Collection Manuscript/Mixed Material Image 1 of Item 23. Letter from Engku Syed Muhammad Zain ibn almarhum al-Habib Abdul Rahman al-Qudsi of Riau to Colonel William Farquhar. Resident of Singapore. 9 Jamadilawal 1236 (12 February 1821). Item 23. Letter from Engku Syed Muhammad Zain ibn almarhum al-Habib Abdul Rahman al-Qudsi of Riau to Colonel William Farquhar. Resident of Singapore. 9 Jamadilawal 1236 (12 February 1821).