air were more exhilarated by it than others. Upon superficial
reflection one might have supposed that this discrepancy in
physiological effect was to be accounted for merely on the basis of
constitutional idiosyncrasy; maturer thought, however, convinced me
that the exaggerated effects of the condensed air were both too
numerous and too constant to be amenable to such an explanation. This
led me to study the habits of the men; and thus it was that I arrived
at a discovery of real practical value to neurotherapy. To be brief, I
found that a certain percentage of the men, before entering the
compressed air employed in the construction of the Hudson River
tunnel, were in the habit of drinking a quantity of alcohol, usually
in the form of whisky. So long as these men remained outside the
tunnel, where the atmospheric conditions were normal, they were not
visibly affected by their potations. When, however, they entered the
compressed air of the tunnel, but a short time elapsed before they
became exhilarated to an inordinate degree, acting, as one of the
foremen graphically expressed it, "as though they owned the town."

On the other hand, when the customary draught of alcohol was withheld
from them, these same men were no more, if as much, exhilarated on
entering the compressed air as were their fellows.

The effects of alcohol, then, are enhanced by exposing the subject to
the influence of an atmosphere condensed to a considerable degree
beyond that of the normal atmosphere.

Acting on the hint derived from this discovery, I proceeded to
administer absinthe, ether, the wine of coca, vermouth, champagne, and
other stimulants, before exposing the subject to the influence of the
condensed atmosphere, and invariably observed analogous effects, i.e.,
palpable augmentation of the physiological effects of the remedy.

Upon what principle does this augmentation of physiological effect
depend? how is it to be accounted for?

In my opinion, the answer to this question may be given as follows: In
the first place, we know that the primary effect of the compressed air
upon the organism must be to force the blood from the surface of the
body toward the interior, and especially into the cerebro-spinal
canal. Or, to express it more succinctly, the blood will be forced in
the direction of the least resistance, that is, into the soft organs
inclosed by bony walls, which latter completely shut out the element
of counter-pressure. Now, w