T Geology. Geography
| T1 | General. Geophysics | |
| T3 | Physical geography | |
| T4 | Meteorology. Seasons. Climate | |
| T7 | Palaeontology |
Geography
| T10 | General and human geography | |
| T11 | Biogeography | |
| T12 | Environmental history | |
| T14 | Economic and commercial geography. Planning. regional development. Environmental science | |
| T16 | Migration. Movements of peoples. | |
| T20 | Guidebooks. Travellers’ handbooks |
Geography by countries
| T21 | Europe : general | |
| T22 | Great Britain | |
| T24 | London | |
| T29 | British Empire and Commonwealth | |
| T30 | France | |
| T32 | Central Europe | |
| T33 | Italy and Mediterranean | |
| T37 | Eastern Europe and Levant | |
| T40 | Asia | |
| T60 | N. America | |
| T70 | Central and South America | |
| T80 | Africa | |
| T81 | North Africa | |
| T82 | West Africa | |
| T83 | Central Africa | |
| T84 | East Africa | |
| T85 | Southern Africa |