Collection Manuscript/Mixed Material Image 1 of Item 14. Letter from Dato' Seri Pikrama Raja of Siak Indrapura to Colonel William Farquhar. Resident of Singapore. 18 Muharram 1235 (6 November 1819). Item 14. Letter from Dato' Seri Pikrama Raja of Siak Indrapura to Colonel William Farquhar. Resident of Singapore. 18 Muharram 1235 (6 November 1819).