162 
PERIODICAL OPHTHALMIA 
this soil during the three years the army of occupation remained 
in France, subsequent to the battle of YVaterloo. The contractors 
employed by the French government to furnish the British troops 
with forage, &c. purchased a great pail of the corn for the cavalry 
horses in Normandy, whence it was brought along the coast, for 
the most part, in open vessels, and thus subject to get damaged 
with wet in the transport, particularly during the rainy summer 
of 1816. It was landed at Boulogne, Calais, and other places, 
where it was put in store, generally heaped up to an immense 
thickness, and consequently soon became heated ; sometimes to 
such a degree as, in a short time, to be literally half rotten. In 
this state it was either offered to the troops, or forced upon us, 
when mixed with a portion of better, so as to give it a more 
plausible appearance. Complaints were continually made, and 
investigations set on foot; but still this grievance was never en¬ 
tirely removed : the oats always presented a more or less unsound 
mixture, giving to the whole the character of an unwholesome 
food for horses. The consequence was, that diabetes was always 
a very general complaint amongst our horses, but more especially 
in 1816, during which year it often prevailed to a most frightful 
extent . We endeavoured to check it by mixing chalk in the 
water, and by giving all kinds of astringents internally:, for 
common use, I generally found the following formula satisfac¬ 
tory : R powdered galls, alum and bole, each 3j, ginger si, in a 
quart of beer; to be given by way of drench, or in the form of a 
ball, divided into two parts, and to be given morning and evening. 
Every one knows that the common symptoms of diabetes are, . 
excessive staling, accompanied always with insatiable thirsty and 
wasting away of the flesh ; but to these we had often also added, 
loss of appetite and great constitutional disturbance. It was 
when these last symptoms were present that I remarked an at¬ 
tack of inflammation of the eyes was very apt to supervene, and 
which afterwards never failed to recur by paroxysms, putting on 
the regular periodical character. Of this extraordinary and la¬ 
mentable disease, the periodical ophthalmia of horses, I may be 
allowed to remark, en passant, that, from whatever causes it may 
arise, whether from hereditary predisposition or adventitious cir¬ 
cumstances, no matter what its predisposing or exciting causes, 
whenever it has been once set up in the system, it will run its 
course in spite of our best efforts. It is something like setting a 
large stone a rolling down a steep hill; it will never stop till it 
gets to the bottom : at least, it must be confessed that, hitherto, 
all our attempts to arrest its progress have proved unsuccessful. 
I purpose, on a future occasion, to give you such remarks as 
have occurred to me on this interesting subject. 
