Year: 1874

Catching cold is ''as easy as lying"
but to explain the pathology thereof Is
by no means so readily done. In fact,
until the recent researches Of DR..
ROsenthal, whose work on the subject
is attracting much notice IN Europe,
almost nothing was known about 1t ex-
cept the mer= fact that the ailments
popularly ascribed to "cold' are liable
to occur after the body, or some part
of it, has been suddenly chilled-that
is, cooled below the normal tempera-
ture. There are two factors concerned
in this chilling process; the nature Of
the external medium-such as alr or
water-in contact with the body; and
the condition of the blood vessels.


Dry air has very little power to ap-
stract heat, if it be still; but a slight
wind from the constant contact Of
fresh particles of cold air on the sur
face Of the body, soon carries Of its
heat. IF there Is much moisture IN the
air it greatly increases its power OF alb
stracting heat, and when wind and
moisture are combined, the chilling ef-
feet reaches its maximum. Experience
has shown that it Is not so much the ab-
solute lowness of ofthetemperature which
gives rise to colds, as sudden changes
from a higher to a lower. The
reason of this was not understood until
DR.. Rosenthal explained 1t. When the
surface of healthy animal Is exposed
to cold the eutaneOus vessels contract,
and by thus confning the blood to the
interior of the body, prevent Its cool,
ing, and preserve the temperature OF
the vital organs unless the application
of cold be continued for con-
siderable time. This is not the case,
however, when the animal has been
previously exposed to warmth. The
cutaneous vessels become paralyZed by
the heat, and remain dilated even after
the cold has been applied. The blood
is thus exposed over large surface,
and becomes rapidly cooled even
though the temperature OF the SUI
rounding medium is not very low. In
Rosenthal's experiments, animals were
kept at a temperature from about 81
deg. F. The temperature of the an
imals themselves quickly rose during
their confinement to Ill deg. or ll3
deg. After their removal it not only
sank to the normal temperature, but
even below, so that an animal which
was from Il0 deg. to Ill deg. in the
warming apparatus, fell to 96.8 deg.
and remained at that for several days,
although the room in which 1t was
kept was moderately warm. Contine-
ment in a close Office, hot theatre, or
crowded ballroom. viii have similar
effect on man. From such places, peo-
ple pass out into the cool, open ar, or
sometimes evenpurposely statiOnt them
selves in a dranght. The blood, which
is coursing through the dilated vessels
of every part of the surface. is rapidly
cooled, and, ON its return to the inter
nal organs, eools them much more
Quickly than it could have done had
the person simply been exposed to cold
without dilatiOn of the vessels by pre-
yious warmth. Rosenthal lays much
stress on the great OBJECT OF sudden
cooling in bringing on a cold, the sud
den change In the temperature OF the
blood producing an irritating effect
and inducing inhammationin in any weak
organ in a way that a gradual altera'
ton would not do. 1t would seem


however, that the alteration must bt
from a temperature above to one be-


low the normal temperature OF th'


blood, and not a mere reduction iron
one considerably above the normal u