VOL. XXIV.] PHILOSOPHICAL TRANSACTIONS. 251 



which may be called the church calendar, counting that day of the month for 

 the first of the moon, which has the golden number of the year collateral to it 

 in the first column of the said calendar. 2. And that these words, " next after 

 March 21," are meant inclusively, as if it had been said, next after the com- 

 mencement of March 2 I ; so that if the full moon happens on March 21, the 

 same must be the paschal full moon. 



Now, in order to prove that these observations are both right, and sufficient 

 for understanding the rule, I shall only suppose, that if they are necessary 

 and sufficient to reconcile the rule with the authentic table to find Easter, (from 

 which practice never varies) then are they right and sufficient. Which being 

 premised: 



1. I prove that the first observation is necessary to that end: because, if the 

 paschal full moon be any day before or after the 14th of the moon by the church 

 calendar, then the rule and the table will clash. For (1), if it be any day 

 before, then as often as the said 14th of the paschal moon is a Sunday, that 

 very day, at latest, must be Easter-day by the rule, as being a Sunday after the 

 full moon therein meant: whereas by the table and practice it is not till the 

 Sunday after that. Thus, Sunday, April 1, this year (1705) was the 14th day 

 of the moon by the church calendar, and therefore must have been Easter-day 

 or after, by the rule, if the full moon therein meant had been any day before 

 the said 14th of the moon; whereas Easter-day was April 8, by the table, and 

 was observed accordingly. And this obliges us not to understand the true full 

 moon, by the full moon in the rule, because that happens about 4 days before 

 the 14th of the moon by the church calendar. (2) If the full moon meant in 

 the rule, beany day after the 14th of the paschal moon by the church calendar, 

 then as often as the said I4th happens to be Saturday, and consequently the 

 full moon meant in the rule to be the Sunday following at soonest (that being 

 the very next day) that Sunday cannot be Easter-day by the rule; whereas by 

 the table and practice it is. Thus, Saturday, April 4, 1702, was the 14th day, 

 of the moon by the church calendar; and therefore if the full moon meant in 

 the rule were any day after that, it must have been on Sunday, April 5, at 

 soonest; consequently April 12 at soonest must have been Easter-day by the 

 rule; whereas April 5 was Easter-day by the table and practice: and this evinces 

 the mistake of those, who make the 15th day of the moon to be the full in 

 the sense of the rule ; as Dr. Wallis, Philos. Trans. 240, Mr. Wright, in his 

 Postscript to his Short View of Mr. Whiston's Chronology, &c. and the Intro- 

 ductio ad Chronologiam (reprinted at Oxford, A. D. 1704.) p. 37. 



2. I prove the second observation necessary to the same end ; because a full 

 moon in the sense of the rule, (viz. the 14th day of a moon by the church 



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