Medicine, the City and China.
D002681:China; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D007194:India; D008131:London; D009892:Opium / Q000266:history* / Q000600:supply & distribution; D004364:Pharmaceutical Preparations / Q000266:history* / Q000600:supply & distribution; D010946:Plants, Medicinal; D013662:Tea
D004364:Pharmaceutical Preparations; D013662:Tea; D009892:Opium