Gregory Xiii.

, the principal event in whose life is the reformation he introduced in the Roman calendar, was born at Bologna in 1502. His name before his promotion was Hugh Buoncompagno. He was brought up to the study of the civil and canon law, which he taught in his native city with uncommon reputation. He was afterwards appointed judge of the court of commerce at Bologna. From this city he removed to Rome, where, after various preferments, he was on the death of Pius V. in 1572, unanimously elected his successor, and at his consecration he took the name of Gregory XIII. His reformation of the calendar, was according to a method suggested by Lewis Lilio, a Calabrian astronomer, which after his death was presented to the pope by his brother. This method, which was immediately adopted in all catholic countries, but was rejected by the protestants and by the Greeks, was intended to reform the old or Julian year, established by Julius Caesar, which consisted of'365 days 6 hours, or 365 difys and a quarter, that is three years of 365 days each, and the fourth year of 366 days. But as the mean tropical year consists only of 365 days 5 hours 48 minutes 57 seconds, the former lost 11 minutes 3 seconds every year, which in the time of pope Gregory had amounted to 10 <lays, and who, by adding these 10 days, brought the account of time to its proper day again, and at the same time appointed that every century after, a day more should be added, thereby making the years of the complete centuries, viz. 1600, 1700, 1800, &c. to be common years of 365 days each, instead of leap-years of 366 days, which makes the mean Gregorian year equal to 365 days 5 hours 45 minutes 36 seconds. This computation was not introduced into the account of time in England, till 1752, when the Julian account had lost 11 days, and therefore the 3d of September, was in that year by act of parliament accounted the 14th, thereby restoring the 11 days which had thus been omitted.

In 1584 Gregory incurred the suspicion, although some think without foundation, of having encouraged the assas, smation of Elizabeth queen of England, by Parr, an Eng* lisn catholic, who was detected in a conspiracy against the queen’s life. This pope contributed greatly to correct and amend Gratian’s decretals, which he enriched with learned He died of a quinsey, in the eighty-fourth year of | Jbis age, and the 14th of his pontificate, in 1586. Several of his “Letters,” “Harangues,”&c. are said to be in existence. ¹