192 
DR. L. WALDSTEIN. 
experiments. The amount of oxygen remaining in the fluid is 
also considered by different authors a factor of greater or less 
moment with regard to the different forms of organisms or their 
earlier stages. The more recent investigations on this subject 
made known since the first publication of the present communi- 
cation, as well as those of the best authorities previously, have 
shown that as the different forms retain their vitality with varied 
tenacity under the influence of higher and lower degrees of heat, 
so many are more or less independent of the amount of oxygen 
present. It may be freely admitted that the greater part of the 
gas is well driven out of the retorts, but some may still remain, 
and if so-called germs and lower forms are yet within the fluid 
or adherent to the inner surface of the retorts or to the exterior 
of the liquor potassse tubes, they will find oxygen enough for 
their development. The unfavorable conditions into which 
such germs are brought by the treatment of the vessels and 
their contents, may well limit the degree of fertility ; on the other 
hand, as Dr. Bastian himself has found, the incubator tempera- 
ture of 122° B. (40 — 45° C.) is a very favorable agent. 
Notwithstanding the justice of these objections, which could 
be multiplied by an extended and a detailed reference to the 
Bacterium literature, w^hat would appear as most remarkable in 
Dr. Bastian^s numerous repetitions of the experiment, is the uni- 
formity of the difference between the contents of the retorts with 
urine and unbroken tubes and of those with the mixed fluids 
produced by breaking the potash tubes within the retorts after 
closure and ebullition. The critics of Dr. Bastian have singularly 
enough not laid the proper stress upon this, the real point at 
issue, for even if all their objections were just, the fact of such 
a difference would be all the more interesting. In their trials of 
the method they have not scrupulously followed his directions, 
and he is w^ll justified in refusing to accept their adverse state- 
ments for this if for no other reason. 
Before entering upon my own experimentation I would with a 
word call attention to the apparent unchanged condition of the 
fluid in the one set of retorts. I have found, and the same 
observation has been made by others, that the degree of turbidity 
is not in direct proportion to the multiplication of Bacteria. 
Certain specimens of perfectly clear and apparently unchanged 
fluids may swarm with organisms, whilst in turbid urine with 
much sediment few if any organisms can with absolute certainty 
be discovered with the microscope. This, it is true, is not the 
rule, but as it may occur the fact of an apparently unchanged 
apjiearance alone is not a sufficient test. It appears that the 
formation of so-called zoogloea masses is in most cases the cause 
of turbidity. 
