A very fine 30c Vermilion SG57 cancelled by a NEUCHATEL CDS ‘NEUCHATEL/6/AVR 67/6 S’ on a lettersheet to Mulhouse. Red MULHOUSE CDS ‘7/AVRIL/67’ and black boxed ‘PD’ cancel on front. Back-stamped with a BASEL CDS. With contents. letter in French dated 6th April 1867.