THE APPLICATION OF QUANTITATIVE METHODS. 127 
various dumb animals—mingling the parasitic water with their 
food—proved failures. The hot season arrived, and it became 
necessary for Dr. Koch and his colleagues to return to Germany, 
without establishing the last link in the chain of evidence needful 
for the establishment of a theory the soundness of which the 
German scientists were convinced of. Happily the missing link 
has not much longer remained undiscovered. Dr. Vincent 
Richards, civil surgeon of Goalunds, has accomplished what Dr. 
Koch failed to do. According to a telegram received in England, 
the Calcutta Englishman announces that Dr. Richards has suc- 
ceeded in communicating what is believed to have been genuine 
cholera, by means of the cholera bacilli, to a pig, which died in 
three hours after the infectious matter had been administered. 
We have yet, of course, to learn how it happens that this experi- 
ment with a pig has so wonderfully succeeded while many previous 
experiments failed. But once successful, the experiment will no 
doubt be repeated until ample confirmation is obtained. In the 
meantime it will perhaps be comforting to English people to know 
that no “germs” of this kind are known to exist in connection 
with such diseases as dysentery and diarrhoea, which have a some- 
what strong resemblance to cholera. 
Koch’s extremely valuable discoveries at least indicate methods 
which would make it absolutely impossible for any known case to 
become the origin of an epidemic. As regards the probable mode 
of diffusion and with special reference to the discovery of the 
bacillus in tank water, it is significant that a cholera outbreak in 
Bombay which cost upwards of a hundred lives coincided with a 
three days’ stoppage of the Vehar water-supply through the burst- 
ing of a pipe, many of the people being compelled to have recourse 
to the wells in consequence. 
TRE APPLICATION OF QUANTITATIVE 
METHODS TO-THE STUDY OF CERTAIN 
BIDLOGICAL QUESTIONS. 
A Lecture delivered by H. C. Sorby, Esq., LL.D., F.R.S., at the Annual 
Soirée of the Manchester Microscopicai Society, February, 1884. 
R. SORBY said the subject of his Lecture was ‘‘ On the Applica- 
tion of Quantitative Methods in the Study of certain Biological 
Questions.” He thought it was pretty well admitted on all hands 
that the present condition of practical science was due to a large 
extent to the application of quantitative methods. These methods 
