373rd Heinrich Köhler auction - Day 1

1869, Thomas B. Morton & Co. Letter Post, "FRANCO" handstamp seal in red adhering on large part of cover from Thessaloniki to Genova with two-line "SALONICH 31 AOUT" and red "D.A.a.L" handstamp alongside, reverse with SEMLIN Disinfection cachet and transit- and arrival marks, an attractive and very rare cover being one of two known examples of this issue used on cover, signed Sloane
Provenance:  The Julius Steindler Collection "Shipping Companies stamps" (Robson Lowe 1972)
                      depicted in  S. Ringstrom and H.E. Tester "The Private Ship Letter Stamps of the World - Part 2" page 90