Collection Manuscript/Mixed Material Image 1 of Item 25. Letter from Sultan Syed al-Sharif Abdul Jalil almarhum Saifuddin the Yang DiPertuan Besar of Siak Indrapura to Colonel William Farquhar. Resident of Singapore. 20 Jamadilakhir 1236 (24 March 1821). Item 25. Letter from Sultan Syed al-Sharif Abdul Jalil almarhum Saifuddin the Yang DiPertuan Besar of Siak Indrapura to Colonel William Farquhar. Resident of Singapore. 20 Jamadilakhir 1236 (24 March 1821).