The half-round franco cancel on the 10 cents 1864
From around May 1866 the so-called half-round franco cancel was introduced at the main post offices of the Netherlands Indies. The cancel assumed a double-function as both obliterator and date cancel. The half-round cancels from 51 different towns are known.
The sub-post offices continued to use the franco-in-box cancel for the cancellation of stamps. Often the associated or nearby main post office would subsequently place its half-round franco on the stamp, which is why we sometimes find stamps showing the combination of cancellations (see the display below).
Further details and catalogue can be found in P. Storm van Leeuwen, Poststempelcatalogus Nederlands-Indie 1864-1942, pp. 91-93.
A Chinese folded letter with bilingual address sent from Magelang 9 April to Samarang and received there 10 April ('rondstempel in red on the back). The distance between Magelang and Samarang in Central Java is 75 km. The front shows the Magelang half-round used as both obliterator and date cancel. This is a voluminous entire with full contents in Chinese and decorative features of private chops and printed floral patterns on back.
Makassar (Sulawesi Island)
Telok Betong (Sumatra)
Combinations half-round franco + franco
The franco cancel was applied at a sub-post office and the half-round at the associated or nearby main post office. As can be seen, it was not uncommon for the sub-offices to use blue instead of black ink for their franco cancellers. The main offices, by contrast, appear to have been consistent in using the black ink.
Soerabaija + franco (blue)
Banjoemaas (blue; part of year missing) + franco (blue)
Combination of two different half-round franco cancels
Once in a blue moon the discerning collector may come acrosss two different half-round handstamps on the same stamp. These are puzzling and I assume they come about when a letter is sent from a main post office to a destination abroad and transits via Batavia. All of these combinations that I know of have the Batavia cancels as one of the two. (I know of one letter sent 21 Feb. 1868 from Cheribon to Harleem in the Netherlands; the cover is franked with seven 10 cent stamps firstly struck with the half-round Cheribon 21/1 1868 and then with the Batavia half-round 26/2.)
Batavia + Palembang Batavia + Rembang