QE - Geology 5,190
QA - Mathematics 3,087
QC - Physics 2,197
QH - Natural History and Biology 1,886
QL - Zoology 1,463
QK - Botany 990
QD - Chemistry 968
QP - Physiology 955
C - General History 931
Q - General Science 705
QB - Astronomy 515
QR - Microbiology 302
QM - Human Anatomy 200
HE - Transportation and Communications 47
TN - Mining Engineering and Metallurgy 46
E - United States History 28
D - General History 25
G - General Geography 25
F - General American History 14
L - General Education 6
PR - English Literature 6
PZ - Fiction 6
S - General Agriculture 6
TX - Home Economics 6
GB - Physical Geography 4
GN - Anthropology 4
GA - Mathematical Geography and Cartography 3
HS - Societies 3
RC - Internal Medicine 3
LB - Theory and Practice of Education 2
SB - Plant Culture 2
T - General Technology 2
TD - Environmental Technology 2
TP - Chemical Technology 2
VA - Navies 2
Z - Books and Writing 2
AE - Encyclopedias 1
BF - Psychology 1
GF - Human Ecology and Anthropogeography 1
HA - Statistics 1
HD - Industries, Land Use, Labor 1
HT - Communities, Classes, Races 1
J - General Legislature 1
JX - International Law 1
LC - Social Aspects of Education 1
M - Music 1
PE - English Languages 1
PS - American Literature 1
RM - Therapeutics and Pharmacology 1
SD - Forestry 1
SH - Aquaculture, Fisheries, Angling 1
SK - Hunting Sports 1
TA - General and Civil Engineering 1
TC - Hydraulic and Ocean Engineering 1
TK - Electrical and Nuclear Engineering 1
UC - Maintenance and Transportation 1