February 18, 1867. 
The PresipENT (H. W. Cookson, D.D., Master of St Peter's 
College) in the Chair. 
The following new Fellow was elected: 
Rey. JosepH CastTLey, M.A., Pembroke College. 
On the continued change in an Eye affected with a 
peculiar malformation. By Guorce Bippet Airy, 
M.A., LL.D., D.C.L.; formerly Fellow of Trinity 
College; and late Plumian Professor of Astronomy 
and Experimental Philosophy in the University of 
Cambridge; Astronomer Royal. 
On two occasions, of which the first occurred forty-one years 
ago, I have communicated to the Cambridge Philosophical 
Society the description and numerical elements of a malforma- 
tion affecting my left eye. In the first communication, dated 
1825, February 5, I gave as the characteristic of the mal- 
formation this result of experiment; that, on viewing a very 
small luminous point, formed by the light passing through 
an extremely minute hole in a blackened card, the luminous 
point, at one distance, presented to the malformed eye the 
appearance of a sharply defined line nearly horizontal, and, at 
a greater distance, presented the appearance of a sharply defined 
line at right angles to the former line, and therefore nearly ver- 
tical. And, as numerical elements, I gave the measures of the 
5—2 
