56: 



NA TURE 



[April 12, 190 



Of the sight-lines studied so far, those to and from 

 the Longstone and the holed stones seem the most 

 important. The Longstone, 1 : J miles to the N.E., 

 is a monolith 10 feet high on the western side of a 

 hill; it is visible from the circle though furze has 

 grown round and partly hidden it. 



The meanings of the various alignments seem to be 

 as follows : — 



Dec. N. Star Date 



Arcturus 



1 Solstitial 



May sun 

 Pleiades 



Apex of Cam 42 33 



Barrow Soo' distant 40 29 



Two barrows 900' distant 25 20 21 

 Holed stones 23 2 20 



Longstone 16 2 



Stone 9 15 



Regarding the possible solstitial align 

 declinations obtained may be neglected 

 azimuths and angular heights of the hills 

 determined with a good theodolite. A 

 — 10' in the angular elevation, and hence 

 in the resulting declination, would bring 

 given by the barrows to about 2000 B.C. 



The position of the Longstone is well 



2330 B.C. 



'97° ,. 



.. 1270 B.C. 



merits, the 



until the 



have been 



change of 



about that 



1 the date 



worthy of 



The May-sun alignment, it may be noted, differs 

 from that from the circle. The heights of hills 

 when determined may give us the same solar declina- 

 tion; that now used gives the declination of the sun 

 for April 28 and August 15 in our present calendar. 



Regarding the alignment on Lanyon Quoit, it need 

 only be pointed out that the Pleiades date obtained 

 is some 200 years after the date obtained for the 

 analogous alignment from the circle, showing that 

 if these two monuments — the Tregeseal circle and 

 the Longstone — have any relationship, the removal to 

 the high plain, now known as VVoon Gumpus and 

 Boswen Commons, was an afterthought improve- 

 ment. 



I next come to the holed stones, not only the nest 

 of them not far from the circle, but the famous 

 Mln-an-tol itself. 



I had heard before going to Tregeseal that the four 

 holed stones shown on the Ordnance map had been 

 knocked down and set up again (not necessarily in 

 their old places) two or three times. Mr. Horton 

 Bolitho and Mr. Thomas, however, in their examina- 

 tion wire convinced that the largest of them has 



leans tVzstiuiarcto 



Wii.. 



sUakiL 



f '/3. 



B. 



18/fO 



<fl& 2 



ftoSK****' 



Cc><' 



)«a*ir. 



s, IQA OK LaJUjOf 



Amp. of Line A B = 25°= Dec I6 C 



Fig. 6.— Plan of the Men-an-tol from Lukis showing that it was an apparatus for observing the sunrise in May and August in 

 one direc'.ion and the sunset in February and November in the other. Sun's declination. 16 N. or S. 



attention. Several very fine monuments which mark 

 the surrounding horizon are visible from it in 

 azimuths with which other monuments have made us 

 familiar. They are as follows : — 



Alii 



Hill, 



Longstone to Men-an-tol ... N. 50 30 E. ... o 34 

 ,, 9 Maidens 



(Boskednan) N. 54 o E. ... 1 o 

 ,, W. Lanyon Quoit N. 67 o E. ... o o 



,, Lanyon Quoit N. 72 45 E. ... o o 



These value,, ( ,f which the angular heights of the 

 hills were determined approximately from the con- 

 tours on the i-inch Ordnance map, lead us to the fol- 

 lowing declinations : — 



Alignment 



Longstone to Men-an-tol 

 Longstone to 9 Maidens 



(Boskednan) ... 

 Longstone to W. Lanyon 



Quoit ... 

 Longstone to Lanyon 



Quoit 



1 Jn Cornwall this is the name generally 



NO. I902, VOL. 73] 



never been moved. They also express the belief that 

 the 1 it hers are not more than a foot or so from their 

 original positions, and that this change is only due 

 to their re-erection by Mr. Cornish after they had 

 fallen down. So far I have heard nothing of the 

 direction of the hole in the stone which retains its 

 original position. 



Another interesting matter is that the explorers in 

 question were able to trace an ancient stone alignment 

 from the circle to the holed stones. 



I have long held that these holed stones were 

 arrangements for determining an alignment. The 

 famous Odin stone at Stenness, long since dis- 

 appeared, was, if we may trust the very definite state} 

 nients made about its position, used to observe the 

 Barnstone in one direction and the chief circle in the 

 other. 



["he azimuths suggest that theodolite measures may 

 show that the Tregeseal stones might have been used 

 in the same way; they, the Longstone and Lanyon 

 quoit, arc in nearly the same straight line, the align- 

 ment, holed stones to Longstone and Lanyon quoit, 

 being X. 67° I"... so that the May sunrise may have 

 been noted in this wav. 



