Eureka daily sentinel. [volume] (Eureka, Nev.) 1871-1887, 1879-11-19
A CHAPTERsO ON VENTILATION.
suggestions from a Gentleman who
In W~eii-versed ON the Subject.

IN "eii-versed ON the Subject.
EDITOR SENTINEL In devising means for
Vennlating rooms, several problems are
presented. These are economy in the use
OF fuel, equal distribution of heat, and a
plentiful supply of pure and properly tenn
pered air.
Before entering upon a detailed examin-
atom OF the various methods of heating
and ventilation, we will discuss the neces-
sity OF ventilation, with the principles upon
which it is founded. Pure air contains 10
parts nitrogen, q parts oxygen, and .0OO5
parts carbonic acid gas, and a variable guam
tity OF water. Oxygen is the DEMONSTRATING
principle. Carbonic acid gas is chiefly
produced by combustion. When air is
confined in rooms where combustion and
breathing is going on, some means must be
devised for carrying it off, or the air is soon
rendered unfit to sustain life.
In breathing, an adult DESTROYS the vital
ity of eight cubic feet Of air every minute.
In a school room, 24x30 feet, and - feet
high. so pupils would render the $500
cubic feet of air unfit to breathe in less
than twenty minutes. In the construction
of any school house, where ventilation is
neglected, somebody is responsible for the
outrage. When windows are opened for
the admission of air, a cold current imme-
diately flows in, which settles to the bot
tom Of the room; on its way it strikes the
heads and necks of the pupils, causing
colds in the head, rheumatic pains, and
other forms of disease. And yet many peo-
pie will contend that ventilation is snfi-
GENTLY secured by the abominable practice
of opening windows from the top. Another
method of ventilation is by openings in
the ceiling. When the opening is into a
room above, no ventilation is introduced,
for no currents are created. When the
outlet is through a fiue to the open air, the
hot air at the top Of the room is drawn off,
and the equally foul air at the bottom, re-
mains. By this method there is great
waste Of heat, and but slight change of air.
With the open fireplace a current Of air
Is always setting in towards the fire, max
ing the ventilation nearly perfect. The
heat, however, is transmitted by radiation.
and hence is unevenly distributed, and the
current of air which constantly ascends
through the chimney causes a great waste
OF heat. By radiation heat passes outward
from a heated body, in all directions. The
intensity Of radiated heat is inversely as
the square of the distance travelled. Ra-
dated heat does not raise the Temperature
of the air through which it passes this is
shown by the fact that the upper atmos-
phere is much colder than the stratum of
air IN immediate contact with the earth,
whereas it would be warmer as we 90 to-
wards the sun if the air was heated by ra-
diation.
The capacity Of bodies to receive heat
greatly varies. To raise a cubic foot of
water to a given temperature requires l, 700
times the amount of heat that it does to
raise a cubic foot of air to the same tenn
perature. The capacity of air to receive
heat is relatively small, and hence, there
Is little loss OF heat from a perfect system
OF ventilation. When confined in a room
the cold air sinks to the bottom, and the
warm air rises to the top. Carbonic acid
gas is heavier than air. In a room at the
temperature Of 10 degrees the carbonic acid
Of the breath at the temperature of 80 de-
grees rises, but speedily giving off the ex-
ira heat, sinks again, and accumulates at
the floor.
The best known apparatus for heating
which has yet been invented is probably
the hot-air furnace. By its use the air Is
tempered before being admitted to the
room, and cold draughts are rendered i'm
possible. If properly adjusted, it comes
nearer to solving our problem than any
other.
Hot-air furnaces, however, are too costly
for common schools, as in outlying dis
tricts may get out Of order and cause seri-
Gus Inconvenience. A system has been de-
vised for the use OF stoves, and il properly
carried out, will have all the excellencies
OF the above apparatus. The stoves used
may be the ordinary box stoves for wood or
coal. The best known arrangement, after
a long series Of experiments. is found in
placing the stove in the corner Of the
room. The ventilating registers are to be
placed at the farthest distance from the
stove, and at the bottom Of the room. In
another corner Of the room make proyi-
zion for the admission Of cold air by means
of a flue, with a damper attachment to
regulate the supply OF cold air. This flue
should have height sufficient to furnish a
draught, thus forcing the cold air to ascend
and become tempered before 1t can reach
the floor. This latter system is the one
adopted in the new school building now
being erected In Eureka. b.
EUREKA. November II, 1879.