Answered By: Emily Pearson
Last Updated: Aug 31, 2021     Views: 82


Penrose Library organizes books using Library of Congress call numbers. Call numbers are made up of a combination of letters and numbers that represent specific subjects. Library of Congress uses the letters of the alphabet to represent broad subject categories and subdivisions. For example, J represents Political Science and R represents Medicine.

When you find a book you're interested in the catalog, you'll see a location and call number listed. Using The Empathy Exams by Leslie Jamison as an example, the catalog lists the call number as PS3610.A485 E47 2014.  

To understand the call number for this book, here's how to break it down:

P represents the broad subject of Language & Literatures. Books are shelved first by this section of the call number, in alphabetical order. 

PS gathers books representing American Literature.

3610 represents a further refinement of the subject.  In this case it stands for books published after 2000 and is treated as a whole number.  

.A485 represents the author's name.  Because there are so many American authors, this number may get quite complex.  This is a decimal number (not a whole number.)  For example, .E485 will come after .E4 and before .E5.

 E47, the final element, represents the title of the book.  This is typically a whole number.

2014 is the year the book was published.  Dates do not always appear as part of a call number.

On the Penrose Library shelves, The Empathy Exams is surrounded by books with these call numbers:

PS3610.A458 A68 2012

PS3610.A485 E47 2014

PS3610.A55 S77 2007

To help you find where a book is located, call number ranges appear on the end panel of each row of shelves.  PS3610.A485 E47 2014 will be in the range of shelving that is labeled PS3573.A4795 M 29 1994 - PS3612.I877 S43 2006.

The catalog provides the ability to text message the call number to a personal cell phone.  Standard text-messaging fees may apply.

Books are divided between all four floors of the library:

A-BQ: 4th floor
BR-NZ: 3rd floor
P-PZ: 2nd floor
Q-ZA: 1st floor

Locations of specific collections, like DVDs and the Eells Northwest Collection, can be found here.