TIENTSIN: 1918 Prisoner of War printed envelope sent insured for 200R to P.O.W. at Berezovka (Siberia), franked on the reverse with 3c on 3k, 4c on 4k (2), 10c on 10k and 15c on 15k all tied by Tientsin 17.2.18 cds (T&S type 6), sent via the Japanese P.O.s at Tientsin and Changchun, with insured label on obverse, wax seals on reverse, attractive