1870 (25. Oct.) BALLON MONTÉ: Small printed ”PAR BALLON MONTÉ” letter flown with Ballon Nr. 19 ”VAUBAN” from Gare du Nord, Paris to Haguenau, Bas Rhin which was occupied by the Prussian at that time, franked by 1867 Napoleon 20 C. blue tied by Paris numeral 26 in star of dots, 25. Oct. 70 despatch d/s alongside, and on the reverse with SWISS Neuchatel '3.XII.70' transit datestamp and GERMAN arrival cds ”HAGENAU I. ELSASS 11 12 70”. Letter with light stains/toning (ageing), opened for presentation, and stamp with short perfs at top as affixed slightly across the letter's top. With expert signature on bottom right. A VERY RARE BALLON MONTÉ LETTER VIA SWITZERLAND AND WITH GERMAN ARRIVAL DATESTAMP.