375rd Heinrich Köhler auction - Day 1

1873, folded lettersheet from Buenos Aires endorsed "p. Gironde" to Genoa with octogonal "BUENOS-AYRES PAQ. FR. J. No. 1 11 JANV 73" and scarce boxed "F.*56" alongside, upon arrival charged "10" decimes thus postage due 1l. applied to reverse and tied by cds., a fine cover after the date that the internal postage became mandatory (1. July 1873)