re to cold. The capillaries of the lungs
have become engorged, and the circulation static, so that there must
be reaction of heat, inflammation, before recovery can occur. Nearly
all bronchial affections are induced in this manner, not always nor
necessarily in the acute form, but more frequently by slow degrees, by
repetition and repetition of the evil. Colds are often taken in this
same way, from the exposed mucous surfaces of the nose and throat
being subjected first to a chill, then to heat.

The wave of low temperature affecting a mixed population finds
inevitably a certain number of persons of all ages and conditions on
whom to exert its power. It catches them too often when they least
expect it. An aged man, with sluggish heart, goes to bed and reclines
to sleep in a temperature, say, of 50 deg. or 55 deg.. In his sleep, were it
quite uninfluenced from without, his heart and his breathing would
naturally decline. Gradually, as the night advances, the low wave of
heat steals over the sleeper, and the air he was breathing at 55 deg.
falls and falls to 40 deg., or it may be to 35 deg. or 30 deg.. What may naturally
follow less than a deeper sleep? Is it not natural that the sleep so
profound shall stop the laboring heart? Certainly. The great narcotic
never travels without fastening on some victims in this wise, removing
them, imperceptibly to themselves, into sleep ending in absolute
death.

SOME SIMPLE RULES.

The study of the physiological influence of the wave of low
temperature, and of its relation to the wave of mortality, suggests a
few rules, simple, and easily remembered.

1. Clothing is the first thing to attend to. To have the body, during
variable weather, such as now obtains, well enveloped from head to
foot in non-conducting substance is essential. Who neglects this
precaution is guilty of a grievous error, and who helps the poor to
clothe effectively does more for them than can readily be conceived
without careful attention to the subject we have discussed.

2. In sitting-rooms and in bedrooms it is equally essential to
maintain an equable temperature; a fire in a bedroom is of first value
at this season. The fire sustains the external warmth, encourages
ventilation, and gives health not less than comfort.

3. In going from a warm into a cold atmosphere, in breasting the wave
of low temperature, no one can harm by starting forth thoroughly warm.
But in returning from the cold into the warm th