347 
and contained no organic forms excepting those proper to the 
liquids. They were then carefully mixed with boiled dis- 
tilled water by the aid of a freshly prepared pipette, and 
again covered with cotton wool. [On April 3 the liquid was 
entirely free from microzymes, and exhibited no sign of 
decomposition.]! The blood contained in the eprouvette was 
allowed to coagulate, and yielded a clot and very limpid 
serum. Up to March 30 it remained quite unaltered, and 
on microscopical examination it was found to be quite free 
from microzymes. On that day the serum was transferred 
by means of a superheated pipette into another superheated 
eprouvette, and diluted with boiled and cooled distilled water: 
it was then placed in the incubator. To the clot distilled 
water was added in quantity corresponding to that of the 
serum which had been abstracted: it was placed in the incu- 
bator. [When these preparations were examined on April 3, 
the serum was still limpid and perfectly free from organic 
forms, and the clot-preparation showed no change.] 
Other experiments were made, consisting in impregnating 
charged eprouvettes with drops of blood taken directly from 
the finger, great care being taken in each case to cleanse the 
surface of the skin where the puncture was made. In each 
case the blood-corpuscles subsided to the bottom of the eprou- 
vette, leaving a clear liquid in which no development of 
microzymes took place, although they were kept under obser- 
vation for several weeks. 
We have no hesitation in attributing the development of 
bacteria in the liquid in the test glasses marked a, a, to an 
accidental contamination (e.g. to the falling into the glass of 
a hair of the rabbit, or possibly a drop of saliva), and in con- 
cluding that normal blood contains no microzymes potentially 
or actually. 
XXII.—February 24.—A guinea pig was killed, and, 
immediately after, the integument was stripped off the back. 
Portions of the muscles and cellular tissue of the rump were 
then rapidly cut out with scissors which had just been heated 
in the flame of a Bunsen’s lamp. The pieces were then 
seized with the aid of glass hooks which had just been made 
for the purpose, and transferred into charged eprouvettes 
(marked @). Others were placed in superheated test glasses, 
and covered with boiled and cooled distilled water, but by 
accident one of them fell from the hook on to the table 
(marked 6). The skin was then stripped off the thighs, 
which were immediately separated from the body with the 
1 The Report bears date March 31st, 1871. The passages in brackets 
were added during the first week of April. 
