Friendly reminder: if you own a Patek Philippe Caliber 89, don't forget to get the Easter program wheel swapped out before you miss next year's egg hunt. If not, you can grab one at the popular online auction site.
"Let us suppose that Easter is to be kept (as is at least implied by the British Act of Parliament regulating its date) on the Sunday after the astronomical full moon, and that this full moon, as sometimes happens, occurs just before midnight on Saturday evening in the western districts of London or New York. The full moon will therefore happen a little after midnight in the eastern districts, so that Easter, if regulated strictly by the paschal full moon, must be kept on one Sunday in the western and on the following Sunday in the eastern districts of the same city. Lest it be thought that this is carrying astronomical exactness to extremes, we may say that, if Easter were dependent on the astronomical moons, the feast could not always be kept on the same Sunday in England and America. Seeing, therefore, that astronomical accuracy must at some point give way to convenience and that an arbitrary decision on this point is necessary, the Church has drawn up a lunar calendar which maintains as close a relation with the astronomical moons as is practicable, and has decreed that Easter is to be kept on the Sunday after the fourteenth day of the paschal moon as indicated by this calendar."
In other words, if you want to see what science brutalized into the service of religion looks like, read on:
"In the year 1800, both the Lunar and Solar Equations (i.e. the addition and subtraction of 1) occur and no change of Epacts takes place. In 1900 the Solar Equation occurs and we must again subtract 1 from the Epacts. No change takes place in 2000 or in 2100, the former being a leap year and the latter having both equations. In 2200 and in 2300, we must again subtract 1, while in 2400, in which the Lunar Equation occurs and is not neutralized as usual by the Solar Equation, we add 1 to all the Epacts. The accompanying table [below] gives the Epact of every year from 1 B.C. to A.D. 3099.
Examples. (1) To find the Epact of the year 3097. Golden Number is 1, since (3097+1)÷19 = 163, with 1 as remainder. Epact corresponding to Golden Number 1 after 2900 is XXV; therefore the Epact of 3097 is XXV."
Long division and roman numerals, ladies and gentlemen.
That's damn beautiful, actually.
Incidentally, those sotheby's auction catalogues are spectacular, particularly the "noteworthy timepieces" ones. I own three of them; they're generally available on that other auction site for pennies on the dollar.