The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1878-06-28
VENTILATION OF SEWERS.

THE THEORY ATTACKED BEFORE THE PoLYTEca.
MIC BRANCH or THE AMERICAN INSTITUTE.
Mr. Henry E. Knapp, q civI engineer oil this city,
VINO has been OF tho most prominent and active
opponents of Captain Eads theory OF applying jstties
TO harbor bars, last evening read paper before the
polytechnic branch OF ths American Institute, IN
which he attacked the theory OF ventiIatng sewers
and drains After speaking OF the amount OF study
that had devoted ny scientists 10 the subject OF
sewers, he said that the conclusion seemed almost
unanimous among engineers that tao poisonous and
mcphlc vApors should be allowed TO escape into the
spnere that the should be purified. 10
other words tho point is TO contamlnate tho atmos
phere If necessary, but purity the sewers, ransposs
the into the sewers, where u is not needed
and the sewers bring tue poisonous gases where
lney will act most detrimentally TO animal life. The
prevalence OF THIS theory, which Mr. Knapp declared
10 gorgeous error no attributed 10 the Writings
OF Robert Rawnngsou, X. q. b., personal friend
OF the Prince oiwales, who, alter tho illness OF tho
latter by typhoid lever, devoted much attention 10 the
subject spread mis- views ny means o. the pross
The first objection SIR Knapp urged against the theory
vas that the liberated gases are heavier than atmos
pheric air If liberated IRON the sewers would hug
the the earth like log, SO tnat invgoratng
air be had INSIDE the CITY. II would be al
sensible 20 ysniliate graves The sewers, Ike corpses
are buried mainly because the earth IL The best
al oi Inc products Of the decay OF animal AND
vegetable substances
BETTER WAY.
rho proper way to zeal Win sewers, he commended,
was give Them plenty OF water, winch carries sthe
matter contained ~ them TO the sea- mpedes decom-
position long as the sod matter is sufficiently
sed and powerful absorbent Of sewer gases,
especially the anmonacal, which 1t takes up To The
extent oi ABOUT oue-third It's weight or some four
hunurcd times ITS own bulk. II this be done. and
proper aps constructed evil results Will follow.
10 The scanty supply Of waste water IN Washington
attributed malaria anu mucn OF the peculiar and
uuw,se legislation Of that locality. "Our Board VI
healtn,' be continued "has committed great error
in compelling the ventilation OF sewer pipes sinks and
spvus oil ail SORTS Iho POISONOUS gases that are
emitted through them NY reason only Of the heat Of
decomposition, temporarily making the gases lighter
tnun atmospheric air drop 10 the ground Immediately
ny reduced 70 ,pncric temperature and
make u? large part u The air ". are compelled 10
breathe" supIureted hydrogen, which Is one OF the
greatest ana msst deadly products OF decomposins
sewerage, Is heavy maj II Can De poured rom QUO
uol,ie % another. Caroonic acd. another proauct
oDtai.ed W AR. Lautn from an analy sis OF PArm
sewerage US iolows:-
lev days ana alter ten g twenty asy WIS
water disclosed movable ana immo, aoie bacteria and
som d the ve.ssl Of eli kinds,
wltnou. IT CO Of living psnss After two d.y. there
Tue monsa HAD increased very mach ana koopods began
appeared ana large rnssd also agae
@ ss be 10 AK 81. ~ su ssa Sia
covered thick OF iuusorix aud
or i've weeks ns odor was stnking every Of
life lad disappeared In sewerage that has had r clown
lite active the aigae and inusoria develop
In numbers.
TRAP SUFFICIENT.
1t being maintained NY many scientists that bacteria
and inlusoria are the direct means OF CON-
munioating Contiguous diseases, Mr. Knapp claimed
ventilation vi sewers IS thereby suOwn TO be in
furious He further CLAIMED that II was needless as,
the traps III common use ~ sewer pipes we're made
with sufficient altitude, the water they would hold
would afford perfect seal and prevent the escape OF
the gases TINS altitude should not be less than SIX
times the diameter OF the pipe OF which II Is made,
but twelve times the diameter would be bettor.
trap with twelve incnes altitude would require gas
pressure nj hall pound TO force itse through tho
trap and sucn pressure could ever accummuiato In
q sewer furnished win manholes for cleaning out