Collection Manuscript/Mixed Material Image 1 of Item 42 1/2. Letter from the Pengiran of Siak to Colonel William Farquhar. Resident of Singapore. 23 Rabiulakhir 1238 (7 January 1823). Item 42 1/2. Letter from the Pengiran of Siak to Colonel William Farquhar. Resident of Singapore. 23 Rabiulakhir 1238 (7 January 1823).