The Bennington banner. [volume] (Bennington, Vt.) 1858-1894, 1890-12-18
HOW DR.. KOCH REACHED HIS DIS.
COvERY.

The recital of the manner in which DR..
Koch arrived at the stage in his grand
discovery where he thought it safe to in
oculate human beingsis very curious and
interesting. There is q certain analogy
between these curious experiments and
those made by Pasteur and Edison, along
different lines, but also in seerch of ire
mendous results.
First, DIR. Koch, recognizing that
phthisis is caused by the tuberculosis,
which in its turn is caused by microbes,
and that the old treatment of phthisis
had few healing effects, decided entirely
to abandon the beaten track. 81 will
not" he said, "make upon human be-
ings experiments which at the outset
can have but little value" l will begin
with the bacillus in cultures which l
have myself prepared" Then began the
vast experiments which have been GER
tainly carried on since the outbreak of
the cholera at Marseilles in 1885, and
possibly much longer, and which have
demanded almost infinite patience.
Dr. Koch prepared certain number
many hundreds-of simple glass tubes,
which caused to be sterilized in fire. He
then filed them with cultures, also steT-
ilized, that is, with cultures which con-
tanned no germ. These were prepared
with Agar-Agar, kind of gelatine. Mi
crobes taken directly from the expector-
alton of consumptiye patients were then
placed in this "boullion," and the mouth
of the tube was carefully closed with
cotton, in such manner that air might
pass in, but that organisms in suspen.
sion were kept out. Each receptacle
thus impregnated was submitted to even
temperature in an oven,
After a little the microbes snwn In
these cultures began to develop, to
swarm and to take the ''colony" form
characteristic of tuberculosis. Now
came the work of shifting from culture
to culture-an almost endless task. re.
quiring minute attention, as fruitful ex.
periments can be made with pure cul.
lures only, that is with those containing
only the one micrObe which is to be
studied. The shifting had often to be
carried on as many as fifty or sixty times
in the case of each culture.
As soon as he had his pure cultures in
hand, DR.. Koch tried great number oil
chemicals reagents upon them. In the
series of others he tried etherized oil
Among the aromatics he chose naptha
lamine L, -paratolindine, xylicine, fusch
inc; among the coloring agents violet
metylene blue, chrome yellow, aura
mine; and among the metals tin, silver
and gold.
In this latter metal he found the mos
energetic action. At the end of severa
thousand interesting experiments HI
found that solution of one or twO-mil
lionths of cyanic chloride of gold wOulC
stop all development of the bacillus in
pure culture.
He now considered that he had arrived
at the conclusion of the first stage of hi,
journey. The next thing was to expert
ment on animals with the substances
which served to arrest the development
of the bacillus. He chose guinea pigs
because they take phthiSis very readil,
after incubation, and on guinea pig
which he had inoculated with the dis
ease, he experimental with all the chem
ical reagents mentioned above. Not on,
of them, not even the chloride from
which he had expected so much, was O.
any avail. and all the little animals dice
of phthisis. But the doctor did not los,
courage; he began second series of ex
periments on animals, and after vas
trouble he succeeded in finding sub
stance which was as effective on the ami
mails as the chloride of gold had proven
in the cultures.
This is the substance which DR.. Kocl
has finally adopted, and which he reso
lutely keeps secret. In the second Sc
ries of guinea pigs inoculated with til,
tuberculosis, the bacillus was killed anC
all the animals got we'll 1t was at thu
close of these experiments that DR.. Kocl
made his celebrated announcement a
the International medical college il
Berlin last August, that microbes in thu
animal economy might henceforth b,
paralyzed without danger. But he die
not then say that he had made any ex
periments upon human beings, nor tha
phthisis in human beings was durable
He announced nothing which he did mo-
know. Shortly afterward he began hii
experiments upon human beings, EN-
ploying the same substance which hi
had adopted in the case of the guinea
pigs. His resolution to keep the exact
nature Of this substance secret until cures
of phthisis in the human race by thil
process we're beyond peradventure, has
not been broken, and it is probable thai
months will yet elapse before he will tel
his secret.