The various notes in this folder by William Stirling were for the greater part concerning his ideas on art and appear to have been intended for the eventual writing of his autobiography. Stirling was Assistant Protector of Chinese in Singapore from 1921 to 1931, and his collection includes a considerable amount of information on Chinese secret societies. The items that Stirling studied were those that had been seized during police raids, during and after 1890 when the British colonial government declared these societies illegal. Secret societies in Singapore can be traced back to the Tiandihui (Heaven and Earth Society) in China, a sworn fraternity in China comprising men with the common aim of overthrowing the Qing dynasty. Splinter groups subsequently emerged among the main dialect groups who migrated to Singapore, and these secret societies subsequently evolved into crime syndicates that proved extremely problematic for the colonial administration.