294 BACTERIOLOGY. 
“(h) Cows should not be tested within a few days 
before or after calving, for experience has shown that 
the result at these times may be misleading. 
‘‘(i) The tuberculin test is not recommended for 
calves under three months old. 
‘<(j) In old, emaciated animals and in re-tests use 
twice the usual dose of tuberculin, for these animals 
are less sensitive. 
‘¢(k) Condemned cattle must be removed from the 
herd and kept away from those that are healthy. 
‘‘(/) In making post-mortems the carcasses should 
be thoroughly inspected, and all of the organs should 
be examined.”’ 
Tuberculin injections are also made in man to reveal 
a suspected tuberculosis. At first some believed that the 
irritation aroused in the tuberculous foci by the tuber- 
culin sometimes caused a dissemination of the bacilli and 
an increase in the disease. When carefully used, how- 
ever, in suitable cases there is probably no danger. A 
drawback to its usefulness is that it does not reveal at 
all the extent of the disease, nor whether the tuber- 
culosis is active or dormant. It is, however, of great 
value in selected cases, both surgical and medical, 
where slight tuberculosis is suspected, and yet no de- 
cision can be reached. I quote here Dr. Trudeau upon 
the use of the test. 
‘In the absence of any well-defined rules founded 
upon the experience of others at the time I began to 
use the test, the method I adopted has been a purely 
arbitrary one, and I make no claim for its being the 
best or the most reliable, although, as far as my own 
personal experience goes, I have as yet seen no objec- 
tion to it or any reason to modify it. 
