Q. Why are the periodicals arranged by call number?
The call numbers are assigned to organize materials according to subject. By giving call numbers to the periodicals, journals and magazines that belong to the same discipline are shelved together to make it easier to browse and do research within a subject. A person who wants to access all of our print journals in, say, psychology, can find them all in one place instead of hunting through the alphabet to find the Journal of Psychology, Psychology, Social Psychology Today, etc. And that same researcher can also find publications on a topic that they may not have previously aware of by name because they are grouped together by subject. A list of call numbers broken down by subject is on the Library of Congress website here: https://www.loc.gov/catdir/cpso/lcco/