49^ PHILOSOPHICAL TRANSACTIONS. ^ANNO l68i, 



able the 38th part every year backwards, or contrary to the months in the 

 garter, its revolution is completed in 38 years : and the 38th year current, or 

 the year of the period or cycle, is shown through another hole. The new 

 year and account may best begin with the vernal equinox ; or rather with the 

 day of the new moon happening near midnight about that time, as March 10, 

 l680. Once every century, or to one year in 100, add one day, viz. to the 

 first 50th year, or middle of the century, or rather to the first 70th year, be- 

 cause the first new moon, March 10, l680, happens a little after midnight, and 

 after the vernal equinox, and then to every 100th year following; which ad- 

 ditional day being omitted every 230th or 240th century, if any one shall re- 

 quire such great exactness, will balance the account for ever. 



The Egyptian hieroglyphic of the year, was a serpent curved into a circle of 

 ring, with the tail in its mouth; but the emblematical garter will be much more 

 proper for England, &c. and is so exactly fitted to the moon's motion, that one 

 day will not be lost or gained in millions of years. 



This Al-mon-ac measures time principally by the moon, but with a great and 

 near respect to the annual motion of the sun or earth. The unit or least mea- 

 sure is a day ; and the garter or luni-solar year will be at a medium, within 

 about a week, or a 50th part of the true solar year; that is so near, that the 

 difference will not be discerned by ordinary popular observation, and therefore 

 must needs answer the ends of husbandry, and other civil affairs, well enough 

 and come often near, and be sometimes very near ; and at certain periods they 

 balance each other, and have a kind of coincidence, or agreement, much better 

 then the sun's course has with the Julian account. 



The ancients generally computed their time by the moon, or by the lunar, 

 or luni-solar year, as some, particularly the eastern people do still ; which year 

 was made up of moons, or real months, to the number of 12, for the most 

 part, and some years 13. This appears from their calendars, &c. It is plain, 

 from 1 Sam. c. xx. v. 5, 18, 24, compared with v. 27, 34, that the days of 

 the Jewish month were the same with those of the moon : and the Greeks, 

 particularly the Athenians, according to the institution of their wise legislator 

 Solon, thus reckoned their time ; and so did the Romans also, till Julius Caesar 

 altered rather than mended the year. 



Among the Greeks there lived, in 3 not far distant ages, 3 famous astrono- 

 mers in their several times, Meton, Calippus, and Hipparchus; each of whom 

 still farther improved astronomy, and rectified the accounts of time. Hip- 

 parchus the last of them, flourished about 90 or 100 years before Julius Caesar 

 altered the year ; yet Caesar, or his astronomer Sosigenes followed Calippus in 

 framing the Julian year: for Calippus's period of 76 years consisted of 27,7^9 



