Northern Wisconsin advertiser. [volume] (Wabeno, Wis.) 1898-1925, 1903-05-14
ALL BACTERIA ARE NOT BY ANY
MEANS BAD.
PERFORM GOOD SERVICE
Good" Organisms Whose Presence in
Water Warns Humanity that Evil
Species Are not far AWay-Curious
Experiments at Massachusetts In
stitute of Technology.


supply j. naturally one of the most i'm
portant matters that modern science
has to deal with. Until recently
chemical analysis has been considered
tho most authoritative method of APP
preaching the problem, while the
science of bacteriology- has to
do with the examination of the vast
number of little organisms that exist
in water-has been supposed to pc OF
less value. Within the last few years,
however, meteorological investigation,
largely as a result of what has been
accomplished at the Massachusetts
Institute of Technology, has been gen.
orally accepted by engineers and praC
teal sanitarians as quicker and more
direct means of learning whether
water is healtful or unhealthful-not,
indeed, by finding actual disease-pro-
ducing bacteria but by discovering
certain other organism whose pres
ence in large numbers is always proof
positive that the water has been pol
luted with sewage, and proof presump-
tive, of the presence of their more
dangerous brethren. The colon baciill
and the streptococci, as these tale
bearing bacilli are called, are not
harmful in themselves. In fact they
are distinctly friendly to mankind and
have given the scientists a rapid
method of finding the local source of
typhoid and other 6ater-borne cpl
denies.
Very few persons are likely to see
a colon bacillus even with a powerful
microscope, yet it is so widely diffuscd
that it exists practically everywhere.
But it only develops in large numbers
under special conditions of lighter
rather darkness-warmth, and nour-
ishment, and it is this strenuous and
patriotic development that makes 1T
such an excellent water test. If you
should examine drop of water under
a microscope the colon bacillus would
be one Of the many organisms that
you probably would not see at all be-
cause they were so small. Perhaps,
in that particular drop of water, if it
were very pure, there would be 70
colon bacillus whatever; but if there
was any pollution the little bacillus
would be there living upon it. And il
the proper conditions of warmth, dark
ness, and nourishment were provided
the bacillus would soon begin to di-
vide itself and produce what the BAG
teriologists call colony.
These colonies are the real test for
impurities in drinking water. A small
quantity of the suspected water
usually cubic centimeter, or, roughly
speaking, about thimbleful-ls
mixed with a solution that contains
nourishment for the bacillus and
certain amount of dextrose, kind OF
sugar which the colon bacilli not only
enjoy but have the property of caus-
ing to ferment. Tlis mixture is placed
in tube, shaped like the letter U
except that one arm is much shorter
than the other, and the tube put away
for 81 hours ii an oven heated to
blood temperature When the tube is
place. in the oven both ends are
closed, with the liquid entirely filling
the shorter arm If the colon bacilli
are present they will ferment the
dextrose in the solution, producing
gas that rises and forces the liquid
backward; so that when the tube is
again examined there is an apparently
empty space where the liquid had
been when the bacilli were first set
aside to incubate.
If you should now look at this solu-
- 1r01, would
probably see the colon bacillus, or
rather hundreds and hundreds of
them, hurrying here and there in the
mixture and looking for all the world
like miniature live sausages. But this
one experiment is not absolutely con
elusive; there is another little organ
ism. recently discovered III the In
stitute of Technology laboratories,
which destroys the colon bacillus ana
does not produce gas from the
sugary part of the solution-an or
qanism. in other words, which would
neutralize the experiment just de-
scribed. Actually to prove that the
colon bacillus was not present-with
Ali that its presence implies-ln the
original cubic centimeter OF water,
demands, therefore, a series OF other
tests made for the purpose OF diner
entiating this particular organism
from others which closely resemble It.
one of the simplest of these tests IS
70 grow the bacilli in gelatine thiliy
spread over a glass plate and shut az
in the mark at an ordinary tempeTa-
tire A little of me suspected water
Is mixed with the gelatine and il this
water contains bacteria, invisible even
to the rost powerful microscope. they
win Immediately begin to feed ana
develop. The colon bacillus grows oy
dividing itself into two similar organ
isms-a process which takes about ~
minutes under favorable conditions
and the colonies which result, having
more inhabitants than state IN the
American union. are plainly visible 10