FIRST DAY OF USE OF THE CANCELLER 1878 (Jun 1) Envelope double letter rate sent to the “Editor of the Christian World” in London, via Brindisi and Aden bearing 1876 6a tied with first ten-bar canceller used at the Indian post office at Zanzibar along with the accompanying date-stamp, rare and very fine. This important cover was used on the first day of use of the canceller; one of only two known covers used on the first day. Provenance: Henry Heath