62 CANINE DISTEMPER 
view of the fact that even a naturally contracted attack 
does not in all cases confer an active immunity. 
PREVENTIVE INOCULATION 
1. With Vaccine Lymph.—As early as 1795, Cae 
attaching great importance to the pustular lesions of 
distemper, advocated vaccination with cow-pox virus, 
which procedure was tried on various later dates by 
other .investigators, and renounced as_ ineffectual. 
‘Notwithstanding this, Dr. W. Brown, writing in the 
Veterinary Journal (November, 1902), observed: ‘For a 
number of years I inoculated all the puppies at Drum- 
pellier House, Coatbridge, with vaccine lymph, and with 
the best results. During my time I never heard of a 
case of distemper arising after inoculation. This was 
done at the request of Sir David Carrick Buchanan, who 
was a profound believer in the efficacy of the above 
treatment. I usually inoculated behind the ear, and no 
ill results seemed to follow.” His observations, however, 
have met with no support whatever, and such men as 
W. Sewell, Blaine, and Youatt before him, and A. Sewell, 
Hobday, and others after him, have expressed no un- 
certain opinions regarding the utter uselessness_ of 
vaccine lymph. 
2. With Crude Nasal Discharge.—Another early method 
was the inoculation of susceptible animals with the crude 
nasal discharge from a distempered dog, with the object 
of inducing a mild attack and its subsequent immunity. 
Unfortunately, however—as might be expected—a large 
majority contracted a more malignant type of the disease 
and frequently succumbed, so that the method was 
eventually abandoned. 
3. With Pure Cultures of Bacilli.—Investigations were 
pursued, and Semmer, in 1875, was the first to discover 
micro-organisms in connection with distemper. He 
