REPORT ON THE PREPARATION OF RINDER-
           PEST ANTI-SERUM BY MEANS OF
               DILUTED VIRULENT FLUIDS.*

                                   BY

PERCIVAL HARTLEY, D.Sc. (LONDON), I.C.V.D.,
    Physiological Chemist, Muktesar Laboratory.

The experiments described in the following notes were
carried out according to instructions issued by the Imperial
Bacteriologist. The various seras described were prepared
at Muktesar in November and December 1910 and January
1911. The serum tests were carried out at Bareilly in February
and March 1911.

The experiments were designed to investigate several
different points, one of the chief of these being to study the
nature of the serum produced by the injection of diluted virulent
fluids. In a series of experiments carried out at Bareilly in
the cold weather of 1909-10 by the Imperial Bacteriologist
it was noticed that subcutaneous injections of virulent blood,
diluted with potassium citrate solution 0.5 per cent. were very
rapidly absorbed. On the other hand, massive injections of defi-
brinated virulent blood are absorbed relatively slowly, and in
many cases the swellings created by the injection often persist
for many days. It was considered, on theoretical grounds,
that rapid absorption of the injected virulent material is proba-
bly a favourable factor in the production of seras of high potency
and the experiments were designed to investigate this point.
Another subject which was studied at the same time deals
with the question of the potency of the serum prepared by the
injection of virulent peritoneal washings. It has been stated
that the peritoneal washings taken from an animal at the height

                           * Results arrived at in July 1911.