Small-Pox in Sheep, 
561 
just as susceptible to the vaccine disease as tho human subject — that 
not more than 35 per cent, of tho sheep, in our own experiments, 
proved to bo susceptible to the vaccine disease on a first vaccination. 
Inoculation the only Eeal Check to Sheep-Pox. 
I do not hesitate to say that when the natural disease appears in 
a flock, inoculation, properly carried out, is the best and the only 
sure means of arresting its ravages. It is not to be supposed that 
in advocating inoculation we neglect separation or segregation, or any 
other means of abating the severity of the disease, or that we intro- 
duce sheep-pox into healthy flocks. We only have recourse to 
inoculation that wo may bring the disorder within bounds, and cut 
off the supply by which the malady is naturally propagated. One of 
the good effects of inoculation is that it limits the extension of the 
disease. All animals that are inoculated will, in the space of about 
five weeks, especially if they have been dipped in a disinfecting mix- 
ture, be in a fit condition to be sold ; whereas, if the natural disease 
went on, it might be five or six months, or even longer, before such 
would be the case. Nobody indeed could tell when the thing would 
end. 
But some people say that inoculation spreads the disease. In 
the abstract there can be no doubt that the inocidatcd diseaso is 
infectious ; but it is infinitely less infectious than the natural disease, 
and practically, therefore, sheep-pox as a rule is not spread. Indeed, 
there is not a single instance in Wiltshire in which the disease can be 
said to have been spread by inoculation. On the contrary, it was 
hemmed in and limited to the flocks that became affected in the natural 
way. The reason why inoculation does not spread the disease is that, 
as a rule, and particularly when you arc dealing with young animals, 
such as lambs, it gives the disease in a very mild form. Take a 
hundred lambs, and if inoculation has been properly carried out, not 
more perhaps, than one in six or seven will be found to have any 
eruption at all on their bodies. They have the disease, so to speak, 
locally. But with old animals there is greater fatality. 
I have been at some pains to collect information, not only from my 
own experience, but also from that of others, with reference to inocula- 
tion in this country in the outbreak of 18G2, as also of that extending 
from 1847 to 1850, when there were more sheep in one part of Norfolk 
affected at one time than suffered in Wilts altogether. Thousands of 
sheep were subjected to inoculation in Norfolk, Suffolk, Essex, Kent, 
Cambridgeshire, &c, and I feared that the disease would be really 
naturalised among us, so widely was it then spread, but notwithstanding 
this, we had not half the hue and cry which was raised about only 
3000 sheep being affected in Wiltshire. Taking all the cases of inocu- 
lation together, I come to the conclusion that there have not been less 
than 20,000 sheep inoculated, and that the average mortality has not 
reached 5 per cent. In some particular flocks the mortality has not 
been more than 1 to 1£ per cent., and I can show instance upon instance 
in which it has not exceeded 2 per cent. ; but, combining the worst 
cases with tho best, tho deaths from inoculation have not attained 5 per 
