FRESH AIR, 7 
impure by the constant and unseen action of these dead and 
living particles of matter. 
“ But we know all this ! ” I hear my sensible friends 
exclaim. Then why do you not act on it ? I am writing this 
by the sea-side, and my house is one of a row that looks on to 
the sea. Begularly as the sun sets, my friends all retire to 
their houses, the last of the chicks is put to bed, and then all 
the windows and doors are duly closed. Last night the tem- 
perature was about 65° Fah. ; a gentle south-west wind was 
blowing from the sea — to be sure, it made the candles flicker, 
but it was delicious to the feelings. I passed along the row 
of houses : it was truly a melancholy sight. Not a door, not 
a window, was open ! Now, houses at the sea-side are not 
built very durably, and a sea breeze will, no doubt, penetrate 
the rooms, lock and bolt them as you will. Nevertheless, 
there is not enough air penetrating these little rooms to take 
away the close smell of food, and dress, and human exhalation, 
and, above all, the gases which rush into the warmed house 
from every drain and dustheap about the premises. To be 
sure, the children in these houses are looking well, and the 
doctor is not often down from the neighbouring village ; but 
this I know, my neighbours^ children are not so well as they 
might be. But “ Doctor, do you not think the night air is 
injurious ? ” “No, madam, I do not ; and if it were, I do not 
see how your candles and closed rooms are to improve it.-” 
“Yes,” said a lady to me, a short time ago, “fresh air is so 
important for poor people ; but we who live in large rooms do 
not require that amount of ventilation ! ” It was evident she 
thought what she said ; for on examining the sashes of the 
windows of her splendid house, not one of them came down 
from the top. Impure air is, no doubt, a worse thing for the 
poor than the rich; for the ignorant, perhaps, than for the 
learned : but it is a bad thing for all. It is no comfort, when 
you are half-suffocated in Burlington House, at a soiree of the 
Boyal Society, to know that the most learned and scientific, 
men in Europe are suffering at the same time with yourself. 
What every sanitary reformer must feel of the utmost im- 
portance is, that sensible people, who talk about fresh air for 
the poor, should set a good example, and value it for them- 
selves. 
Let us, then, go over the foundations of our belief in fresh 
air, so as to be able to understand thoroughly the dangers 
arising out of its impurity. The pure air of the atmosphere 
contains four constituents, two of which are constant and two 
are variable. The two constant constituents are oxygen and 
nitrogen gases. They are in the proportion of twenty-one of the 
former to seventy- nine of the latter, The nitrogen is passive, 
