Books, both in the reference section and in the main (circulating) collection, are shelved according to the Library of Congress Classification system. This list is a general guide to different subject areas and their corresponding call number letters, as well as where they are located in the Mudd Library. See the Library of Congress Classification Outline for even more specific subjects.

Call No. Letter & General Subject
Call No. Letters & Selected Specific Subjects
Location in the Mudd Library
A -- General Works   Fourth Floor
  AE general encyclopedias fourth floor map
  AY almanacs, directories  
B -- Philosophy/Religion   Third Floor
  B philosophy (general) third floor map
  BF psychology  
  BL-BX religion  
  BM Judaism  
  BP Islam  
  BR Christianity  
  BS Bible  
  BX denominations and sects  
C -- Auxiliary Sciences of History   Fourth Floor
  CB history of civilization fourth floor map
  CS genealogy  
  CT general biography  
D -- History (General and World)   Fourth Floor
  D world history fourth floor map
  DA Great Britain  
  DC France  
  DD-DX other countries and areas  
E -- History of the Americas   Fourth Floor
  E America, Pre-Columbian America, elements in the population,  United States history fourth floor map
F -- History of the Americas   Fourth Floor
  F United States local history, Canadian history, Latin America, South America fourth floor map
G -- Geography   Fourth Floor
  G geography (general) fourth floor map
  GB physical geography  
  GN anthropology  
  GR folklore  
  GV recreation  
H -- Social Sciences   Fourth Floor
  HA statistics fourth floor map
  HB-HJ economics  
  HM-HX sociology  
J -- Political Science   Fourth Floor
  JA-JC political science fourth floor map
  JF-JN political institutions and public administration  
  JS local government  
  JV colonies and colonization  
  JZ international relations  
K -- Law   Fourth Floor
  K law in general fourth floor map
  KB religious law in general  
  KD-KWX laws of individual countries  
  KZ law of nations  
L -- Education   Fourth Floor
  L education (general) fourth floor map
  LB theory and practice of education  
  LC special aspects of education  
  LD-LG individual institutions by location  
  LH college and school magazines and papers  
  LJ student fraternities and societies  
M -- Music and Books on Music    
  M scores media center, first floor
  ML literature third floor
  MT musical instruction, study third floor
N -- Fine Arts   Third Floor
  NA architecture third floor map
  NB sculpture  
  NC drawing, design  
  ND painting  
  NE-NX other arts  
P -- Language and Literature   Third Floor
  P philology and linguistics third floor map
  PA classical  
  PN literature  
  PQ Romance literature  
  PR English literature  
  PS American literature  

PT Germanic literature

  PZ juvenile literature  
Q -- Science   Third Floor
  QA mathematics third floor map
  QB astronomy  
  QC physics  
  QD chemistry  
  QE geology  
  QH natural history  
  QK botany  
  QL zoology  
  QM human anatomy  
  QP physiology  
  QR microbiology  
R -- Medicine   Third Floor
  R medicine (general) third floor map
  RA public aspects of medicine  
  RB-RZ branches of medicine  
S -- Agriculture   Third Floor
  S agriculture (general) third floor map
  SB-SD plant culture, forestry  
  SF animal culture  
  SH aquaculture, fisheries  
  SK hunting sports  
T -- Technology   Third Floor
  TA-TK engineering by category third floor map
  TL motor vehicles, aeronautics, astronautics  
  TR photography  
  TS arts and crafts, handicrafts  
  TX home economics  
U -- Military Service   Third Floor
  UA armies third floor map
  UB military administration  
  UG military engineering  
V -- Naval Service   Third Floor
  VA navies third floor map
  VB naval administration  
  VK navigation, merchant marine  
  VM naval architecture, shipbuilding  
Z -- Bibliography, Library Science, Information Resources   Fourth Floor
  Z books, writing, paleography, libraries, bibliography fourth floor map
  ZA information resources