WEEK. This well-known period of seven days, now universally adopted over the Christian and Mohammedan world, appears to be of Hebrew or Chaldwan origin. It has been commonly regarded as a memorial of the creation of the world, according to the Mosaic account, in that space of time ; but it is besides the most obvious and conve nient division of the lunar or natural month ; and it is also more nearly than any other short term would be, an aliquot part of the solar year of 365 days ; so that its commodiousness in these two ways would seem to have been sufficient to recommend its adoption.
Dion Cassius attributes the invention of the week to the Egyptians, from whom he seems to say it was borrowed in later times by the Greeks and other nations (' Hist. Rom.; xxxvii. 18, 19, and the note in Reiniar's edition). It is certain that the week was unknown to the Greeks of the classical ages, and also to the Romans, till it was gradu ally adopted, along with Christianity, under the later emperors.
The curious passage we have referred to in Dion Cassius is the sourco of all that is known as to the origin of the names that have been given to the days of the week. The Ptolemaic arrangement of the heavenly bodies, according to their distances from the earth, is in this order : Saturn, Jupiter, Mars, the Sun, Venus, Mercury, the Moon (Saturn being the moat distant); and it was a principle of the ancient astrology that these planets presided in this succession over the hours of the day. Upon this notion, if the first hour be assigned to Saturn, it will be found that the 25th (or first hour of the second day) will fall to the Sun ; the 49th (or first of the third day) to the Moon ; the 73rd (or first of the fourth day) to Mars; the 97th (or first of the fifth day) to Mercury; the 121st (or first of the sixth day) to Jupiter ; and the 145th (or first of the seventh day) to Venue. Dies Saturni (the day of Saturn), Dies Solis (the day of the Sun), &c., are accordingly the Latin designations that have been given to the days of the week ; and from these have been formed the modern names used in different countries either by literal translation (in the Italian, Spanish, French, and other languages of the Latin stock), or (in the Teutonic tongues) by the substitution, in some cases, for the classical god of the corresponding deity of northern paganism. Thus, the deity of the Old Saxons most resem
bling Mars, being held to be Tiw, or Tin, the day of Mars was called by them, after their conversion to Christianity, Tiwes daeg, whence our Tuesday (and probably also the modern German Dienstag); for a similar reason the day of Mercury received the name of Wodnes daeg (that is, Woden's day), whence our Wednesday (and the old German Odinstag, for which Islittwoche, " Mid-week," is now used) ; the day of Jupiter, Thunree daeg, or Thor's day (whence our Thursday, and the modern German Donnerstag); and the day of Venus, Frige daeg, or Frigres day (whence our Dion Cassius, however, further states that the planetary theory from which the denominations of the days of the week have thus been derived is itself founded upon the doctrine of musical intervals. A highly curious exposition of this idea has been given by the Abb6 Roussier, in a Memoir on the Music of the Ancients, printed in the Mdmoires do Trdvoux; for November and December, 1770, and August, 1771.
It is a remarkable fact that the week of seven days is not only a recognised space of time in the ancient Brahminical astronomy, but that the days (beginning with Soucravaram, "the day of Venus," or our Friday) are named in succession after the same planets or heavenly bodies as among the Greeks and Latins. Upon this subject see Bailly's ' Astronomie Indienne et Orientate," and various papers by Mr. Cole. brooke and others in the ' Asiatic Researches.' The subject of the week is also discussed by Bohlen, Das Alte Indien; ii. 214.