[Illustration: FIG. 34.--Declinations of Northern Stars from 250 A.D. to 2150 B.C.] Which of these stars, then, must we consider? Obviously those most conveniently situated for enabling the time to be estimated during the night, or those which could have been used as warning stars. [Illustration: FIG. 35.--Declinations of Southern Stars from 250 A.D. to 2150 B.C. α Ceti, α Aquarii, β Orionis, α Capricorni, α Canis Majoris, α Scorpii, α Columbæ, α Pisces Austr., η Argûs, α Centauri, α Argûs, α Crucis, α Gruis, and α Eridani.] The warning stars can be conveniently picked up by using a precessional globe. From it we gather that about 1900, 1400 and 800 B.C. they were as follows for the critical times of the May year, _i.e._ May, August, November, February:-- 1900 B.C. 1400 B.C. 800 B.C. May Castor rising Pleiades rising Pleiades rising N. 41° E. N. 77° E. N. 71° E. Antares setting Antares setting S. 75° W. S. 72° W. August Arcturus Arcturus rising Sirius rising circumpolar. N. 17° E. S. 63° E. With hill 3′ high:-- Rising. Date 2170 B.C. N. 11°15′ E. „ 2090 B.C. N. 14°18′ E. „ 1900 B.C. N. 18°44′ E. November Betelgeuse setting N. 87° W. February Capella rising Capella rising Capella rising N. 36° E. N. 28° E. N. 21° E. For the solstices, that is, June and December, the following stars might be used as warners:-- 1900 B.C. 1400 B.C. 800 B.C. Summer Solstice Betelgeuse rising Betelgeuse γ Geminorum N. 87° E. rising N. 90° E. rising Arcturus setting Arcturus setting N. 68° E. with hill 3′ high (late) N. 16° W. (“Alhena” N. 18° W. α Serpentis mag. 1·9.) setting N. 53° W. Winter Solstice Sheat rising (early) Castor α Capricorni N. 72° E. setting N. 37° W. rising Markab rising (late) Pollux S. 66° E. S. 89° E. setting N. 42° W. It is obvious that a star used all the year round for night work will warn the sunrise at some one of the yearly festivals. When the stars having the same declinations are considered from this point of view, the star actually used, and _therefore the date of its use_, may generally be gathered. I shall show subsequently that some of the stars in the above lists were actually observed in British as well as in Grecian temples.