TRENDS IN USE N 9L

is true chiefly because of the role of students in the library
clientele.*

SUMMARY In summary, studies showing when people use
the public library indicate three definite curves of usage.
There has been a steady increase in the use of the library
during the past thirty years, and it is probable that with the
rising level of schooling in this country the long-term trend
will continue to be upward. It has been found that use of the
public library is closely associated with the business cycle,
that circulation increases in times of depression and declines in
years of prosperity. Public library circulation also follows a
seasonal curve, reaching peaks in March and October—No-
vember, troughs in December and during the summer months.
This fluctuation is related to the kind of book circulated,
that is, relatively more fiction than nonfiction is borrowed
during the summer months, when the schools are closed; and
the greater the circulation, the more nonfiction books are
circulated.

‘A labored attempt to explain this seasonal variation dealt with the effects of
climatic conditions upon mental activity, and specifically the effects of polar
infalls of air and the amount of ozone in the air (Huntington, 1945, p. 375).
“The facts . . . leave little doubt that, regardless of rain or shine, people’s
impulse to draw books from the library 1s subject to constant fluctuations
in harmony with the coming and going of the tropical and polar air masses
which bring storms . . . If the matter is looked at more broadly, daily li-
brary data . . . indicate that mental activity is dampened by the kind of
weather which normally prevails in tropical countries and stimulated by the
kind that prevails in fairly high latitudes except when they become exces-
sively cold.”