cover 1911 (June) blue envelope, registered to Edinburgh "via Siberia", bearing C.I.P. 20c. tied by a fine strike of the rare Patang non standard "I P O" cancellation with a second strike alongside and a readable strike of the Patang registered h.s. at left, an array of backstamps via the French P.O. in Peking. A delightful and important cover. Photo