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Art. VII . — Account of a singular Affection of Vision. By 
James Russell, Esq. F.R.S. E. and Professor of Clinical 
Surgery in the University of Edinburgh. Contained in a 
Letter to Dr Brewster. 
As I know that you take a deep interest in every curious fadt 
connected with optics, I use the freedom to send you an account 
of a singular affection of* vision which occurred to me some years 
ago. 
A gentleman came to town for a consultation, on account 
of a severe complaint in his stomach. Previously to the com- 
mencement of this complaint, he saw equally well with both 
eyes, and the focal distance of distinct vision was the same in 
each of them. This distance, however, had now undergone a 
change in both eyes; and, what is a remarkable circumstance, 
the change in the two eyes was in opposite directions, the dis- 
tance in the one eye having become longer, and in the other 
shorter, than the original focal distance. But while the two 
eyes no longer corresponded in their limits of distinct vision, 
each of them still retained the power of adapting itself to varia- 
tions in the distance of external objects, so far as its limits of 
distinct vision admitted. The pupils retained their natural con- 
tractility to the stimulus of light. The cornea and the different 
humours possessed perfect transparency; and the most care- 
ful examination did not discover the slightest appearance of dis- 
ease in any part of the eye. 
The gentleman referred the origin of this affection of vision 
to the disordered state of his stomach, and I saw no reason to 
entertain the smallest doubt with regard to the justness of his 
conclusion. The eyes readily sympathise with any morbid ir- 
ritation of the stomach, though it certainly w^ould not have been 
expected, that one kind of irritation proceeding from the same 
source, should have produced such dissimilar effects in the two 
eyes. The gentleman left town before the complaint in his sto- 
mach was removed, which prevented us from verifying our 
opinion with regard to the dependence of the affection of his 
eyesight upon the state of his stomach by following the result 
of the case. 
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