136 Annual Report of the Royal Veterinary College. 
individuals, and as soon as the fact was published veterinary sur- 
geons both at home and abroad may be said to ha ve jumped at the 
idea that tuberculin might render immense service in the diagnosis 
of tuberculosis. Experiments in this direction were immediately set 
on foot in almost every European country, and numerous reports on 
the subject have appeared within the last two years. The tenor of 
these reports is by no means uniform, but the great majority of them 
were favourable to the employment of tuberculin as an aid to the 
diagnosis of tuberculosis. During the past year over a hundred 
cattle, some obtained specially for experiment, and others belonging 
to members of the Royal Agricultural Society, have been treated 
with tuberculin, but, before stating the general result, the mode of 
administration and the rationale of its employment may be explained. 
Tuberculin is an amber-coloured liquid prepared and dispensed 
under the authority of the German Government. It is administered 
by subcutaneous injection, and the most marked effect to be looked 
for in tuberculous animals is an elevation of the body temperature. 
When it is intended to use it for diagnostic purposes on an animal, 
the temperature must be taken once or twice during the twenty-four 
hours before the injection is made. The normal temperature of the 
ox is about 101° E., and it is only exceptionally that this temperature 
is much exceeded in tuberculous subjects. During the next twenty- 
four hours after injection the temperature is taken at intervals of 
three or four hours, so as to detect any elevation that may be brought 
about by the tuberculin. Not rarely the temperature rises to 105° 
or more, and sometimes this is accompanied by other signs of fever, 
such as hurried breathing, restlessness, and loss of appetite. The 
dose required to bring about this febrile reaction is comparatively 
small — about half a cubic centimetre for a cow or ox of ordinary size. 
The diagnostic value of the agent lies in the fact that such a dose 
is without appreciable effect on an animal that is not the subject of 
tuberculosis, while it determines an appreciable rise of temperature 
in animals that are tuberculous. In the experiments here referred 
to various doses were employed, and the result appeared to show that 
no advantage was gained by using larger doses than the one above 
mentioned. 
It would be out of place here to give in detail the observations 
made regarding the temperature of all the animals that were treated 
with tuberculin, but the general result may be briefly stated. 
Seventy-two of the animals have been killed and submitted to 
post-mortem examination since they were treated with tuberculin. In 
thirty-two of these animals the temperature after injection rose to 
103° F. or more ; and, in twenty-seven of these, lesions of tuberculosis 
were discovered, while in the remaining five no such lesions could be 
found. Of the forty animals in which the temperature after injec- 
tion remained normal, or at least did not rise to 103° F., twenty-one 
appeared on post-mortem to be free from tuberculosis, and in the re- 
maining nineteen lesions of that disease were discovered. The results 
in the case of these seventy-two animals may be otherwise stated 
thus : The tuberculin pointed out correctly the existence of tuber’ 
