1889-90.] Dr Griffiths on Researches on Micro-Organisms. 259 
more than 250 grammes, and it is only slightly more 'poisonous when 
injected subcutaneously” 
These results have been confirmed by Dr J. Maximo vitch 
( Comptes Rendus , vol. 106, p. 1441). We may, accordingly, conclude 
from the above investigations that /3-naphthol is a true germicide, 
and is capable (to a certain extent) of being injected into the system 
without toxic effects. 
We have thus at our command several reagents which have been 
proved to destroy the microbes of some of the worst forms of disease 
which afflict man and animals. We may then, perhaps, look for- 
ward to physicians putting into practice the ideas given in these 
papers of destroying the disease germ by the injection of a germi- 
cidal agent. 
At this point, we consider the action of certain reagents on the 
growth and development of various microbes. 
(a) Bacillus tuberculosis. 
I have found (for a second time) that solutions of salicylic acid 
(natural), potassium iodate, and sodium fluosilicate (in the propor- 
tions already mentioned in this paper) destroy Bacillus tuberculosis. 
It is impossible to inoculate tubes containing sterilised blood 
serum plus 3 per cent, of salicylic acid with Bacillus tuberculosis from 
a pure cultivation or from sputum (from the worst form of phthisis). 
This clearly shows the germicidal nature of the reagent. I have 
performed the same experiments with Bacterium allii , Bacillus sub- 
tilis, Bacillus oedematis maligni , and Deneke’s Spirillum , and found 
that their growth was inhibited in a precisely similar way. 
(b) Bacteria of Infantile Faeces. 
On April 13, 1888, Dr Baginski read a paper, before the Berlin 
Physiological Society, on the cultivation of Bacterium lactis (obtained 
from infantile faeces) in a sterilised solution of pure milk-sugar. 
After fermentation, no lactic acid but acetic acid was found as 
the result of the life-work of the micro-organism in this particular 
medium. The microbe in this medium is both aerobic and anaerobic, 
and always produces acetic acid. The gaseous products of the 
fermentation are carbonic acid gas, hydrogen and marsh gas. 
Baginski says that when the microbe is cultivated in gelatine, 
