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apparent direction of eyes in a portrait. 
If we examine with attention the eyes of a person opposite 
to us, looking horizontally within about twenty degrees on 
either side of us, we find that the most perceptible variation 
in the appearance of his eyes, in consequence of their lateral 
motion, is an increase and decrease of the white parts at the 
angles of each eye, dependent on their being turned to or 
from the nose. 
In the central position of an eye, the two portions of white 
are nearly equal. By this equality, we are able to decide that 
a person is looking neither to his right nor to his left, hut 
straight forward in the direction of his nose, as index of the 
general position of his face. 
If, on the contrary, he turn his eyes to one side, we are 
immediately made sensible of the change by a diminution of 
the white of the eye on that side to which they turn, and by 
this test alone we are able to estimate in what degree they 
deviate in direction from the face to which they belong. 
But their direction with reference to ourselves As perfectly dis- 
tinct from the former ; and in judging of this it seems pro- 
bable that, even in viewing real eyes, we are not guided by 
the eyes alone, but are unconsciously aided by the concurrent 
position of the entire face ; for in a portrait, the effect of this 
further condition admits of being proved by a distinct and 
decisive experiment. 
If a pair of eyes be drawn with correctness, looking at the 
spectator, at such moderate deviation from the general po- 
sition of the face as is usual in the best portraits, unless some 
touch be added to suggest the turn of face, the direction of 
the eyes seems vague, and so undetermined, that their direc- 
tion will not appear the same to all persons ; and to the same 
MDCCCXXIV. K k 
