e as one which has occurred in a
series of past events. The definite reference of a memory image to a
past series is sometimes spoken of as localization. The degree to which
a memory image is localized in the past differs greatly, however, in
different cases. Your recollection of some interesting personal event in
your past school history may be very definitely located as to time,
image after image reinstating themselves in memory in the order of their
actual occurrence. Such a similar series of events must have taken place
when, by means of handling a number of objects, you learned different
number and quantity relations or, by drawing certain figures, discovered
certain geometrical relations. At the present time, however, although
you remember clearly the general relations, you are utterly unable to
recall the more incidental facts connected with their original
presentation, or even localize the remembered knowledge at all
definitely in past time. Nothing, in fact, remains as a permanent
possession except the general, or scientific, truth involved in the
experience.

CLASSIFICATION OF MEMORIES

=A. Mechanical.=--The above facts would indicate that in many cases the
mind would find it more effective to omit from conscious recall what may
appear irrelevant in the original presentation, and fix attention upon
only the essential features. From this standpoint, two somewhat
different types of memory are to be found among individuals. With many
people, it seems as if a past experience must be revived in every
detail. If such a one sets out to report a simple experience, such as
seeing a policeman arrest a man on the street, he must bring in every
collateral circumstance, no matter how foreign to the incident. He must
mention, for example, that he himself had on a new straw hat, that his
companion was smoking a cigar, was accompanied by his dog, and was
talking about his crops, at the time they observed the arrest. This type
is known as a mechanical memory. Very good examples of such will be seen
in the persons of "Farmer Philip" in Tennyson's _Brook_ and the
"landlady" in Shakespeare's _King Henry IV_.

=B. Logical.=--In another type of memory, the mind does not thus
associate into the memory experience every little detail of the original
experience. The outstanding facts, especially those which are bound by
some logical sequence, are the only ones which enter into permanent
association. Such a type of mind, therefore,