Prof. O. N. Rood on the Circulation in the Eye. 385 
Arr. XXXIV.—Additional observations on the Circulation in the 
iY. 
Eye; by OapEN N. Roop, of Troy University, N. Y. 
If however the light of a spirit-lamp with a salted wick, be 
concentrated on the eye by means of a convex lens, 3 inches in 
diameter, having a focal length of about 3 inches, the bright field 
soon resolves itself into a mass of small, round, densely packed 
moving bodies, which appear light on a dark ground 
_ This is seen with varying degrees of readiness by different 
persons: some perceiving it in a few seconds, others requiring a 
e _ protracted gaze of several minutes 
The moving bodies at first appear very closely packed together 
like fine mosaic-work, but as the view grows more distinct, their 
path ean be traced, and the conviction is forced on the min 
the observer, that they are moving at slow uniform rates, through 
narrow channels; the whole reminding one strongly of the cir- 
culation seen in the web of a frog’s foot, by a microscope slightly 
out of focus. 
he interposition of plates of yellow glass rather adds to the 
distinctness of this appearance. 
