332 Dr. Reuben on moving Blood-corpuscles within the Retina. 
almost unaltered.” The words which I have here italicized de- 
seribe exactly what is true in regard to the red tint of dilute 
blood, and of course of the single attenuated streams of blood in 
the capillaries. The experiment itself disproves the possibility 
of a real or effective opacity of the blood-discs for green or blue 
rays. In seeing a blush on the cheek of another person, the eye 
takes in at once the hue of tens of thousands of closely aggrega- 
ted capillaries; and here the intensifying effect of concentration 
is experienced. But in witnessing the movement of the bl 
in the retina itself, the field is as it were spread out, and near 
objects thrust apart; and the effect of each pencil so small as to 
pass through one corpuscle, or two or three in succession, is no- 
ted by itself; so that no intensifying of color by mere contiguity 
separated, and the effect of glistening, or no sensible effect, should 
then be anticipated. i 
ey 
SS See ae 
