are numerous
stalagmites, in fanciful forms. I brought one away that resembles the
horns of the deer, being nearly translucent. In the centre of this
hall, a very large stalactite hangs from the roof; and a corresponding
stalagmite rises from the floor, about three feet in height and a foot
in diameter, of an amber color, perfectly smooth and translucent, like
the other formations. On the right, is a deep pit, down which the