s suggested by the present writer fifteen years
ago. Its reception and serious consideration by one of the first
mathematical physicists of the world seems a sufficient justification of
its suggestion then as a legitimate scientific hypothesis.

THE ADVERTISEMENT OF IDEAS

Writing is a device for the storage of ideas--the only device for this
purpose prior to the invention of the phonograph, and not now likely to be
generally superseded. A book consists of stored ideas; sometimes it is
like a box, from which the contents must be lifted slowly and with more or
less toil; sometimes like a storage battery where one only has to make the
right kind of contact to get a discharge. At any rate, if we want people
to use books or to use them more, or to use them better, or to use a
different kind from that which they now use, we must lose sight for a
moment of the material part of the book, which is only the box or the lead
and acid of the storage battery, and fix our attention on the stored
ideas, which are what everybody wants--everybody, that is, except those
who collect books as curiosities. The subject of this lecture is thus only
library advertising, about which we have heard a good deal of late, but we
shall try to confine its applications to this inner or ideal substance
which it is our special business as librarians to purvey. And first, in
considering the matter, it may be worth while to say a word about
advertising in general. Practically an advertisement is an announcement by
somebody who has something to distribute. Announcements of this kind may
be classified, it seems to me, as economic, uneconomic and illegitimate.

The most elementary form is that of the person who tells you where you can
get something that you want--a simple statement that someone is a barber
or an inn-keeper, or gives music lessons, or has shoes for sale. This may
be accompanied by an effort to show that the goods offered are of
specially good quality or have some feature that makes them particularly
desirable, either to consumers in general or to those of a certain class.
This is all surely economic, so long as nothing but the truth is told.
Next we have an effort not only to supply existing wants and to direct
them into some particular channel, but to create a new field, to make
people realize a lack previously not felt; in other words to make people
want something that they need. This may be done simply by exhibiting or
describing t