Evening star., 1916-12-03

61HE United States public health
service in two years down in
III New Orleans has trapped 900.-
900 rats and disposed of almost
as many more by poison and starvation.
They have SO thinned them out-or
educated them in the art of concealing
themselves-thatn now report of eight
cen or twenty rats a day is good
catch.
The most effective way of Kidding the
city has been to tear down rookeries
and to rat-proof buildings; or, as
Surgeon General Blue more forcibly
puts it. they have built the rats out of
existence"
The rat-catching corps were scouting
out rats on a governmental scale to learn
where some measly little bacilli come
from. OF the rodents they caught they
dissected and examined $4,000, and
in 346 of them discovered what they
were in search of. In fact they found
two things plague bacilli inside the
rats and ieas in their fur, Whereupon
the savants cried Eureka"
The bacilli infect the rats: f1eas suck
their poisoned blood and then bite hu-
disease, the much dreaded bubonic
plague. They also bite other rats and
thus keep up the chain of destruction
BY freeing some of the captives care
fully marked the plague-hunters learn
ed the radius of action of the broods
and laid their plans accordingly.
Neither feas nor germs can be caught
without first catching the rat. but that
is not an easy thing to do. Still he is
go destructive pest as wen as danger
Gus carrier of disease that il was de-
termined to make the effort: and it was
done thoroughly with the aid of a thou
sand men. with traps, dogs. picks, show
els. poison. dissecting knives, micro
scopes and above all. brains and a sys-
tenn.
from a community. They are SO clever
at hiding that men and dogs, ferrets
and cats cannot catch them all; and
the survivors and new immigrants
breed SO rapidly that a new supply soon
takes the place of those lost in the
conflict.
The only way is to build them out"
of their nesting and feeding places by
making houses, barns. warehouses and
wharves rat-proof. and this is what
these scientific rat-hunters did to the
cities of New Orleans and San Fran
cisco to protect them and the whole
country from the bubonic plague.
The most common rat in this country
is the brown fellow, who came over
black rat In about the same way that
the white immigrants from Europe
have run the aboriginal red man out of
the best part Of the country.
Rats-a popular belief to the con-
trary-are not very dangerous to hu-
man beings They will not fight
against man. unless driven into a cor
ner. and their bite is not poisonous.
Their tncisors, two in number, are
long. chisel-shaped, with enamel on the
front only. SO that the wearing away
Of the soft back keeps them sharpened
to a chisel edge. They are not often
sive weapons. but as gnawing iustru-
Inents cannot be surpassed. for with
them rats cut their way easily through
oak boards clay brick, pieces of slate
and almost anything else short of
metal or stone. In Germany. the home
OF efficiency, they gnawed the feet of
three elephants so badly that the
beasts had to be put to death.
II is very difficult to make a census
OF the rat population. and IT will vary
considerably in A short time. for II has
been estimated that one pair under
Ideal conditions may become the Adam
and Eve of 100000. 900 rats in Ave
years.
The estimate made by commissions
of various countries is that the rat
population about equals the human
population In numbers. and the de-
struction done by the average rat an
nually is about 81 so. which means in
this country that they cause waste
of al least se00.0 900 a year. besides
the harm done by the diseases they
spread. SO that 1t would be economy
10 spend many millions year II they
thereby could be eradicated or even
greatly reduced in numbers
They have nothing whatever to their
credit: for. except the act of the
mouse which freed the lion, there Is
no record of anything good in their
favor: and that story is fable: 1t
was not about rat and nobody knows
how much harm the lion did after he
was loose.
The proposition has been made TO
start combined cat and rat farm.
where the cats eat the rats and the
rats live on the cats. leaving the cat
skins clear profit: but IL has never
been worked out commercial
scale.
} The greatest direct damage rats do is
to eat grain. both in the fields and in
the elevators and storehouses; but they
also steal chickens, ducklings. meat,
peanuts. milk and all kinds of food
from the family larder. They carry OF
eggs by the dosen without cracking .