THE GREGORIAN REFORM. 



tlie 129th part of a day per annum. The departure accumulating 

 from year to year would amount to a whole day in 129 years, to 

 two whole days in 258 years, to three in 387 years, and so on. 



Now, although such a departure would not be perceptible during 

 the lives of a single generation, it must evidently become so after 

 some centuries. The equinox falling back towards the beginning 

 of the year at the rate of one day in 129 years, was in the fifteenth 

 century thus thrown back as much as eleven days. 



It is evident that the continuance of this from century to 

 century would have thrown the equinox back from day to day 

 until it, and consequently the seasons, would have successively 

 assumed every possible position in the year. 



VIII. THE GREGORIAN" REFORM. 



101. Although in a more civilised and enlightened age this 

 would have been a reason sufficiently urgent to undertake a 

 revision and correction of the calendar, we are indebted for the 

 reform which took place to other and different causes. 



102. It was the rule of the Church to celebrate the festival of 

 the Resurrection at a time not far removed from the 21st March, 

 which was taken to be the day of the equinox, depending how- 

 ever also upon conditions connected with the lunar phenomena 

 with which we are not at present concerned, but which we shall 

 explain fully on another occasion. If therefore the real equinox 

 were subject, as we have stated, to a gradual change, which would 

 throw it back from year to year, so that it would fall each 

 successive year earlier and earlier, while the festival of Easter, 

 still related to the 21st March, would necessarily be farther and 

 farther removed from the equinox, it must obviously happen 

 in the course of time that the festival would fall successively 

 in every season of the year, and indeed on every day of the year. 



The Roman ecclesiastical authorities of the day becoming pain- 

 fully aware of this, and sensible that no decree of pope or council 

 could accelerate the motion of the equinox for the future, or 

 carry it forward from the llth to the 21st March; to repair the 

 error of the past, resolved that since they could not bring the 

 equinox to the 21st March, they would bring the 21st March to 

 the equinox. 



103. This change, with the others necessary to prevent the 

 recurrence of a like discordance between the ecclesiastical year 

 and the seasons, took place in the latter part of the sixteenth 

 century, in the pontificate of Gregory XIII., from whom the 

 reformed calendar came to be called the Gregorian calendar. 



As at the epoch of the Julian reform, two errors were to be 

 corrected, those of the past and those of the future. The accu- 



169 



