Evening star., 1912-11-21
THE SMOKE NUISANCE.
IV-Effect on Health and Vegetation.
By Frederic J. Haskin.

II
The harmful effects of smoke on health.
vegetation and weather are abundantiy
proyed by experience both in America and
Europe. When the great pennsylvania
anthracite coal strike was on. and many
parts of the country were forced TO SUD-
stitute soft for hard coal, cases of sus-
pected lung disease increased with the
use of bituminous coal. and after the set
1lement of the strike and the return to
anthracite they decreased again in pro-
portion to the change from bituminous TO
hard coal Cities where soft coal is burned
in large quantities. on both sides OF the
Atlantic bear witness to the harmful
effects of smoke upon health by showing
abnormal death rates from lung and
bronchial diseases. So often impermeable
to the health-giving ultraviolet rays of
light which are natures most efhclent
sermicide. the smoke pals not only de-
stroy health by filing the lungs with
SCOT. but by allowing myriads of germs to
flourish where they might be killed couid
the sunbeams reach the earth.
x
that the germ of tuberculosis dies much
more ii ii k y
Effect of Sun on W h en- h sun
gets a fair chance
Tubercular Germs. a. !, than when
1t is held in check by smoke. London au-
thorities attribute much of the famous
London fogs to the heavy clouds of black
smoke that hang over the city. and 1t
hat hon
great fogs come the death rate goes up.
During one famous fog more than a,"o
people were added To the usual death
list in three weeks. and it was estimated
that there were 10000 new cases of sick
ness. A test was made by the Engllsh
meteorological bureau with series or
burning glasses, and it was found that
nearly seven-eighths of the suns power
was shut out in the manufa ctursng dis
trict. and fve-eighths in Westminster:
The average distance that objects couid
be seen from the summit of st. Paul
or Westminster Palace tower during the.
winter months was reported by the same
bureau to be less than half mile. 1T
was also demonstrated that tuhercular
disease increased heavily with the rise
of Manchester as a manufacturing city
The method by which smoke causes fog
is an interesting natural phenomenon
The nucleus of every tiny droplet OF
water is, of course. tiny spech of dust
This little droplet in a smoky region,
foating along on the atmosphere, gradu-
ally becomes coated with a minute film
of sooty tar. This coating serves to re-
tard evaporation, and hence causes the
fog to last much longer than 1t would
if it We're simply a fog made up of un-
coated particles of moisture. Because
the heavy clouds of smoke above the
fog hold back the rays of the sun they
have much more limited power to at
tack and disperse the fog. Careful tests
have served TO give some idea of how
much the suns power of fog dispersion Is
weakened by the presence of smoke
pail. \ test was made at Leeds a lew
years ago, in which IL was demonstrated
that during calendar year the sun was
shining in the heart of the city for a
total of | .161 hours. Four miles away, at
Adel, another sunshine recorder was reg
istering the hours of sunshine, and they
totaled ,io2. In other words downtown
in Leeds there was IL per cent less sun
shine than only four miles away.
The presence of smoke in large guam
titles has been shown to kill vegetation
almost as COM
Presence of Smoke pletely as the
Bad for Vegetation. from % ; smeIter
In smaller quantities it has a retarding
effect upon plant development. 1t gets in
its deadly work in three different ways
In the first place, the SCOT gets into the
pores OF the plant and stops them up like
a coat of shellac would stop the pores
of the human body. The SCOT carries with
1t deposit of tar that will not let go
its hold on the leaves and stems or
plants even in a drenching rain. and il
the majority of plants pores were not
on the under side of the leaves it would
have small chance of surviving the at
tack of SCOT and tar.
This coating serves to obstruct many
OF the rays of sunlight that come to
plant and also to check the assimilation
Of carbon dioXide. The plant is thus
forced actually TO live in sort of twi-
light. In the third place. SCOT affects the
growth of plants through the acid it con-
tains. This acid not only exercises det-
rimental influence upon the plant through
its leaves. but also through the reduced
fermentation of the soil .humuS, and at
the same time by reducing the activities
OF the nitrifying and nitrogen-fxing or
ganisms of the plant. In other words. 1t
cuts down the food supply of the plant
and at the same time it's ability to util-
iZe it.
Extensive experiments by the Univer-
sity of Leeds show how harmful smoke
is TO plants. At one place the solids de-
acre. and the weight of lettuce a small
plate amounted to 40 grams. while at
another place. with .56J pounds of SCOT
and other solids deposited per acre, the
yield of lettuce on an identical plat
amounted TO Only forty-four grams. Ex-
periments in other localities between
these two extremes demonstrated a pro-
nounced relation between smoke and crop
Yield, in every instance the crop yield
decreasing as the amount of smoke in the
air increased. AS the ground plats were
identical as to soil. time. care, and all
other conditions except the quantity Of
smoke, the experiments prove an unex-
pectedly heavy toll is levied by smoke
upon crop yields. The same results
were shown with experimental plats OF
radishes.
The area that may be affected by a
Citys smoke is large 1t has been shown
that SCOT is fire.
Smoke Deposits quently deposited
unoD leaves sixty