1.Italy The Cavallini ("little horses") of Sardinia was an early government-operating mail service, notable for the introduction of prepaid stamped lettersheets in 1818. FIRST WORLD POSTAL STATIONERY. ganzsachen 1821. Post-Horn. Horse-riding. C-25. dark blue. Circular. Printed content. AMMINISTRAZIONE DELLE REGIE POSTE 18212.Italy. MANIFESTO CAMERALE, 1818. Torino. DELLA STAMPERIA REALE. Printed Notice 4pages.(one page is vacant)Three blue pictures of â€˜The Cavallini ("little horses")â€™ of Sardinia on 4th page.Very hard to find philatelic items.