ON CATARACT. 
495 
necessity for every purchaser to have his horses examined imme- 
diately after purchase, and which ought always to be done inde- 
pendent of this point. 
I should be glad if Mr. Davies or Mr. Gwynn, veterinary sur- 
geons of Welchpool, would slightly try to ascertain a little more 
respecting this case, as it is in their neighbourhood, and commur 
nicate it either to you or to me, as I am as desirous as any one 
to come at the truth of similar cases. 
EXAMINATION OF AN EYE 
AFTER HAVING HAD SEVERAL ATTACKS OF INFLAMMATION, 
AND PREVIOUS TO THE FORMATION OF CATARACT. 
By the same. 
On the 13th May, 1836, Mr. Gretton, surgeon, of this town, 
had a blood mare of his taken suddenly ill of acute peritoneal in- 
flammation of the bowels, in consequence of having drank a 
bucket-full of cold water, and of which she died on the 15th. 
She had had three or four severe attacks of ophthalmia, with great 
effusion, in one of her eyes within the last eight or nine months, 
and which had regained, as much as is usual, its transparency, 
but, of course, leaving it after each attack more dull and disco- 
loured. Examination of the eyes took place soon after she died. 
The Unsound Eye. — The vitreous humour had not that beau- 
tifully white glassy appearance that it has in its sound state, 
but was of a very pale amber colour, having a slight tinge of 
green in it. The lens and capsule were, I may say, as near as 
possible of a natural colour and transparency ; but they certainly 
had the same lighter amber tinge as the vitreous humour. 
The Pigmentum Nigrum. — The under surface was highly in- 
flamed ; for on scraping the anterior surface off, it presented a 
scarlet appearance, evidently referrible to an immense number 
of small vessels : on cutting them across they evidently emptied 
themselves, as the redness in a great measure vanished. It was 
so evident, that after forcing the vitreous humour out, the parts 
were of a dark red colour when seen through the anterior coat of 
the pigmentum nigrum. This redness was not situated on or 
under any part that is called tapetum lucidum. 
Optic Nerve. — This was decidedly harder to cut through than 
that of the other eye, and was more dense in its texture. 
The sound Eye. — I examined this eye very particularly, and 
contrasted it with the other, which was very different from it. It 
was quite sound. There was not the least inflammation under 
the pigmentum nigrum. 
