http://blueskyglassworks.ca/2015/01/custom-glass/attachment/500/ Sarawak Post Office Cancellation
The double-ring SARAWAK POST OFFICE cancellation is the earliest known Sarawak cancellation with 1st February 1858 as the first recorded date of use. Proud (2003) indicates that the cancellation was used up until the 17th of January 1865 (see cover below).
Within this timeframe, prior to the opening of the Kuching P.O. in 1869, the Sarawak postal service came within the vast sphere of influence exercised by the Indian Post Office (Lowe, 1951). During this period, Indian adhesives (issue of 1855-60) have been recorded used in Sarawak.
According to W.R. Forrester-Wood (1957), the cancellation was initially used as a ‘despatch’ mark to indicate the country of origin of the letter and therefore does not, in general, employed to cancel the adhesives. It was customary at that time that the when sending a letter beyond Singapore that the East India stamps were to be franked onto the letter non-obliterated. The Sarawak post Office despatch mark was to be applied away from the adhesives which were not cancelled until they reach Singapore.
get link Example of Cover
source link Letter from the Bishop of Labuan & Sarawak to London, 1865
This magnificent cover is an example of India stamps used in Labuan/Sarawak in 1865 to London, England via Southampton. On lower left corner just under the Sarawak Post Office cancel, endorsed F.T. Labuan in writing to indicate that the letter is from Rev. Francis Thomas McDougall, Bishop of Labuan & Sarawak from 1855-1868.
As customary, the Sarawak Post Office cancel is applied away from the Indian adhesives and a date of 17/1/65 inserted (this being the latest recorded date of use of the handstamp). London / Paid MR 7 65 arrival cancel on face. The cover is franked with India 1856/64 4a black horizontal pair tied in transit by black «B/172» numeral handstamps of Singapore. Sold US$ 3,500.
Auctioner’s Note: Carried on the P&O S.S. Carnatic leaving Singapore Jan 21, 1865 arriving Galle (Ceylon) on January 27, transhipped to S. S. Bengal on February 1, arriving Suez on February 15. Overland to Alexandria and carried on the S. S. Syria arriving Southampton March 7, 1865.
Edward B. Proud (2003) The Postal History of British Borneo, 2nd Edition.
W.R. Forrester-Wood (1957) The Stamps and Postal History of Sarawak, 1st Edition.
Robson Lowe (1951) The Encyclopædia of British Empire Postage Stamps Volume III, The Empire in Asia, 1st Edition.
The Sarawak Journals (No. 1-50).