LATE USE 1854 DIE I 1D PL.193(RK)S.C.16(SG17) ON 1857 MOURNING ENVELOPE. 1857 envelope used locally in London bearing Die 1 plate 193 S.C.16 (SG17) lettered RK tied London District '74' duplex AP 10 57. LATE USAGE OF THIS ISSUE SELDOM SEEN. (Ref 20014).