legislative hall, the legislature being in session. I remained half
an hour in the most impure air I ever breathed. Our school-houses are,
some of them, so vile in this respect, that I would prefer to have my
son remain in utter ignorance of books rather than to breathe, six
hours every day, such a poisonous atmosphere. Theatres and concert-rooms
are so foul that only reckless people continue to visit them. Twelve
hours in a railway-car exhausts one, not by the journeying, but because
of the devitalized air. While crossing the ocean in a Cunard steamer,
I was amazed that men who knew enough to construct such ships did not
know enough to furnish air to the passengers. The distress of
sea-sickness is greatly intensified by the sickening air of the ship.
Were carbonic acid _only black_, what a contrast there would be
between our hotels in their elaborate ornament!"

"Some time since I visited an establishment where one hundred and fifty
girls, in a single room, were engaged in needle-work. Pale-faced, and
with low vitality and feeble circulation, they were unconscious that
they were breathing air that at once produced in me dizziness and a
sense of suffocation. If I had remained a week with, them, I should,
by reduced vitality, have become unconscious of the vileness of the
air!"

There is a prevailing prejudice against _night air_ as unhealthful
to be admitted into sleeping-rooms, which is owing wholly to sheer
ignorance. In the night every body necessarily breathes night air and
no other. When admitted from without into a sleeping-room it is colder,
and therefore heavier, than the air within, so it sinks to the bottom
of the room and forces out an equal quantity of the impure air, warmed
and vitiated by passing through the lungs of inmates. Thus the question
is, Shall we shut up a chamber and breathe night air vitiated with