May 1 1, 1905] 



A' ^ TURE 



sun's ci-ntre, as we should do with the sun half risen, shown that the half-way time between an equinox and 



As a matter of fact, we must consider that part of a solstice is when the sun's centre has a declination 



the sun's limb which first makes its appearance above approximately 16° N. or S. In Orkney, with the 



the horizon; the first glimpse of the upper limb of [ latitude of 59°, assuming a sea horizon, the amplitude 



(he sun is in question, say, when the visible limb is of sunrise or sunset is 32° 21', the corresponding 



2' high. I azimuth being 57° 39'. 



LAT: I 



5°9r 



58 p 

 57 r 

 56 (^ 



55r 



54 1- 



53 r 



52 t- 



51 :- 

 50 r- 

 49 ^ 



48 I- 

 47'- 



J 



J-i 



AZIl 



lUTHS 



l-ic. 15.— The Azimmhs of ihe Sunrise (upper lin.b).it the Summe.- Sol.sl 



heighlofhillson I 



To make this quite clear I give a table which has 

 been computed by Mr. Rolston, of the Solar Physics 

 Observatory, showing the true azimuth with hills up 

 to i|° higli for lat. 59° N., the latitude of Stenness, 

 and 51°, nearlv the latitude of Stonehenge, of the 

 sun's upper limb for the solstitial year. 



: betn plotted, and the effect of the 



Now the most interesting and best defined line 

 with this azimuth on the Ordnance map is the one 

 stretching S.E. from the centre of the Stenness circle 

 to the Barnstone, with an azimuth of 57° 15'. The 

 line contains between the two points I have named 

 another stone, the Watchstone, i8i feet high, in the 



Soi.AR Azimuths 



1. Sun's centre ; uncorrected 



2. Upper limb ; corrected for semi-di; 

 3- 



4- 

 S. 



neter and refraclion , 



and hill i" high 



1. Sun's centre ; tincorrecled 



2. Upper limb ; correcled for .■■emidianieler and refraction 



The first important thing we learn from the table 

 is that although at any solstice the aziinuths of 

 the rising and setting of the sun's centre are the same, 

 the azimuths of the upper limb at the summer and 

 winter solstices differ in a high northern latitude by 

 some s°. The difference arises, of course, from the 

 fact that the limb is some 16' from the sun's centre, so 

 that considering the sun's centre as a star with fixed 

 declination, at rising the limb appears before the 

 centre, and at setting it lags behind it. 



It will also be seen that at sunrise hills increase the 

 azimuth from N., and refraction reduces it; while at 

 setting, hills reduce the azimuth from S. and refrac- 

 tion increases it. 



Not only does calculation prove the worship of 

 the May and June vears, but I think the facts now 

 before tJs really go to show that in Orkney the May 

 year was the first established, and that the solstitial 

 (June) year came afterwards, and this was the chief 

 question I had in view. 



I will begin with the May year. I have already 



NO. 1854, VOL. 72] 



and hill h" hiyh 

 ,, 1° ,< 

 „ ii° ,, 



precise alignment ; and from the statements made 

 and measures given it is to be inferred that a still 

 iTiore famous and perforated stone, the " Stone of 

 Odin," demolished seventy years since, was also in 

 the same line within the extremities named. 



If we may accept this we learn something about 

 perforated stones, and can understand most of the 

 folk lore associated with them, and few have more 

 connected with them than the one at Stenness. I 

 suggest that the perforation, which was in this case 

 5 feet from the ground, was used by the astronomer- 

 priest to view the sunrise in November over the Barn- 

 house stone in one direction, and the sunset in May 

 over the circle in the other. 



There is another eclio of this fundamental line ; 

 that joining the Ring of Bookan and the Stones of 

 Via has the same azimuth and doubtless served the 

 same purpose for the May year. 



But this line, giving us the May sunset and 

 November sunrise, not the December solstitial sun- 

 rise as Mr. Spence shows it, is not the only orienta- 



