m giving to the caves such careful study and full reports as
they deserve, as it would have been a pleasure to give, and as has been
possible in states of less extent where the general work of the
department is more advanced, and the volume of tourist travel created an
early demand for scientific explanation.

Without any great difficulty we can understand the process of cave
excavation by the action of percolating acidulated water on the
limestone, and its subsequent removal as the volume of surface drainage
diverted to the new channel gradually increased. But it is not so easy
to offer a reason for the varied forms with which the caves are
afterwards decorated. Why is it the charmed waters do not leave the
evidence of their slow passage only in plain surfaces of varying widths,
and the stalactites and stalagmites whose formation we can readily
account for? And why do not the deposits take the same forms in all
caves with only such variations as would naturally result from
differences in topography? The law is written, but in unfamiliar
characters that render our reading slow and uncertain. Yet it is
conspicuously noticeable that those caves showing the most delicately
fragile and wonderfully varied forms of decoration are those traversed
by the most sweeping and changeable, or even reversible, currents of
air; which might lead to the conclusion that the moisture is sprayed or
converted into a light, misty vapor, and then deposited in exactly the
same manner as the beautiful frost-work at Niagara: the direction and
force of the current determining the location of the frail deposits.

Since the largest and most important caves occur in limestone, a little
special attention to the cause of their occurrence there may serve to
show that although speleology has only recently received its name and
been elevated to the rank of a separate and independent science, it is
one of the earth's ancient institutions.

Our geologists, who have unearthed many secrets not dreamed of even in
Humboldt's "good phylosopy," have settled the question of how the
different kinds of caves were formed, according to the character of
rocks they are in, or their location and depth, and the natural agencies
to whose action they show signs of having been subjected.

Dr. H.C. Hovey, in his "Celebrated American Caverns," says: "In visiting
caves of large extent, one is at first inclined to regard the long
halls, huge rifts, deep pits and lofty domes,