Staunton spectator and vindicator. [volume] (Staunton, Va.) 1896-1916, 1907-07-12
Some Important Considerations on
School Construction.
(Continued from last week J

Continued from last week
ARTIFICIAL VENTILATION.-Ne Nearly
all systems of artificial ventilation de-
pend upon one of two thirgs: Q) The
rarifyinng power of heat anplied to air
in flues-the gravity syste (2) the
mechanical power applied 'ough the
medium of fans. The graN ~ system
of ventilation introduces hot air into
the room through an inlet connected
by fiues with steampipes creased so as
to form chambers in which utside air
is heated. The vitiated aiy tows out
of the room through separated ducts
or fues, the movement of the air being
dependent upon the lightn ness Of the
indoor air as compared with the out
door; hence more air is moved when
the temperature of the outside is ex
tremely low Ventilation by gravity
system Is sometimes unsatisfactory in
winter weather when the outside tenn
perature is not low and in spring and
fall weather. There are two means of
ventilation by the use of the fan, one
called the plenum or pressure system,
and the other the exhaust or il 1uced
system. BY the plenum system the
air Is forced into the building because
of the pressure exerted by a revolving
fan. By the exhaust system-the re-
verse OF the plenum systematic air is
drawn out of the building by fan
that is placed at the outlet end of ven
tilating ducts. The plenum system is
one commonly used. Sometimes a
com bination of the plenum and EXHAUST
methods is used, but, as rule, it is not
necessary to employ both systems. One
other system of heating and ventllat
ing uses steam for heating, the radia-
tors being placed in the schoolrOoms
and next to the outside walls Open
ings are cut through the walls at the
base of these radiators, permitting the
outside air to enter the room and be-
come heated by passing between and
around the various pipes of the radia-
tors. The outlets for bad air are U.s.
uaIly placed on the opposite side of the
room from the radiators. thus insuring
a fairly good circulation of air through.
out the room. The action of such a
system is seen in figure 1. Figure 2
the action of the air IN eth.
er the gravity or the plenum system.
Experiments seem to prove that the
inlet for the hot air should be eight or
nine feet above the floor, and the out
let in the floor, Or within one foot of
the floor, and both on the same side
of the room. Where 40 provisions are
made for adequate ventilation, the
windows must be used. The well
known device of placing q board be-
tween the sashes may be employed
Care should be taken lest the children
sit in dTaught or Where cold air is
pouring down upon the head and
shoulders. An efficient sy stem Of heat
ing and ventilating requires the ex-
penditure of money for Goa and gas in
order to heat the air and TO run the
machinery. No system has yet been
devised which will work automatically.
Any system, ii it is good for anything,
must be supervised by q competent
man. Brains are required as we'll as
coal for an apparatus designed for this
purpose.
REQUIREMENTS In some places the
law requires thirty cubic feet of pure
air every minute for each pupil. The
air should not enter the room at q great
er velocity than six and one half feet
per second, or about four hundred feet
per minute. The inlet for standard
schoolroom should be less th 4 four
square feet The air delivered should
not be over one hundred degrees
Fahrenheit. A temperature of from
69 to 20 degrees is considered proper for
schoOlroOm air. The apparatus nee
essary for the operation of 9 plen um
system is steam boiler to Generate
steam for the heating of the pipe coils
and the running of the fan engine, a
large revolving fan connected to a
steam engine, and heater composed
of coils of steampipes through which
the cold air is is either forced or drawn
before being delivered into the all
ducts or fues. The air before passine
through the heater should be filtered
through a cheesecloth screen. Thi
i removes the particles of dust which
would otherwise be delivered into tn
schoolroOm and inhaled by the pupils
The following rules respecting ventl
lation are of Importance: ~ N
ldraught or current should be percept
ble (2l Often the rem edY for q draugh
/ is not to close the opening, but to max
others III order TO increase the arc
through which the air enters. ~ Th
entry of air should be constant, an
mot at intervals. AZ An abundant ex
flor impure air should be provided sci
larate from the points of entrance {
fresh air. In order to maintain a gi'
en- standard of purity it is necessary
lprovide for the removal OF volume
Impure air equal to That of the pu
air which is supplied.
Why He Regretted the Sale.