The Grange advance., 1874-04-15
Ventilation Of School Rooms.

senSll8t1On VI DCuOOl hOOUSs
We give below an analysis Of the re-
marks Of DR.. Hewitt, Secretary Of the
State Board Of Health, on this subject, to
the Teachers Of our Public Schools:
The State Board are making careful
study Of the ventilation Of the State Insti-
| :u;icns and Of school buildings. As part
| u that work the Doctor has examined the
Red Wing schoo; buildings. His conclu-
sions Oh the general subject are Of SO much
| Importance that they deserve larger au-
dience than that to which they were given.
He said there should be no mistake as to
what is meant by ventilation. False meth
DDS aud consequent failures have come
from wrong ideas Of what can in this way
be done.
The object Of ventilation is the removal
Of the impurities added to the fir Of inhab-
tied buildings by the resp;raI ion and cuta-
neous Transportation Of : men and by lights
and fires. It is accomplished by the pas
sage Of stream Of pure air taken from
the outside atmosphere.
1t cannot remove other Impurities which
come from unciean1ihesy rooms. furni-
ture Or persons; from solid or fluid nasti !.
ness permitted to accumulate in dirty
houses. nor can it alone remove the effluvia
from sewers, cess pools. or drains allo wed
to gain access to the interior of the houses
1t is "ever to be forgotten that with the most
perfect ventilation possible, the air Of inhabited
buildings is never 80 pure as the outside atuos-
phere.
! Ventilation is, therefore, but one method
Of cleanliness: to be successful it must be
used in common with other methods. This is
the invariabie rule Of nature. Its methods
in the house must be the least possible
modification Of natural methods, the prin-
ciples are the same The last we expound
in two natural laws, viz: I, the law of diff
fusion Of gasses. II, the law of the expan-
sion Of air by heat and its contraction by
cold.
| To illustrate the first Of these laws here
are few facts: carbonic acid gas has
specific gravity Of is, i. e. it is heavier
BY one-half than common air in which it
exists in small comparative amount. 4 parts
in 10000; greatly in excess of this amount
it is dangerous and even fatal to life.
Now every adult person adds to the air
about fourteen cubic feet Of this gas every
twenty-four hours. and the population of
our State in the same time gives to the air
6,0O0, 900 cubic feet. Their fires and lights
add probably l2.0O0,00o cubic feet more,
and domestic animals as much more, be-
side it is produced in variety of other
ways. So that at least 100000 cubic
feet Of this gas 60 into 6ur common air
from these sources alQp{, every day, and
yet its diffusion is 50 imm& &diate and perfect
that the difference in its proportion to the
other elements ef air~is pot discernible.
This diffusion of gases take qs place wherev-
er air penetrates through wood, mortar,
| brick and even stoue, and to great depths
! in the earth.
Familiar illustrations Of the operation of
the second law are found in the phenomena
Of winds and storms.
The atmosphere is never entirely at rest,
it is always in a state of unrest, 50 that by
| the operation Of these laws the composition
Of the external air is always uniform.
| The elements of the atmosphere are not
chemically combined. 1t is mixture Of
gases holding water as vapors in suspen-
sion in this way it is most properly fitted
for its work, to carry food to the myriad
forms Of organic life and material for the inf
mite variety of changes which make up the
activities Of the sinorganic world 1t is not
difficult to understand that, shut up within
the walls Of building deprived ofits oxygen
BY organic PROCESSES and mixed constantly
with the efauvi4from body and breath, from
decaying animal and vegetable matter, from
fires and lights it can become very offen-
sive, foul, and suoxious mixture, sort Of
stirabout'' Of fetid gasses, vapors and
organic particles
Inst even " our best houses it is so
made a direct cause Of disease is proven by
statistics. i
The great m&ority Of disease causes gain
entrance to our bodies through the air, in
fsnts' I. E. children under i've years Of age
furnish in their little bodies the most deli
cate tests Of tie influence Of disease. These
little children furnish more than forty per