From the latest APS sales circuit to come my way, I picked up two more China cancels.
The left stamp is Hong Kong Scott 13 canceled with the "S1" obliterator at Shanghai (listed in the Scott Classic Specialized catalog as LSH13). However, it could be the "S2" obliterator used at Swatow.
The right stamp is Great Britain-Offices in China Scott 5. It's been canceled with an Amoy circular date stamp (most likely, type J).