208 
PROGBESS OF MICROSCOPICAL SCIENCE. 
acid or alkaline at a temperature of 158° F. (70° C), is correct, then 
the occurrence of fermentation in the previously neutralized boiled 
urine would similarly disprove the exclusive germ-theory of ferment- 
ation and establish the occurrence of Archebiosis. Any difficulty 
which might have been felt by others in accepting the above interpre- 
tation of the results of these latter experiments — in face of the view 
held by M. Pasteur that some Bacteria germs are able in neutral 
fluids to survive an exposure to a heat of 212° F. (100° C.) — has been 
fairly met and nullified by the experiments (devised for the purpose), 
in which the urine was boiled in the acid state and subsequently 
fertilized by the addition of boiled liquor potassae. If we look at 
these latter experiments from an independent point of view, it will be 
found that this fertilization of a previously barren fluid by boiled 
liquor potassse must be explained by one or other of three hypotheses : 
1st Hypothesis. The hoiled liquor potassce may act as a fertilizing 
agent because it contains living germs. — However improbable this hypo- 
thesis may seem on the face of it, it has been actually disproved by 
many of the experiments recorded in this memoir. These experiments 
show that boiled liquor potassaB will only act as a fertilizing agent 
when it is added in certain proportions. If it acted as a mere germ- 
containing medium, a single drop of it would suffice to infect many 
ounces, a gallon, or more of the sterilized fluid. This, however, is 
never the case. 
2nd Hypothesis. The fertilizing agent may act hy reviving germs 
hitherto presumed to have been hilled in the boiled acid urine. — The 
acceptance of this hypothesis would involve a general recantation of 
the previously received conclusion that Bacteria and their germs are 
killed by boiling them in acid fluids. But such a recantation would 
be scarcely justifiable or acceptable unless based upon good indepen- 
dent evidence. The possibility, however, of accepting this second 
hypothesis is still further closed by the results of experiments in 
which a slight excess of liquor potassae was added to the boiled urine. 
Such fluids invariably remained barren. 
drd Hypothesis. The fertilizing agent acts by helping to initiate 
chemical changes of a fermentative character in a fluid devoid of living 
organism^s or living germs. — If the cause of the fermentation of the 
fluids in question does not exist in the form of living organisms or 
germs either in the fertilizing agent itself or in the medium ferti- 
lized, then it must be lound in some chemical reactions set up 
between the boiled liquor potasses and the boiled urine. 
A New French Worh on the Microscope has just been published by 
V. Masson, of Paris. It is entitled * Lei Microscope, son Emploi et 
ses Applications,' by Dr. J. Pelletan, with 278 figures and 4 plates. 
In reference to this book the ' Lancet ' (Aug. 5) says : — " Microscopy 
has taken its place among the refined recreations of cultivated society. 
In the study, sometimes even in the drawing-room, the youth acquires 
a familiarity with the instrument which will yield many an hour of 
intellectual amusement in his rural or seaside villeggiatura. If pre- 
paring for the medical profession, he will at once feel the benefit of 
having thus early familiarized himself with an implement which has 
