in ink on reverse. B.P.A. Certificate (1991). S.G. 13/26. Photo on front cover" /> unused 2½d. horizontal pair, the right stamp with Type 8 in blue, the left stamp with Type 4 in carmine; the left stamp with vertical crease otherwise fine unused with large part original gum. Both signed<I> "C.H. Mekeel"</I> in ink on reverse. B.P.A. Certificate (1991). S.G. 13/26. Photo on front cover | Christie's