room, school-house, and work-shop,
should be well ventilated. The blood of the system will be purer, and
its color of a brighter scarlet, if the skin is surrounded by fresh
and pure air, than when it is foul or moist.

707. The LIGHT permeating the skin, not only exercises a salutary
influence upon this membrane, but upon the blood, and, through this
fluid, upon the whole system. For this reason, the kitchen and the
sitting-room, which are the apartments most used by ladies, should be
selected from the most pleasant and well-lighted rooms in the house.
On the other hand, dark rooms and damp cellar-kitchens should be
avoided, as exercising an injurious influence upon both body and
mind.

708. The dark, damp rooms, so much used in cities and large
villages, by indigent families and domestics, are fruitful causes
of disease, as well as of vice, poverty, and suffering. Common
observation shows that solar light also exercises much influence
upon the vigor and color of vegetables. Plants that are kept in
well-lighted rooms, have darker and more brilliant colors than
those that grow in darkened apartments.

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705. Give the reasons why pure air should be supplied to the skin.
706. What is the cause of the general lassitude in a damp, warm
morning? 707. Show the salutary effects of light on the skin. 708.
What is one cause of disease and suffering in large villages?

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709. BURNS and SCALDS are terms applied to those conditions of the
skin which are produced by the application of an undue amount of heat,
which changes the action of its vessels.

710. A small degree of heat will irritate the nerves, and cause an
increased action of the blood-vessels. This is attended with severe
smarting pain, and will be followed by the deposition of serum under
the cuticle, unless applications are made immediately, to prevent
vesication, or blistering. To prevent or suppress this state of
arterial action, wet some folds of cotton or woollen cloth with cold
water, and apply them to the parts scalded; continue to apply cold
water, so as to steadily maintain the low temperature of the
applications, as long as the _smarting pain_ is experienced. The
steady application of cold dressing also tends to prevent an increased
action of the blood-vessels, and will suppress it, if it already
exist.

711. When blisters are formed, the cuticle is separated from the other
tissues of the skin by th