this reason that the witticisms, sayings, and
scattered pieces of information, which we pick up here and there, are
so soon forgotten. There is no way of bringing about their frequent
reproduction when they are so disconnected, for the reproduction of
ideas is largely governed by the law of association. One idea reminds
us of another closely related to it; this of another, etc., till a long
series is produced. They are bound together like the links of a chain,
and one draws another along with it just as one link of a chain drags
another after it. A mental image that is not one of such a series
cannot hope to come often to consciousness; it must as a rule sink into
oblivion, because the usual means of calling it forth are wanting."
(F. McMurry, "Relation of natural science to other studies.")

We are not conscious of the constant dependence of our thinking and
conversation upon the _law of association_. It may be frequently
observed in the familiar conversation of several persons in a company.
The simple mention of a topic will often suggest half a dozen things
that different ones are prompted to say about it, and may even give
direction to the conversation for a whole evening. Now if it is true
that ideas are more easily remembered and used if associated, let us
_increase the associations_. Why not bind all the studies and ideas of
a child as closely together as possible by natural lines of
association? Why not select for reading lessons those materials which
will throw added light upon contemporaneous lessons in history, botany,
and geography? Then if the reading lesson presents in detail the
battle of _King's Mountain_, take the pains to refer to this part of
the history and put this lesson into connection with historical facts
elsewhere learned. If a reading lesson gives a full description of the
_palm tree_, its growth and use, what better setting could this
knowledge find than in the geography of Northern Africa and the West
Indies?

The numerous associations into which ideas enter, without producing
confusion make them more _serviceable_ for every kind of use. "It is
only by associating thoughts closely that a person comes to possess
them securely and have command over them. One's reproduction of ideas
is then rapid enough to enable him to comprehend a situation quickly,
and form a judgment with some safety, his knowledge is all present and
ready for use; while on the other hand, one whose related th