ccupy equal spaces, but those
that are most important to the child extend more widely than the rest.
There are many varieties as to the topmost month; it is by no means
always January.

The Forms of the letters of the alphabet, when imaged, as they
sometimes are, in that way, are equally easy to be accounted for,
therefore the ordinary Number-Form is the oldest of all, and
consequently the most interesting. I suppose that it first came into
existence when the child was learning to count, and was used by him
as a natural mnemonic diagram, to which he referred the spoken words
"one," "two," "three," etc. Also, that as soon as he began to read,
the visual symbol figures supplanted their verbal sounds, and
permanently established themselves on the Form. It therefore existed
at an earlier date than that at which the child began to learn to
read; it represents his mental processes at a time of which no other
record remains; it persists in vigorous activity, and offers itself
freely to our examination.

The teachers of many schools and colleges, some in America, have
kindly questioned their pupils for me; the results are given in the
two first columns of Plate I. It appears that the proportion of
young people who see numerals in Forms is greater than that of adults.
But for the most part their Forms are neither well defined nor
complicated. I conclude that when they are too faint to be of
service they are gradually neglected, and become wholly forgotten;
while if they are vivid and useful, they increase in vividness and
definition by the effect of habitual use. Hence, in adults, the two
classes of seers and non-seers are rather sharply defined, the
connecting link of intermediate cases which is observable in
childhood having disappeared.

These Forms are the most remarkable existing instances of what is
called "topical" memory, the essence of which appears to lie in the
establishment of a more exact system of division of labour in the
different parts of the brain, than is usually carried on. Topical
aids to memory are of the greatest service to many persons, and
teachers of mnemonics make large use of them, as by advising a
speaker to mentally associate the corners, etc., of a room with the
chief divisions of the speech he is about to deliver. Those who feel
the advantage of these aids most strongly are the most likely to
cultivate the use of numerical forms. I have read many books on
mnemonics, and cannot doubt their uti