2c violet on white 'Lion' internal postal stationery card (H&G 1, Paraguay Postal Stationery Catalogue #PC1) datelined 'Tacuari 2/5 83' on reverse posted on the railway with boxed 'VIA FERREO PARAGUAY' marking in black dated 2 MAY 1883 alongside. Addressed to 'Sn Jago Scherer, Colonia Sn Bernardino, EStac. Aregua' with ASUNCION transit cds dated 3 MAY also on front. A very fine correct use of this card being mailed internally and also a very early example of a Paraguayan Railroad marking on cover. In the 'Handbook of Paraguay' Hahn records five known used examples of this card all of which were addressed outside of Paraguay, although one other internal use is recorded. A great Paraguayan rarity and likely a unique use on the railway.