recaution be observed to secure a pure atmosphere.

916. Warmth.

Warmth is essential to all the bodily functions.

_Therefore_, an equal bodily temperature should be maintained by
exercise, by clothing, or by fire.

917. Exercise and Clothing.

Exercise warms, invigorates and purifies the body; clothing preserves
the warmth the body generates; fire imparts warmth externally.

_Therefore_, to obtain and preserve warmth, exercise and clothing are
preferable to fire.

918. Ventilation.

Fire consumes the Oxygen of the air, and produces noxious gases.

_Therefore_, the air is less pure in the presence of candles, gas, or
coal fire, than otherwise, and the deterioration should be repaired by
increased ventilation.

[SO THE LOVELIEST WOMAN MAY LACK VIRTUE.]

919. Clean Skin.

The skin is a highly-organized membrane, full of minute pores, cells,
bloodvessels, and nerves; it imbibes moisture or throws it off,
according to the state of the atmosphere and the temperature of the
body. It also "breathes," as do the lungs (though less actively). All
the internal organs sympathize with the skin.

_Therefore,_ it should be repeatedly cleansed.

920. Over-Work.

Late hours and anxious pursuits exhaust the nervous system, and produce
disease and premature death.

_Therefore_, the hours of labour and study should be short.

921. Body and Mind.

Mental and bodily exercise are equally essential to the general health
and happiness.

_Therefore_, labour and study should succeed each other.

922. Over-Indulgence.

Man will live most healthily upon simple solids and fluids, of which a
sufficient but temperate quantity should be taken.

_Therefore_, over indulgence in strong drinks, tobacco, snuff, opium,
and all mere indulgences, should be avoided.

923. Moderate Temperature.

Sudden alternations of heat and cold are dangerous (especially to the
young and the aged).

_Therefore_, clothing, in quantity and quality, should be adapted to the
alternations of night and day, and of the seasons; and drinking cold
water when the body is hot, and hot tea and soups when cold, are
productive of many evils.

924. Summary.

Moderation in eating and drinking, short hours of labour and study,
regularity in exercise, recreation, and rest, cleanliness, equanimity
of temper and equality of temperature,--these are the great