Cape of Good Hope 1862 Consignees Letter to UK, Rare

1862 CONSIGNEES MAIL: Entire written on the embossed stationery of MACKIE DUNN & Co PORT ELIZABETH, addressed to the Brewers in Scotland and forwarded without postal charges (effective for letters up to 6oz from 1854) to the office of their overseas correspondence. MACKIE & Co of London who applied their cachet and the GB 1d franking, onposting the letter for onward transmission. Exceptional example of this very scarce mail whereby charterers of ships could send their mail without charge. VF, rare.