dividual experiences of ancestors; of this I do not here
speak.

All sensations leave traces behind in the brain; weak ones leave such as
are easy to be obliterated by others; strong ones, traces more enduring.

At the beginning of life it seems to be the department of taste (sweet)
and of smell (smell of milk) in which memory is first operative (Vol. I,
p. 124). Then comes the sense of touch (in nursing). Next in order the
sense of sight chiefly asserts itself as an early promoter of memory.
Hearing does not come till later.

If the infant, in the period from three to six months of age, is brought
into a room he has not before seen, his expression changes; he is
astonished. The new sensations of light, the different apportionment of
light and dark, arouse his attention; and when he comes back to his
former surroundings he is not astonished. These have lost the _stimulus
of novelty_--i. e., a certain _reminiscence_ of them has remained with
the child, they have _impressed_ themselves upon him.

Long before the thirtieth week, healthy children distinguish human faces
definitely from one another; first, the faces of the mother and the
nurse, then the face of the father, seen less often; and all three of
these from every strange face. Probably faces are the first thing
frequently perceived clearly by the eye. It has been found surprising
that infants so much earlier recognize human faces and forms, and follow
them with the gaze, than they do other objects. But human forms and
faces, being large, moving objects, awaken interest more than other
objects do; and on account of the manner of their movements, and because
they are the source from which the voice issues, are essentially
different from other objects in the field of vision. "In these movements
they are also characterized as a coherent whole, and the face, as a
whitish-reddish patch with the two sparkling eyes, is always a part of
this image that will be easy to recognize, even for one who has seen it
but a few times" (Helmholtz).

Hence the memory for faces is established earlier than that for other
visual impressions, and with this the ability to recognize members of
the family. A little girl, who does not speak at all, looks at pictures
with considerable interest in the seventh month, "and points meantime
with her little forefinger to the heads of the human figures" (Frau von
Struempell).

My child in the second month could already localize the face and voice