Evening star. [volume] (Washington, D.C.) 1854-1972, 1883-10-27
Concerning Ventilation.


Concerning Ventilation.
DR.. Charles r. Dryer, of the Fort Wayne (Ind.)
College of Medicine. in a communication to a
medical journal, speaks OF some Of the popular
fallacies in regard to ventilation as follows: The
first and great popular fallacy in regard to ven
tilatiOn is that 1t needs no special attention.
This is more serious error among the well-to-
do than among the poorer classes, inasmuch as
the houses Of the former are more nearly air.
tight. With solid brick walls, dOuble-sashed
windows, weather-stripped doors, and base
burning coal stove, the exclusion Of pure air Is
carried to the utmost extent. The condition is
happily somewhat relieved by the use Of open
coal CRATES. But how many fine houses does
the physician enter without noticing the close
foul OdOr, and the sitting air which comes from
OVer-heating and poor ventilation? In such
rooms he finds nervous. headachy women,
and pale. irritable children suffering from colds
the winter through. Such families need Judi
cious instruction that respired air contains one
of the most virulent poisons known. and that
dry and over-heated air is debilitating and irri-
tat,ng. leaving the mucous membranes sensitive
TO De lhfiamed by every breath of the natural at
mOsphere.
The second popular fallacy is that the poison
OF resp.red air is carbonic acid.
This is an example of superstition at the ssur-
vivai' In science Of an idea long after it has been
proved to be false. 1t is perpetu ated in school
hooks and popular treatises innumerable. In
Deed. correctness of statement upon the subject
| is this rare exceptions gross error the rule.
Carbonic acid gas is no more poisonous than
water; animals immersed in it die just as they
do II immersed In water, and for the same
| reason viz, want of oxygen. Birds have been
made to live in an atmosphere containing $40
per cent OF pure carbonic acid and about an
equal per cent Of oxygen. Yet when the car
bonic acid of respired air rises to one per cent
that air is very dangerous poison. The sou-
ton of this puzzle is that respired air contains
very small proportion of poisonous organic mat
ter which is constantly eXhaied from even the
heathiest lungs. Its exact nature has not been
determined. 1t is the source of the foul odor SO
characteristic of badly ventilated rooms. The air
from the exit of pipes of a crowded hail darkens
sulphuric acid declorize potassium permanga-
nate, and causes water or a sponge saturated
with it to putrefy. This poisonous matter is
produced In quantities propOrtionate to the
amount of carbOnic acid hence the quantity of
the latter is an indicator Of the relative quantity
OF the power. aud carbOnic acid should never be
allowed to accumulate in occupied rooms to the
extent OF seven-tenths of one per cent.
The third popular fallacy is that the most i'm
pure air accumuIates near the floor of the room
This false idea has probably arisen from the fact
that carboDic acid is more than half as heavy
again as air, and can be poured from one dish
into another like water Although this Is true
when both gases are at the same temperature
very little difference OF temperature is sufficient
TO reverse these conditions. ReSpired air issues
from the nOstris at a temperature of nearly 100
degrees Fahrenheit, and is lighter than the
cutter air at 70 degrees or 80 degrees. Again,
the temperature OF the body is nearly 100 de-
grees, usually much above that of the surround
Ing air. This is sufficient to create an upward
current rising from the body of every person In
the room, just as the heated air rises above
not stove. IL to these influences be added the
more powerful action of q stove, register or
other heating apparatus 1t will be understood
how the pure air rises and accumulates very
rapidly near the ceiling. This can be easily
proved by experiment. such as placing candles
at various heights. The upper one will burn
more dimly than the lower. At the same time
the cooler air from the floor moves toward the
stove to enter it, or to join the current rising
from it.
The fourth popular fallacy is that the outlet
for impure air is best placed at the top of the
room, and the inlet for pure air at the bottom.
This may seem contradiction to the third fall
lacy: but is not, for several reasons: An open
ing into cold place at the top Of the room is
often not an outlet at all, but simply allows cold
air to drop down into the room. II be an out
let it is very wasteful of heat. The air Of the
room is heated at some expense, and then turned
out of doors as soon as possible. If the inlet be
near the floor, there will be cold draught upon
the feet of the occupants Of the room, and al
though such an arrangement may ventIate, it
will be attended with such disadvantages as to
render it highly Objectionable. Wherever pos
sble, there should be an outlet near the
floor, into heated flue in which the up
ward draught is sufficient to constantly draw
the cooler air off the floor. An open fire flue is
the most efficient outlet that can be devised
Instead Of that a direct draught stove, in which
door above the fire may be opened. answers
the purpose admirably. The inlet may be for
pure-heated air through register near the floor
on the opposite side of the room from the out
let, or for pure cold air by an opening directed
upward behind the atoYe, and above the heads
of the occupants Of the room. Thus cold
draughts will be avoided. the pure cold air will
mingle Immediately with the pure air near the
ceiling, and the room will be equally and eco
nOmcally warmed and eniciently ventilated.
June air may be had in January, and the chill
dren will be as merry and rosy as the street
children, who have nothing but oxygen to make
them merry.