Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-08-20
MICROBES AS RAT TRAPS.
Germs Pitted Against the Vermin and
Score a Triumphant Victory.

From the Philadelphia Record.
In certain portions of the agricultural dis
tricts of France the depredations OF rats
and mice have been so extensive that the
losses arising therefrom have been little less
than a plague The attention of the OFF,
Gals in charge OF the Pasteur Institute
was called to the matter and they were IN
duced to attack the problem, which they
did with such eminent success that medal
in recognition OF their services has been
awarded 10 the institute by the government
through the minister of agriculture. This
recognition took the form of the award OF
a mucl.-prized decoration to the manager of
the institute and another to his assistant.
These rodents swarmed the fields and In
vaded the houses of the farmers. In many
cases smaller specimens of the domestic
animals were attacked and killed and par
TALLY devoured by the overwhelming
hordes. 1t was common experience for a
farmer to find entire field Of truck
RUINED by the animals. which sometimes
ate the roots of the plants and at other
times selected the stalk.
The problem which confronted the
perts of the Pasteur Institute was to devise
some method Of killing the rats without in
Turing the other domestic animals which
might be found around the farm They
have certainly succeeded in finding the
means of wiping out the rodents, but there
is some doubt yet whether the poison will
not have some serious effect on other ami
lIlGlS WHICH might ucNOuT Tie Sup.
Having made up his deadly dose Of mi
crobes. DR.. Roux prepared for battle
royal with the rats. The ground selected
for this mortal combat covered 1905 acres,
Oradour and Mons. Here various kinds of
cereals. vines and trees abound, and here
also the sowing of various kinds of grain
last autumn had been completely destroyed
by these rodents. This meant also the de-
struction of fodder for cattle-such as lu-
cern-hence, butter and milk production
was seriously affected. The ground through
out the district was literally perforated
with holes, which seemed to be connected
underground with little passages. Such was
the condition Of the scene of operation of
DR.. Roux which certainly seemed to offer
severe test for the efficacy Of his discoy-
cry.
DR.. Roux succeeded in. interesting the
farmers of the district in these very i'm
portant experiments, and soon the cele-
brated scientist had organized corps of
assistants on the spot These assistants
under the direction of DIR. Roux, dipped
quantities of wheat, oats and pieces Of
bread into the bouilon, and which conse-
quently became Immediately impregnated
with the microbes which the bouillon or
soup contained.
Then the poisoned wheat etc, was placed
In and about the holes where the rats and
mice were known to be. The total quantity
of poisoned paste" distributed amounted
In all to AZ metric tons Of bread and 90
metric tons of oats, while the quantity of
-
total area Of these experiments, as above
indicated, was 1855 acres.
10 determine the effect Of this poisoned
paste on these destructive little animals
DR. Roux had the fields that had been mi
crobe treated plowed up in order to see the
condition of the rodents after they had
eaten the paste and to fix approximately
the number of ra is and mice that had suc.
cumbed 10 the poison. The results obtained
surpassed all expectations on the part of
the simple farmer. Rats and mice were
dead in almost alarming quantities. and be-
came quite as much of a pest when dead
and putrefying as when they had been
alive, but, happily, In another sense of the
word. DIR. RouX estimates that he de-
stroyed no less than 95 per cent of the ro-
dents by these experiments. AS many as
fifteen to twenty rats were sometimes found
in one hole.
Not satisfied with this ocular demonstra-
ton of the success of his paste, DR.. Roux
proceeded to field of an ara of about two
and one-half acres and surrounded by vines.
here he had number of rat holes counted
this number being fixed at 124S4 which
We're carefully closed. Two days later the
holes were again visited. and it was found
mat I,5'4 had been reopened by the rats
Inc poisoned paste was again brought into
requisition. Eight days afterward the field
was again visited and the holes which had
Deen opened counted, the process being re-
peated two days later. The holes that had
been opened by the rats were found to he
thirty-seven.
me minister of agriculture, on being sat-
lshel with the results thus obtained by DR.,
Roux, and acting on the advice of the emil
nent scientist, proposes to Introduce into
the chamber of deputies a bill for the pur-
pose of compelling farmers In rat,nfested
districts to cooperate in using the above
described D3Sta