Subject
- Trade disputes22
- Air transport21
- Astronomy, Arab21
- Couriers21
- Death21
- Diaries21
- Foreign affairs21
- General Treaty with the Arab Tribes of the Persian Gulf (1820)21
- Intelligence21
- Lighthouses21
- Railway lines21
- Trade agreements21
- Transport infrastructure21
- Travel allowances21
- Banking20
- Medical personnel20
- Raids (Military science)20
- Revenue20
- Telegraphy20
- Travellers20