The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1920-10-10

she may have AZ many az Ave litters In
year. A litter consists Of about ten. A
female at the age of two and d half 10
three months is capable Of producing
litter. The young are very efficiently
tended so that scarcely sAt die.
Reproduction ceases during cold
weather. and rats can not reproeucs them.
selves al all In cold climates. I'd temper.
ate climates reproduction is Ut 4 stand.
still during the winter This most I'm.
portant factor limiting fepfvduction IL,
however, the supply Of nutfimsnt. A 10.
male receiving only sufficient food to keep
her in good eondition does not reproduce
at all, whereas with Representatives, Of
food reproduction proceeds 1T I'D maxi.
mum rate"
Professor Chavisny suggests to French.
men various methods Of combating sAss.
In view Of these facts enc ID more easily
sble TO understand why mass battle with
the rat has been SO little successfui Up to
now. The animal has until recently GOT
the better Of ID very decidedly. But In
this warfare sciencs has at last taken the
field, and we are beginning for the frst
time To know how we can defeat the TO.
dent enemy
Nothing couid be more simple. IN the
main, II is merely question OF cutting on
the rats food supply. The tightly covered
garbage can has been ordered by great
numbers of Psrisians. Remnants of food
in households must not be left about. AS
some wise person has said, HE who sows
food scraps win reap rat harvest"
Any dwelling house or other buildfng
can be made rstproof at small expense by
concreting the basement and area walls
and screening or otherwise stopping every
hole through which rat might enter. The
animals are thus deprived of harborage.
Even though there be rats on the premises,
the household supplies may always be kept
safe from them in rstproof containers
covered with wire net,
= Dontsoffer them food don't furnish then,
with hiding places. sars the professor. II
hungry they will eat poisoned bait of may be
trappedl but in either case the bait shosld
be high-havored (suoh a. tossted cheese
or bits of fried bacon), and should be OF
KIM uIleTenJ from any pr0Vender they
can obtain In the neishborhood The hest
traps are OF the "guillotine" pattern, with
wire fall released by baited sStwksr
The ratproofing Of a city II hardly more
than an extension Of the method adopted
for, the protection Ut q house II neces.
sarily embraces the treatment OF sewers,
which afford admirable runways for the
rodent pests, with supplies OF waste to
furnish provender. The sewers of Paris
have always been famous for their hordes
of rats, which in the days OF the siege OF
that city by the Germans, in 1871, proved
actually useful, furnishing the poor with
meat supply.
All the trouble in Paris and In other
parts OF the world Is due to one species
OF rat-the big brown rat. Il is not an
aboriginal native OF either Europe or
America. II came originally from ksis
and did not appear In Europe until the
seventeenth century and IN America until
about the time OF the Revolution. All
other species OF rats are comparatively
mild and harmless and give way before
the brown rat
Il is estimated that the rats now sfhict-
Ing Paris are eating up food sufficient 10
maintain 100000 people annually. II left
unchecked the rats would certainly drive
man of the face of the earth.