MAMMOTH CAVE.



most delicate tests. Not a trace of ozone can be
detected by the most sensitive reagents.
  From what has been stated, it will be observed
that the atmosphere of the Mammoth Cave is freer
from those substances which are calculated to exert
a depressing and septic influence on the animal
economy than that of any other locality of the globe.
This great difference is observed by every one on
leaving the Cave, after having remained in it for a
number of hours. In such instances, the impurity
of the external air is almost insufferably offensive to
the sense of smell, and the romance of a "pure coun-
trY ail," is forever dissipated.
  What diseases would be benefitted, or rendered
worse, by resorting to the Mammoth Cave
  Consumptives, at one time, resorted to the Cave,
and, as might have been anticipated, with fatal
results. Several of them died there, and all of them
soon alter exposure to the external air. One patient
did not see the light of the sun for a period of five
months. Short trips are attended with advantage,
but a Cave-residence is speedily fatal.
  I know of no inflammatory disease that is rendered.
worse by a resort to the Mammoth Cave. On the
contrary, short and easy trips have been known to
effect a cure in chronic dysentery and diarrhea, where
all other measures have failed.
  In all those diseases where absolute silence, and
the total exclusion of light are indicated, the Cave,
above all other places, possesses pre-eminent advan-
tages; for nowhere else have we these conditions
combined. The only condition in which risk is
incurred is during the menstrual period. Serious,
and even fatal results, have been the consequence of
inattention to this fact.
  The temperature of the Mammoth Cave is uni-
formly fifty-nine degrees, winter and summer, which,
in connection with -the remarkable purity of its at-



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