Oct., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



circle containing a four-mycd star. These we know, 

 from actual inscriptions on some stones of the kinti, to 

 be the symbols of the patron deities oi the first two 

 months of the year ; the first month being- presided 

 over by the moon-god, the second by a pair of deities, 

 the " Heavenly Twins." 



There is a special significance in both these symbols. 

 The -Accadian and .Assyrian \-ears were luni-solar, the 

 months being actual lunations, and twelve months 

 constituting a normal year. But since twelve months 

 are eleven d.iys short of a solar year,' a thirteenth 

 month must be intercalate'd about e\ery third year, or 

 the beginning of the year will quickly travel backwards 

 amongst the seasons. The Mahomedan year, which 

 consists of twelve lunar months, does this, and its fasts 

 and feasts bear no relation to the seasons. But the 

 .\ccadians evidently wished their year to conform ;is 

 closely as possible to the solar year, and the method 

 which they eniploycd to secure this result was both 

 simple and efficient. The first new moon of the year 

 was recognised by the presence near it in the evening 

 sky of a bright star, unquestionably at one time the 

 star Capella. It might happen that on the first even- 

 ing, when the thin crescent was perceived, it would be 

 close to Capella, and the two objects would set to- 

 gether. Twelve lunar months later the new moon 

 would be observed again, but these twelve months 

 being eleven days short of ;i complete solar year the 

 moon would be some ii° less advanced in longitude 

 than it was on the former occasion. But since the 

 moon's daily motion in longitude is about 13", the 

 moon and Capella would set nearly together on the 

 following evening — the second evening of the month. 



Fig. 4.— Equatorial Constellation.s, near the Autumn Hquinox, 

 B.C. JfiX.";. Zenith of .N. l.at. 40 



.At the end of another twelve months it would not he 

 until the third evening of the month that Capella ;md 

 the moon set together, and in a fourth year it would 

 probably be on the fourth evening. But this, again, 

 would involve that the two objects would set together 

 on the first evening of the following month, which 



would, therefore, be the true first month of the year. 



In other words, the third ye.ir, that is to say, any year 

 indicated by the setting together of the moon and 



Capella on the third evening of the month, would be a 

 yt^ar thirteen months in Iciii^th ; ollur ve.ars would be of 

 twelve months. 



If Capella were observed setting with the moon at 

 the beginning ol the first month, would there be ;niy 

 bright star seen with il :il llic beginning of the second 

 month? There would be two— Caslor and Pollux — 

 which would serve, should the evenings ol llu' first 

 month have been cloudy, to luniish just the same 



r'n:- 5.— lioundary. stone, No. 00,820. in the British Museum. 

 Date, about 1200 B.C. 



{From ft Phutorjraph hij Meanrn. W. A. Maiutill.) 



indic.-ition as to whether the year would be an ordinary 

 cine or an intercalary one, that Capella had given in 

 the first month. There arc no bright stars suitably 

 placed to continue these indications for the succeeding 

 iniMiths of the ye:ir. 



This method by which the new moon was praetic;illy 

 used as a pointer for determining the return of the sun 

 to a definite constellation at the end of the solar year, 

 is utterly unlike the methods which writers have sup- 

 posed the ancient astronomers were accustomed to use. 

 But we know from an existing inscription, that it was 

 actually employi-d ; it was eminently simple ; it re- 

 (|uired no instruments or star maps ; it may have been 

 in use long before the constellations were mapped out ; 

 ;ind though rough, it was perfectly clficient, and would 

 give the mean length of the year with all the accuracy 

 that was then re(|uired. It had one drawback, which 

 the ancients could not have been expected to foresee. 

 The effect of precession would be to throw the be- 

 ginning of the year gradually later and later — roughly 

 speaking, by a day in every seventy years, and the 

 time no doubt came when it w.is noticed that the 

 seasons no longer bore their traditional relation to the 



