1 Sgr. black on rose, left cut into, otherwise with wide margins with clear number cancellation "1159" on cover with single circle. POTSDAM 15. 12. and personal senderãs name "A. Humboldt" and even written receiver address to Berlin with delivery cancellation, fold traces, superb, signed Ebel, very scarce combination, Alexander from Humboldt dwelled and worked in the City lock from Potsdam and was from 1849 citizen of honour from Potsdam