486 
SOCIETY MEETINGS. 
that the human bacilli are incapable of affecting cattle ? This question 
is one of great importance to the sanitarian and will no doubt receive 
your most careful consideration. 
RECENT PROGRESS IN THE CONTROE OF ANIMAE DISEASES. 
Much has recently been accomplished in improving and adding to 
the methods available for the control of a number of our worst plagues. 
It is not many years since Texas fever was one of the most dreaded dis¬ 
eases, both on account of its destructiveness and of the mystery con¬ 
nected with its origin and dissemination. At last* this mystery has 
been cleared away, and we are to-day in a position to formulate more 
efficacious regulations for preventing this disease than is possible in 
connection with most others. By regulating the traffic in cattle from 
the infected district during the warm season of the year; by allowing 
them to be moved by rail only and for immediate slaughter during th^ 
season ; by segregating such cattle and disinfecting the cars in which 
they are transported, the losses from this disease in the Northern States 
have been reduced to an insignificant amount. 
There, however, remained other problems pressing for solution. In 
the vast district in which this contagion is enzootic, comprising practi¬ 
cally the entire area of six great States and one Territory, more than 
half the area of four other States, and important sections of two addi¬ 
tional States and one Territory,—in this extensive district, vast num¬ 
bers of young cattle are reared to be sold for grazing. It is very diffi¬ 
cult, as you will understand, to confine the shipment of these animals 
to the short period of two months in the winter season. The magnitude 
of the interests involved is a continual menace to the quarantine regu¬ 
lations. Fortunately we can now see our way to disinfecting these cattle 
so that they can be safely shipped anywffiere, at all seasons of the year, 
without conveying the contagion to other animals. 
Although these southern cattle carry the microbe of the disease in 
their blood for months and years after they leave the infected district, 
nature has beneficently provided that under ordinary conditions it can 
only cause disease when transferred to other animals by a single species 
of external parasite—the southern cattle tick or Boophilus bovis. With 
this fact demonstrated, it only remained to discover a practical method 
of destroying these ticks upon the southern cattle at the time they 
passed out of the infected district. This, however, was much easier to 
propose than to accomplish. Many preparations have been suggested 
and it was reported that one of these when tried killed the ticks imme¬ 
diately and the cattle in fifteen minutes. Other mixtures had no effect 
iipon either the cattle or the ticks. It may now be said, however, that 
in extra dynamo oil and sulphur we have a dip which kills the ticks 
with so little effect upon the animals that it can neither be objected to 
on the ground of financial lOvSs or cruelty. There maybe and doubtless 
will be further improvements made in the composition of the dipping 
mixture used for this purpose, but the point to be emphasized is that 
we nlvecidy have a dip which may now be successfully used for this pur¬ 
pose. 
There is but one other practical problem connected with the preven¬ 
tion of this disease, and that relates to the immunization of cattle that 
are taken into the infected district. You all know that the cattle of that 
