and Experiments on Vision. 3B7 
nature in such cases, and that it might be imitated, in a young 
short-sighted person, by the application of Belladonna to his ' 
eyes. I have hitherto not been able to obtain permission to 
make the experiment on any young person, who is very short- 
sighted. Two gentlemen, however, who are somewhat short- 
sighted, have readily submitted to it ; one of them, Mr. 
Blundell, a diligent and ingenious student of medicine ; the 
other, Mr. Patrick, a well educated young surgeon in Lon- 
don. The first experiment was on Mr. Blundell, and the 
apparent result was, that the range of his accurate vision was 
considerably diminished at both ends, but not annihilated. Mr. 
Blundell, however, afterwards informed me, that he repeated 
the experiment with more care in the country, and found, that 
in one eye the nearest point of perfect vision was moved for- 
ward about two-thirds of the whole range, and in the other 
about one-third ; but that, with respect to both eyes, the 
most remote points of the ranges were unchanged. He added, 
that while one eye was under the influence of the Belladonna, 
the other became shorter-sighted than it had been before • 
but the difference was not so great, as to induce me to place 
entire confidence in the justness of his observation. I think it 
right to mention here, that from mistake I applied only two- 
thirds of the ordinary quantity of Belladonna to his eye, in the 
first experiment ; and that he probably, in consequence of my 
example, applied no more w hen he made the second ; as this 
might have been the reason, that during both experiments he 
retained, in part, the capacity of adapting his eyes to different 
distances. 
The experiment on Mr. Patrick was conducted by myself, 
after he had been frequently exercised in observing the extent 
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