New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1868-07-13
SCIENCE.

VENTILATION OF PUBLIC BUTDNGs.-ln a
paper read 10y Gen NORM, Director OF the Imperial Con
bervatOry OF Arts aud Trades, before meeting Oh III
thanical engineers, IN Paris the opinion Is aI
the different arrangements for getting rid OF yta'ed ar
and replacing by iresh ar by means VI
well proportoned and well carried out are more
than those which depend exclusively on ooMs ~ ~ M
ar, as the latter DO not IN every lnstanOe anu a. an
times, insure the vated air beng uniformly ana con
19ns expelled tb Inc brt from Which It has to be-
drawn and whatever the quantity can DC OBTAINED by
ratus by giving the inlet openings for the fresh air
sufficiently large dimensions and placing them in suitable
Dosifions Suction can be easily obtained either by
Of open fire places with chimneys, or similar heating ap
partu or bv of special replaces placed at the bot
tom Of the exhausng dues, and acting auxares when
the rooms large The air 10 be removed ought 10
aow toward the bottom Of these freplaces and when
possible, by means Of special airues leading from
openings close to the sources OF ventilation. Ventilation
by suction through fire-plaees and chimneys can be
adapted TO proportions arrangements of every
kind OF IL resembles the ordinary and natural
ventilation of rooms and the volume and temperature OF
she fresh be varied required IL only neces
Bary construct at small expense frepaces with thin
ehimneys and air hues which when completed cost Dlt
little for repairs, and TO supply the repaces with fuel
which any common attendant s competent to 40 On the
contrary, ventilation Dy means OF DlOWing ana Oter me
chancd apparatus, necesstates beside the hues and
cbimneys common TO both systems the addition of blow
Dug machines and engines with special
artisans, engineers, ana hrenen, and involves an
extra cost for keeping up. Besides this system
does not afford the same guarantee as that Of
suction, against differences Of viuated air. especially IN
hospitals several stories in hight where may pass nom
into another through the openings of the dis
charging ues when 1t happens that the pressure and
ings Of doors windows There may be special cases
where it would be advantageous to use mechanical
the quantities OF air to be removed differ greatly IRON
one day and from one hour to another as IA the case OF
st. Georges Han, Liverpool, in which mechanical ventila
ton exclusively is used and the quantity OF ar required
varies IN the extreme proportion OF to go The follow
ing proportions for the quantity Of air required to be
of large number of expeTments by different observers,
and although larger than the rates formerly adopted are
not IN Cen Morin's opinion at all exaggerated;
Schools for each child, per honr...."... 4o9 to 500
Meetrg hans Tor each person per 900 to 1000
phat,rs for each person per ooqr. 70 S
W ls 5 o taSI i ItI'-' yer n bo1r 200
WorsoTp. Unhealthy 1 Sde! per hour 500
Hospitals Tor epidemic ................" 5000
The temperature of the air in places abundanty ven
tilaed, and having continual renewal OF arr can DC
maintained at higher point than in rooms not Wen ven
exceed the degrees given without fractions, on both
the Fahrenheit and Centigrade Thermometer; ~.
.o - or ,s,oS
20 63, OF 1910 20
hsseg TO TO n OF aotozs
Tie fresh air supplied should he at nearly the
Temperature as the one to be maintained IN the ROOM
but II there is large cooling surface OF glass IN WIN
dows has TO be increased 70 as high as $50 to 9 tahr
heated by large number OF artificial lights or by pres
~ large cOncOurse Of persons For the purpose or
regulating the temperature the supplied arr warmed by
some heating apparatus, has TO be received hFSt INTO
chamber into which cold air can be introduced for mix
Ing with it, 1t has been found by practice as well as by
theory, that the average velocity OF air IN the nue.
new end the square root OF the excess the temperature
of the in the ue that of the external arr having
the of the chimney IL easy to estimate the volume
The Dofion of the openings for the admission and re-
mova Of the air point of great importance None of
these should be level with the floor where they would
for the admission OF air whether cold should be
placed the ceiling, at such hight that no person
NAV receive the impression of draft Openings for the
abstraction Of air should the contrary, be placed gen
orally in the lower part of the room.
The velocity of the ytiated air. ~ its passage outward
of the building which is best effected by the use Of sim
gle shaft On its entrance the air should move about
three feet per second and at It's exit about SIX feet An
Of 10 TO 80 degrees Fahrenheit in the temperature OF
the dischargng shaft over that OF the external ar Win
produce the required increase Of speed but IN
theater where the for air must be complicated
difference OF temperature OF 20 20 100 degrees Ealhl
heit is required to effect the desired result When the
supply openings the side Of the room at consider
able hight the velocity OF the entering ar may De as hgh
one meter 33 inches per second without causing IN
that the air descend vertically its velocity should not
be more than half that just stated.
The suction system has been objected TO for causing
strong drafts when outside door Is opened but this
may be Obviated by adopting suitable proportions ana
by warming the anerOOms and passages leading out OF
the building. The cnmneys OF dwellings will generally
produce sufficient ventilation, even when there are no
Rture within and without. However, this Nentiatng
Chimney a vertical pipe containing few gas burn
In answer TO query whether It had been found es
sental TO Introduce moisture with the ar s3ppneu,
Gen. NORM remarked that IN tne plan OF hea'lng
ADOPTED WITH R the ' cod a and it Was '' found
there was moisture enough 10 prevent any sensation
OF dryness IN Ihe ar wien UIeaIHSua III 55 ~ an f
Ventang in hot countries where il would be required
supply OF fresh air, whether the points OF
admitting and dscharng air would in that case have TO
be reversed Gen NORM said the Lecture Theaer OF the
Conservative in which they then assembled, was
ventilated upon the plan described In his paper aud 1t
found in practice that the room could be cooled IN
warm weather readily by drawing OF the yltlated
air near the floor and admitting fresh air brought from
below near the ceiling. In very hot countries might De
found essential to have recourse TO fine spray OF water
lust sufficient 20 mOiSten the surface which the fresh
AIR had pass its into ROOM so as TO bring INTO
play the effect of rapid evaporation. All the detdls
OF the plans, applied in the Public School, Rue des
Pes Hotels, I'm the Theatre Lyrquc, and il the Con
eeryatOre were exhibited and explained by the speaker
The uniformity OF temperature IN tie Theatre Lyllque
was striking result. At trial in November when me
Temperature without A. C.. the 10, in
tile orchestra stalls 90 in the boxes 23 and in the gal