644 
LECTURE ON THE DISEASES OF CATTLE. 
are generally found existing. In a domesticated state all animals 
are more prone to disease than they would be in a natural state ; 
but we find that those animals who live in the closest approxi- 
mation to a state of nature are still greatly disposed to disease. 
For example, a sheep lives in a nearer approximation to a natural 
state than any other of our animals; yet with how many diseases 
is it afflicted, and what ravages are frequently made in a flock ! 
From three to six per cent, may be taken as the average annual 
loss in that class of animals alone ; and at that ratio we sustain a 
loss of £1,500,000 per annum. Besides, we must look at the 
state of the animal in progressing towards a condition in which he 
will become fit food for man. We must look, first, at the animal 
itself; secondly, at the loss of food which would be useful for 
another animal ; and, thirdly, we must take into account the money 
required to replace that which has been lost. We must embrace 
in our calculation not merely the loss of an animal, but the capital 
required to replace our loss. 
The question arises, as to the best general treatment of animals ; 
but before I proceed to that, I will make a few observations with 
regard to the spread of the epidemic. The first trace which I had 
of the malady was in the year 1835. In that 3 'ear it commenced 
individually, and terminated in death after an illness of several 
months; however, very few cases occurred, and what took place 
in that year was only the avant courier of what was soon to follow. 
The matter went on thus until the following year, when I was 
called upon to attend that which appeared to me a new disease. 
The first patient that I had under treatment for this disease shortly 
died ; and the investigation after death shewed the nature of the 
disease. Other cases rapidly occurred, and in July and August, 
1836 , the characters of the disease were rapidly developed. The 
first case occurred in Berkshire, just on the borders of Oxfordshire ; 
and the disease next appeared to me at Brixton Hill, in Surrey. 
If you draw a line on the map, you will find that the disease pro- 
ceeded as nearly as possible from east to west. In about two months 
it reached London. This was the malady under which horses suf- 
fered. In the following month of January it had got such a head 
that its ravages attracted great alarm ; the frost, which was rather 
severe, brought it out with terrific violence, and the whole king- 
dom was suffering under it. But still, up to that period, other 
animals had escaped. 
About this time I began to turn my attention to sheep, finding 
them in large numbers, and in a more favourable position for the 
investigation of disease than animals kept under corn, or treated 
artificially. In 1840 the disease broke out amongst horses and 
sheep simultaneously. I speak now of my own immediate dis- 
