324 THE SEVENTH INTERNATIONAL CONGRESS OF VETERINARY SURGEONS. 
By this method a film can be made upon a slide or coverslip 
which is free from fat and proteid grannies, and contains only 
the bacteria present, together with any solid debris which may be 
in the milk or other fluid. To get rid of this foreign matter, if 
present in any large amount, one may safely filter the fluid at the 
beginning of the process through the finest gauze. It is wholly 
unnecessary I find to treat milk with sulphuric ether in order 
to separate off fats, the caustic potash being useful to remove 
both fats and proteids from the deposit after the first centrifu- 
galization in a way that is completely satisfactory. 
I have employed this method and have been able to detect 
bacilli in the milk in which they were present in such small 
numbers that, by inoculating 15 to 33 c.c. of the same milk into 
a series of over 50 guinea-pigs and rabbits only in one animal 
(rabbit) was there a development of tuberculosis, and I will go 
so far as to say that this fact indicates that the method affords 
a more sure diagnosis of the presence of bacilli in milk than 
does inoculation. It may be added that from using this same 
milk I have concentrated down 70 c.c., using distilled water, and 
in weak caustic potash have inoculated the deposit into a rab¬ 
bit which now after 14 days is showing definite emaciation and 
indications of the progress of tuberculosis. 
It is scarcely necessary to add that this simple method can 
be most satisfactorily employed for the detection of tubercle 
bacilli in other animal fluids ; it gives excellent results, for ex¬ 
ample, with sputum from suspected cases of tuberculosis, and 
although as yet I have had no undoubted example of tubercu¬ 
lous urine, I have found that it gives a very clear precipitate of 
bacteria in urines containing a large amount of mucous and 
pus. 
THE SEVENTH INTERNATIONAL CONGRESS OF 
VETERINARY SURGEONS. 
We have received from the Committee of Management the 
following circular of information and programme of the subjects 
