MEMOIR EXPLANATORY OF A NEW PERPBTUAX CALENDAR. 11! 



in two of the item?, equations ol)taincd at a single inspection, and, in three other item;-. 

 t/ic i If. It is for others, however, to decide, (and I should most cheerfully submit 



the question to the two above-named eminent living authorities, on whom I have relied,) 

 whether the Tablet, which I now present to the Society as a new "method" professing 

 only to combine very condensed tables with plain rules, may not possess a sufficient. degr< e 

 ui' practical utility to deserve publication. 



Intent upon rendering the Tablet useful in calculations relating principally to the New 

 Style,! should not have thought of embracing in it the ancient Church Calendar, now 

 gone into disuse in almost every part of the Christian world, except the empire of Russia, 

 had I not met with the "very simple Table" given by Mr. De Morgan, at page 32, and 

 which he says " will supply the place of all rules as soon as the Golden Number and Domi- 

 nical Letter arc known." \<>\\, -uncc it has been steadily my aim to eliminate both those 

 portions of the scaffolding of the Calendar, my work seemed incomplete unless I could 

 still dispense with them, and could devise some other means, at least as easy in practice 

 as the ten rules placed by Mr. De Morgan on the subsequent page, for determining the 

 Old Style Easter. 



I sought in vain for a copy of Clavius in the public libraries of the United States,* bur 

 was fortunate enough to find, in the Library of this Society, "The Art of Verifying 

 Dates," (I/Art de verifier les dates, troisiemc edition, par un rcligieux Benedictin de la 

 congregation de St. Maur, Tome premier, a Paris, 1783,) whose very extensive Tables 

 ted greatly the accomplishment of my object. The "Chronological Table." and the 

 •• Perpetual Lunar Calendar," both clearly exhibit the same constant concurrence between 

 the Paschal 11th of the Moon, and the place of the year in the cycle of 19, which is men- 

 tioned by Mr. Dc Morgan, and shown in his Table. We have therefore only to translate 

 into their corresponding Epacts, the several Golden Numbers, in the order in which they 

 there stand, and we shall obtain a scries of 19 Julian Epacts, descending while the days 

 of the month rise, as we before witnessed in the case of the Gregorian Calendar; with this 

 difference m the exposition, that blanks arc left at each of the ten places between the 21st 

 of March and the l v 'th of April, where there is no golden number, and where there can 

 o Epact, -nice the numbers wanting to complete a regular series (viz., 13, 10, 8, 5, 2 

 30, 27, 24, 21 and L9, as well as 16,) had no existence as Epacts in the Ancient Calendai 

 The Epact 29, forms a case by itself, on account of the peculiar interval of 12 between it 

 the succeeding Epact 11. In the Reformed Calendar the interval of 12 always precedes 

 the Epact, belonging to every year which is a multiple of 19. Rut if the Julian XXIX 

 he treated like the Gregorian 0, or XXX., and be made to change places with 30, i 

 ceases to appear anomalous. 



Compare the following columns with tho^c at page 117 of this memoir. The leading 

 Epact there was 23, and is here 15. 



There is one, I have since learned, in the Library of Harvard University, at Cambridge, Massachusetts. 



