t supply of air. When trustees and patrons realize that pure air
is absolutely essential to health, and that their children are being
slowly poisoned by the foul air of school rooms, then they will
construct our halls of learning with a due regard for the laws of
hygiene, and students will not droop under their tasks on account of the
absence of Nature's most bountiful gift, _pure air_.

VENTILATION OF FACTORIES AND WORKSHOPS. This is a subject which demands
the immediate attention of manufacturers and employers. The odors of
oil, coal gas, and animal products, render the air foul and stagnant,
and often give rise to violent diseases among the operatives. From two
to four hundred persons are often confined in workshops six hundred feet
long, with no means of ventilation except windows _on one side only_.
The air is breathed and re-breathed, until the operatives complain of
languor and headache, which they attribute to overwork. The _real_ cause
of the headache is the inhalation of foul air at every expansion of the
lungs. If the proprietors would provide efficient means for ventilating
their workshops, the cost of construction would be repaid with compound
interest, in the better health of their operatives and the consequent
increase of labor. Our manufacturers must learn and practice the great
principle of political economy, namely, that the interests of the
laborer and employer are mutual.

VENTILATION OF OUR DWELLINGS. Not less important is the ventilation of
our dwellings; each apartment should be provided with some channel for
the escape of the noxious vapors constantly accumulating. Most of the
tenements occupied by the poor of our cities are literally dens of
poison. Their children inhale disease with their earliest breath. What
wonder that our streets are filled with squalid, wan-visaged children!
Charity, indeed, visits these miserable homes, bringing garments and
food to their half-famished inmates; but she has been slow to learn that
fresh air is just as essential to life as food or clothing. Care should
be taken by the public authorities of every city, that its tenement
houses do not degenerate into foul hovels, like those of the poor
English laborer, so graphically portrayed by Dickens. But ill-ventilated
rooms are not found exclusively in the abodes of the poor. True, in the
homes of luxury, the effect of vitiated air is modified by food, etc.
Men of wealth give far more attention to the architecture and a