Mr. S. Rowley on a New Theory of Vision. 



195 



as expanded by outward reference, and cutting at right angles the 

 optic axis of that eye at the point where it intersects the optic axis 

 of the other eye. 



Or, to change the form of statement, the entire impressions on 

 the retinae, before becoming objects of consciousness, are projected in 

 space upon surfaces bisecting each other (perpendicularly to the 

 plane of the axes) at an angle greater or less according to the dis- 

 tance — the component points of each impressionbeing simultaneously 

 referred outward in lines passing from them through a point a little 

 behind the centre of the crystalline lens, but, excepting the expan- 

 sion and the inversion resulting from the crossing in the eye of the 

 directions of outward reference, undergoing no change of relative 

 position — the distance between the planes passing at right angles to 

 the optic axis through any two of the successive concentric zones of 

 points which make up the retinal impression continuing the same. 



I do not mean here to assert that an outward projection actu- 

 ally takes place, but that the effect of such a projection produced 

 by an intermediate process of mind is presented to the consci- 

 ousnesss. 



On a suitable plane surface take two points, C, C (fig. 1), 



Fie. 1. 



2 T 4 - inches apart, and in a line bisecting at right angles one 



02 



