re not observed. Moreover, it is a fact
that the swinging pendulum of a clock is "seen" at the extreme
position of the swing on each side, and not in the intermediate space.
This is because the image is formed very quickly, twice in the space
where the bob of the pendulum is coming to the limit of its swing and
is again returning on its course. For the same reason, the
outstretched legs of the horse going up to their limit and at once
returning give in very quick succession, near their extreme limit, an
ascending and a descending phase which are not strictly but sensibly
alike, and so doubly impress the retina, and obtain for the legs
"attention" when in that extreme position. The choice of the attitude
depicted by Morot is explained by the fact that, as is shown by its
persistence through two successive pictures (figs. 2 and 3 of Pl. I),
this pose must produce a more continuous impression on the retina than
any other of the attitudes shown, since none of them endure through
two successive pictures.

The mental process of attention results in a certain duration or
memory of the mental condition which is a distinct thing from the
primary retinal impression, and leads to the ignoring or mental
obliteration of an instantaneous interval separating two phases of the
position of moving legs which have strongly "arrested the attention."
Hence, it seems that the most forward pose of the galloping horse's
front legs and the most backward pose of its hind legs--though far
from simultaneous, even in the slow changing retinal impressions--may
be mentally combined by "the arrest of attention," and that the artist
really ought to present his picture of the galloping horse with those
two poses combined (although as a matter of scientific truth they do
not occur simultaneously) in order that he may produce by his painted
piece of canvas, as nearly as he can, the mental result which we call
"seeing" a horse gallop. This combination of the front half of one
figure with the hinder half of another so as to give in each case the
extreme phase of extension of the legs I have made in Pl. I, fig. 12.

But there is, further, in all "seeing" before even a mental result of
_attention_ to the retinal picture is, as it were, "passed," admitted
and registered as "a thing seen," the further operation of rapid
criticism or _judgment_, brief though it be. We are always
unconsciously forming lightning-like judgments by the use of our eyes,
rejecting t