PS 
commo 
field of view of the two eyes. In this case of course the ey 
J. LeConte on Binocular Vision. 161 
fatigue, I tried repeatedly after long rest but always the phe- 
nomena were precisely the same. In the diagram in which the 
Inclination of the lines was five degrees I observed, however, 
that a greater degree of convergence was necessary to bring 
the horizontals in coincidence than to bring the verticals into 
coincidence. The difference in the distance of the diagram in 
he two cases was about two inches and the difference in the 
distance of the point of sight was about one-half inch. I can- 
hot explain this except by supposing that the form of the 
ptic globe was changed by the excessive action of the 
muscles, 
across them. There is not the shadow of a doubt, therefore, 
¢ in my own case the eyes in convergence rotate slightly 
Fiber and that the amount of rotation increases with the 
s 
of the image was only 2 to 24 inches ; for the lines inclined 22 
“grees, the distance of the image was 4 inches; for lines 
‘nclined 14 degrees, the distance was 7 inches; and for 40 
tinutes, the distance was about 12 to 14 inches. I am able, 
by reat strain, to obliterate or nearly obliterate the n 
