Every evening, Wilmington daily commercial., 1922-08-23
SCIENTISTS CALL DUST
A FACTOR IN OUR LIFE
Tiny Particles an Evil and Bene-
fit, Too, 10 Decision Of
Students.
DIR. Stephen Richnrx. in New Yor
Timer.

Ia not dust an evil and a nuisance?
Ask the servant who sweeps many
rooms, who dusts the furniture again
and again and brushes the clothes every |
day; ask her il she has blessing for this
fellow called dust; ask her
about his value.
Dust really is an evil, and danger
for the man in the factory, for the |
hewers of coal in the mines, for oil
those who have to breathe the dusty |
and unhealthy air of our cities, Many
people have weakened and spoiled their
lungs by dust and others have found
An early death because Of IT, But dust
is not only vexation. II plays an
important part in our life.
Wind sweeping dry soil, q car rolling
over the road, people walking about,
cause quantities of dust TO be whirlcd
up. The blast on the ocean takes alongs
salt dissolved in the water and carries
il high up in the atmosphere and TO
distant continents, thus augmenting the
dust. Moreover volcanoes send forth
immense streams Of dust, thrown many
miles from crater in vertical and
horizontal directions. A small percent
age of the dust. comes down from the
universe TO the earth, brought by shoot
ing stars, fragments OF other worlds,
WHICH, flying through the atmosphere,
burst into small particles. II is, how
ever, to artificial causes that most of
the dust may be traced. The burning
of coal is the principal source OF dust
in our centers OF industry.
In the dust from these many sources
we find everywhere, but mostly in the
crowded cities, tiny beings of the vege-
table kingdom called bacteria. Al
though not recognizable except by a
microscope Of high power, they are dan
gerous and the cause Of practically all
epidemic diseases Living in cities, we
cannot help but breathe them daily by
millions, and it is only healthy con-
stitution which can overwhelm these
dangerous foes.
An interesting and useful experiment
is TO count the particles of dust in dif-
| ferent places. But are they not count
| less? II we look at sunbeam floating
in our room, reflected a thousand and
a hundred thousand fold by the dancing
dust particles before hidden from our
eyes, but now in the flood of light be-
coming visible, we should certainly say
they were innumerable. But scientists
found away to count them. They col
lect the dust of known measure, foi
instance, of the tenth part of a cubic
inch, and count these prticles by means
Of miscroscope. In this way the mum
ber Of dust particles from different
places become known. They are fewest
on high mountains, only about 300 par
ticles in one-tenth of cubic inch. 1r
the open air of cities there are some
hundred thousands, and in closed room!
100000 were gathered in this SAME
small volume. A burning petroleum
lamp yields 500, 100000 dust particles
in one cubic inch; that is, in three cubic
inches almost as many as there are
people living on earth. A cigarettt
smoker at every draught throws foNl
1000, 100000 dust particles.
From all this we may estimate th'
smallness of q single particle. Scien
fists found diamcters down to 300 mil
lionths of an inch. The smallest par
ticles are OF the greatest consequence
in human life. The particles in our at
1mosphere serve as small mirrors. tn
light of the sun is reflected by then
dS GNeINDOdN lCIoldhNio WlAti l0OhiiA
at the thousands of tiny dust particle
dancing in a sunbeam, Billions an
trilions of these mirrors in the atmos
phere play the part of reflectors. Thu
!. it is possible for the sunlight to pens
trate where the sun itself cannot b
seen.
An experiment may illustrate tn
. statement. Put a glowing lump OF iro
in a shaded room. The red hot iro
will sweep away all of the dust in il
surroundings. By taking away the iro
we see a dark spot because there
nothing to reflect the light. But 500
: the darkness is again illuminated, II
dust coming back and rejecting the SUI
light again.
In a measure we observe the san
. thing every day. After sunset we hay
y twilight for an hour or so. The su
: although below the horizon, shines upc
n the upper layers of the atmosphere al
e the sunlight is reflected, but it is nc
S the air itself which reflects, being
|. gaseous matter, but the dust floating
n the air.
T What would happen if no dust were
s the air? We know heavenly body
this kind. Our steady companion /,
our journey through the universe, q
moon, has no atmosphere and thereto
no dust. Hence, as we observe with &
telescope, the mountains OF the mo-
Z, have dark, black shadows. While {
d tops of these mountains are glowing
y clear sunlight, the valleys, TO which I
D. Sinbeams cannot reach, are in darkne
ID When the sun sets, on the moon, I
II bright sunlight is changed into compile
?. darkness without the agreeable ira
ne sition of twilight.
ID Another phenomenon would be u
al known to the inhabitants OF the moo
ne if there were any. There is no bl
SIS sky to be seen there, but it is all da
~ and black, except in the neighborho
st of the sun. The same sad aspect OF t
at sky would prevail on earth if The
or were no dust But as it is now the dl
a' reflects the light and the finest Of
i'd particles cause the beautiful blue Co
ne by process called polarization and
be reference. Thus, the purer. the a
Mt where the fewest coarse dust partic
eey are in the atmosphere, the clearer a
IN bluer the sky.
ng We learn from all this that dust is I
- matter in the wrong place, not mer
m a nuisance to be got rid of, but that
in plays an important part in our life. I
'al crater of Vesuvius in Italy emits at
a times water vapor, invisible as all vaI
de is, so long as it remains vapor and
he not condensed to liquid condition.
~ approach the crater we burn SCI
IS. of paper near its mouth, and above
a crater hovers heavy fog. What is
reason? The ashes of the burnt pa
yield dust in millions of small particl
Around these the vapor condenses il
small globules of liquid water, every
'ly IS tboro non{o,p,po a duct ,,a ,t,oIo -,