New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1897-01-24

the tissues Of the victim but indirectly that Is to
say. that the bacterum secreted poison. and
that the latter did the work 1t was this poison.
or toxin. and not the living germ, which he in
PRODUCED into the horses veins. DIR. Yersn and
his associates followed the same general method.
but began by trying to immunize rabbits and
guinea pigs. and then larger animal.
A FAILURE AND A SUCCESS.
At first. then. the Frenchmen decided to filter
out the living germs from the culture. and to em-
ploy the residue for simultaneous injections.
But this fluid had no effect whatever. 1t was
deemed necessary. therefore, to introduce the
dead bodies of the bacteria into the system Of
the vaccnated animals. The culture carefully
Enclosed in sealed tubes. subjected for
whole hour to "A temperature of 134 degrees Fair.
This Killed the germs themselves but the fluid
was nevertheless more or less poisonous. In fact.
IL enough OF II were used. being injected into
either the veins or abdominal cavity, a rabbit or
guinea pig could be killed outright But only
moderate doses were employed-Dr. Yersin does
not say exactly how much. but it was enough TO
make the animal sick. yet without causing death.
However, he subsequently found an injection
merely under the skin preferable TO the other
method. Three or four such injections, al hf-
teen-day intervals. sufced to render a rabbit
proof against an incubation with virulent ba-
GILL. The guinea pig was found to be rather
more difficult subject. 1t could be immunized
only rarely
The next step to test the serum of the
this fluid were injected simultaneously into
fresh land healthy rabbit This was sufficient
to render the animal insensbe to a subsequent
incubation that otherwise would have proven
fatal Indeed If the amount of serum from
imn.unized animal were Injected into another
fully twelve hours after fatal dose had bee,
administered. 1t would arrest the propagation OF
the microbes in the nOculated subiec' and
actually cure the animal. Thes, results were 50
encouraging that ii was now resolved to try a
horse.
In this experiment live germs and not
cooked culture used The full strength OF
the fluid preserved. The quantity intro
duced at single injection was sufcien: to Kill
q mouse in TWO days. The fever excited by this
dose developed rapidly and was intense IT con.
tnued for week Twenty days were allowei
to elapse however. before another incubation
was attempted. This time the same quantity
was injected. Again a decidedly feverish re-
action was produced, but ii did not last so long
as before Later larger doses were given. and
al shorter intervals. The treatment continued
for nearly six weeks. Serum from the horse
then tested with mice. rabbits and guinea
pigs. The best success was attained with the
mice which Dr. Yersin was inclined 70 think.
Nigh: have been due to the fact that the virus
introduced into the horse came from mouse
If the immunzing dose were administered be-
fore the virulent injection, only one-tenth OF
cubic centimetre used on mouse; but II
twelve hours afterward as much as fifteen CEN
timotres.
YERSIN'S RETURN TO CHINA
Leaving Paris after he had reached this stage
of his work Dr. Yersin proceeded 70. the French
possessions in Southern Asia and set up new
laboratory at Nha-Trangs. m Isolated point on
the coast Of AMMAN Here he produced serum
with which he believed 1t possible to immunize
a human being. Early in 1896 the plague reap
reared in China Yersin hurried thither. TAX
ing with him little of his antioXn In sealed
tubes But the Chinese were unwilling 10 he
treated by a European doctor. such were their
intense preiudces. However, after little, the
Frenchman found three native students az
mission in Canton who had been stricken with
the plague and who We're willing to put them
| selves in his hands They all promptly recOv-
| cred and attributed that happy result to the