ALMANACK, a book, or table, containing a calendar of days and months, the rising and setting of the sun, the age of the moon, the eclipses of both luminaries, &c.—Authors are divided with regard to the etymology of the word; some deriving it from the Arabic particle al, and manach, to count; some from almanah, new-years gifts, because the Arabian astrologers used at the beginning of the year to make presents of
of their ephemerides; and others, from the Teutonic alman-acht, observations on all the months. Mr Johnson derives it from the Arabic particle al, and the Greek mes, a month. But the most simple etymology appears from the common spelling; the word being composed of two Arabic ones, Al Manack, which signify the Diary. All the classes of Arabs are commonly much given to the study of astronomy and astrology; to both which a pastoral life, and a sort of husbandry, not only incline them, but give them time and leisure to apply themselves to them. They neither sow, reap, plant, travel, buy or sell, or undertake any expedition or matter, without previously consulting the stars, or, in other words, their almanacks, or some of the makers of them. From these people, by their vicinity to Europe, this art, no less useful in one sense than stupid and ridiculous in another, hath passed over hither: and those astronomical compositions have still every where not only retained their old Arabic name; but were, like theirs, for a long while, and still are among many European nations, interspersed with a great number of astrological rules for planting, sowing, bleeding, purging, &c. down to the cutting of the hair and paring of the nails.—Regiomontanus appears to have been the first in Europe, however, who reduced almanacks into their present form and method, gave the characters of each year and month, foretold the eclipses and other phases, calculated the motions of the planets, &c. His first almanack was published in 1474.
Almanacks differ from one another, chiefly, in containing some more, others fewer, particulars.
The essential part is the calendar of months and days, with the risings and settings of the sun, age of the moon, &c. To these are added various parerga, astronomical, meteorological, chronological, political, rural, &c. as calculations and accounts of eclipses, solar ingresses, prognostics of the weather, tables of the tides, terms, &c. lists of posts, offices, dignities, public institutions, with many other articles political as well as local, and differing in different countries.—A great variety are annually published in Britain; some for binding, which may be denominated book-almanacks; others in loose papers, called sheet-almanacks.
The modern almanack answers to the Fasti of the ancient Romans. See FASTI.
Construction of ALMANACKS. The first thing to be done is, to compute the sun's and moon's place for each day of the year, or it may be taken from some ephemerides and entered into the almanack; next, find the dominical letter, and, by means thereof, distribute the calendar into weeks; then, having computed the time of easter, by it fix the other moveable feasts; adding the immovable ones, with the names of the martyrs, the rising and setting of each luminary, the length of day and night, the aspects of the planets, the phases of the moon, and the sun's entrance into the cardinal points of the ecliptic, i. e. the two equinoxes and solstices*. By the help of good astronomical tables or ephemerides, the construction of almanacks is extremely easy.