on the Affections and Properties of Light. 357 
iight is reflected, some rays are constantly disposed into larger 
images than others are, that is, into images more distended in 
length, though of the same breadth. The fourth experiment 
shews, that the same takes place when light is inflected and 
deflected; and the two last shew that the same happens when the 
rays are refracted in a way similar or analogous to that in which 
the other images were produced by reflexion and flexion. 
We are now to shew, that this difference of size is not owing 
to the different reflexibilities and flexibilities of the rays. In 
order to this we shall both demonstrate, and then prove by ex- 
perience, “ that inflexion and deflexion do not decompound 
“ heterogeneous rays, whose direction is such, that they fall on 
“ the bending body/’ In fig. 2. let AB be the body; GH,E F, 
C D, the limits of its spheres of deflexion, inflexion, and re- 
flexion, respectively ; and let I P be a white ray of direct light 
entering at P the sphere of deflexion : through P draw L K at 
right angles to G H ; IP will be separated into P R red, and PV 
violet, and the five other colorific rays according to their de- 
flexibilities ; at R and V draw the perpendiculars ST and 
Q O ; then the alternate angles P R T, R P L ; and P V Q, 
VP L are equal each to each. But T R P and Q V P are the 
angles of incidence, at which the red and violet enter the sphere 
of inflexion ; and R P L, V P L are the angles of deflexion of 
the red and the violet ; therefore the difference of the two latter, 
that is R P V, is likewise the difference of the two former. 
Suppose this difference equal to nothing; or that PV and PR 
are parallel ; then /- R S the angle of the red’s inflexion will be 
less than vV O the angle of the violet’s inflexion, by the angle 
RPV: (when not evanescent) add R P V to r R S ; then rRS 
will be equal to z>VO : that is, the divergence will be destroyed, 
3 A 2 
