cover -- 1902 (4 July) "Maus" envelope, registered to Germany, bearing "C.I.P." 5c. (2) tied by bilingual c.d.s. and 10c. tied by large "R" in black, with Hong Kong 20c. on 30c. grey-green cancelled by a part strike of the type 2 "I.P.O." tieprint and Hong Kong registered c.d.s., attractive