Gregorian Calendar.- Bettazzi (Giacomo) Epitome operis Paschalis...proferens in prooemio necessitatem emendandi correctionem Gregorianam..., half-title, title in red & black with engraved device, woodcut head- & tail-pieces and initials, 6 folding tables, 1733; Lettera... nella quale egli espone il suo sentimento intorno ad una dissertazione stampata in Roma col titolo De recta festivitate Paschae anno MDCCXXXIV celebranda, 8pp. title with woodcut ornament, woodcut head-piece and initial, light stains to final leaf, 1734, together 2 works in 1 vol., Florence, Bernardo Paperini § Manfredi (Eustachio) Elementi della Cronologia con diverse scritture appartenenti al Calendario Romano, title with engraved printer's device, Bologna, Lelio dalla Volpe, 1744, first editions, nineteenth-century half calf by Hatton of Manchester, rubbed, 4to (2)

⁂ Bettazzi tried to correct the errors in the Gregorian calendar without altering its substance so that Protestant churches, previously rejecting it as erroneous, could adopt it. However, Bettazzi's work provoked much polemic, and he wrote an apologia of his thesis in 1734 (the second item in the first volume).