cover 1916 (19 Sept.) Nyasaland 4d. registered envelope, with "N.F." 1d., to "Headman Mtumbuka" at Fort Johnson, cancelled with "F.P.O./1" c.d.s. (Drysdall type D1 -- the second recorded date of use) and with black on pink registration label (Setting B); 1916 (Nov.) similar envelope to Fort Johnston with ½d. pair and manuscript "FPO 1"; both a little soiled