560 
PIERRE A. FISH. 
lowing day. The experiment was repeated in July, 1898, with 
a two per cent, solution from another bottle of creolin with the 
result that no growth developed. 
Formalin.—This agent was used in the proportion of 1-1000 
and after four days the tube remained as clear as when sterilized. 
The experiment was repeated in 1898 with the same results. 
Slater and Rideal’s re-examination, in which formaldehyde 
was added to tubes of bouillon in proportions varying from 
1 in 1000 to 1 in 20,000, the tubes then inoculated with vigor¬ 
ous cultures of different micro-organisms, and placed in an incu¬ 
bator showed the results for inhibitory action, as on preceding 
page. 
It is to be noticed that even when the proportion is too small 
to prevent growth, the cultures then obtained are scanty, and 
their development is long postponed. The fact that growth 
does not take place in the bouillon is not proof that the microbe 
has not been killed. Thus bacillus mallei which showed no 
growth after four days incubation in a 1-15000 strength, when 
transferred to a fresh nutrient solution gave rise to a culture 
normal in all respects, except in requiring an unusually long 
time to develop. 
Hydrogen Dioxide.—This agent was used pure and also in 
the proportion of 1-500. With the former no growth appeared 
after seven days, but with the latter, growth developed within 
18 hours. 
Lysol.—A 1 i solution was used. Growth appeared within 
twenty-four hours. The experiment was repeated in 1898, with 
a 2 io solution from another bottle, and no growth appeared. 
Mercuric Chloride.—Proportions of 1-1000 were used, and 
growth appeared in the lower half of the tube, upon the fol¬ 
lowing day. The experiment was repeated in 1898 and the 
tubes remained clear. Rideal (4) reports that Klein considers 
mercuric chloride an efficient germicide, but maintains that 
Koch and others have overrated it. In 1885 Blytli conducted 
a series of experiments in which he treated anthrax spores with 
1 in 1000 solution of mercuric chloride as others had done, 
