20 STORRS AGRICULTURAL EXPERIMENT STATION. 
belief that such is the case. Certain it is that the statistics as 
they are being collected in the last few years are tending to 
show that tuberculosis is not only on the increase, but on the 
very rapid increase. The amount of tuberculosis as it is de- 
termined by the sources of evidence already pointed out is 
becoming larger and larger each year. 
It is, however, difficult, if not impossible, to answer posi- 
tively the question as to what rate tuberculosis is increasing. 
The uncertainty of the sources of evidence which have just 
been pointed out apply with equal or even greater force when 
we attempt to answer this question. To such an extent is this 
true that statistical evidence upon this question is of very little 
value and, indeed, almost worthless. Of course it is evident 
at the outset that no facts derived from the tuberculin test can 
give us any idea of the increase of the disease, inasmuch as this 
test is so new that it is only just beginning to be used, and, 
since the tuberculin test will discover many cases that have 
hitherto entirely escaped observation, the data derived from 
this source give no means of comparison with the past. 
It might be supposed, however, that the data derived from 
slaughter-house statistics would be more significant, because 
inspection of the carcasses of slaughtered animals has been 
taken in some countries for many years. If these statistics are 
compared with those of earlier years, the results are to show a 
surprising and startling increase in the disease. “Twenty-five 
years ago the amount of tuberculosis reported from such in- 
spection was only three to five per cent. ‘To-day it is ten to 
fifty per cent., and more often approaching the higher than 
the lower figures. This increase of eight to ten fold in the 
course of twenty-five years is, of course, very suggestive, at all 
events. But even here we must recognize that the value of 
these figures is extremely questionable. We know perfectly 
well that at the present time our veterinarians are making the 
inspection with a great deal more care than in earlier years. 
They have learned to recognize incipient cases of the disease 
more readily. They note at the present time cases where a 
single swollen tuberculous gland is found, and in earlier years 
such instances would never have been noted at all. The great 
interest that has been attached to the disease has, in short, made 
the inspectors of cattle so much alert in discovering its presence 
in carcasses that it is doubtful whether the figures obtained 
to-day can be compared at all with those obtained twenty-five 
years ago under conditions in which the veterinarians’ atten- 
