The famous group of the Pleiades is well known; but there is great difficulty in understanding Al-Sufi's description of the cluster. He says, "The 29th star (of Taurus) is the more northern of the anterior side of the Pleiades themselves, and the 30th is the southern of the same side; the 31st is the following vertex of the Pleiades, and is in the more narrow part. The 32nd is situated outside the northern side. Among these stars, the 32nd is of the 4th magnitude, the others of the 5th." Now, it is very difficult or impossible to identify these stars with the stars in the Pleiades as they are at present. The brightest of all, Alcyone (η Tauri), now about 3rd magnitude, does not seem to be mentioned at all by Al-Sufi! as he says distinctly that "the brightest star" (No 32 of Taurus) is "outside" the Pleiades "on the northern side." It seems impossible to suppose that Al-Sufi could have overlooked Alcyone had it the same brightness it has now. The 32nd star seems to have disappeared, or at least diminished greatly in brightness, since the days of Al-Sufi. More than four stars were, however, seen by Al-Sufi, for he adds, "It is true that the stars of the Pleiades must exceed the four mentioned above, but I limit myself to these four because they are very near each other and the largest [that is, the brightest]; this is why I have mentioned them, neglecting the others." A full examination of the whole question is given by Flammarion in his interesting work _Les Étoiles_ (pp. 289-307), and I must refer my readers to this investigation for further details. According to Brown, Simonides of Keos (B.C. 556-467) says, "Atlas was the sire of seven daughters with violet locks, who are called the heavenly _Peleiades_."[405] The name is by some supposed to be derived from the Greek πλειων, full. The Old Testament word _Kimah_ (Job ix. 9 and xxviii. 31) and Amos (v. 8) is derived from the Assyrian _Kimta_, a "family." Aratus describes the Pleiades in the following lines:-- "Near his[406] left thigh together sweep along The flock of Clusterers. Not a mighty span Holds all, and they themselves are dim to see, And seven paths aloft men say they take, Yet six alone are viewed by mortal eye. These seven are called by name Alkyonî Kelainî, Meropî and Steropî Taygetî, Elecktrî, Maia queen. They thus together small and faint roll on Yet notable at morn and eve through Zeus."[407]