Stonehenge and Other British Stone Monuments Astronomically Considered

by Sir Norman Lockyer

We find plentiful evidence that the worship of the solstitial sun such as was carried on in Egypt at Karnak and at other places[125] was introduced into Britain some time after the May-year worship was provided for in the monuments.

Although some of the alignments already discovered are in all probability solstitial, the variation of the sun’s solstitial declination is so slow and takes place between such narrow limits that a most careful determination of the actual azimuths and of the angular heights of the various horizons must be made before any definite conclusion as to dates can be arrived at. The necessity for this care is illustrated in the paper on Stonehenge[126] communicated to the Royal Society by Mr. Penrose and myself in 1891, where, after taking the greatest precautions, the resulting date was in doubt to the amount of 200 years in either direction.

So far Stonehenge is the only temple at which these observations have been made, so that for the other alignments contained in the following list no dates can yet be given.

Monument.	Alignment.	Az.								Decl. (provisional).							Season.	Date B.C.
Stonehenge	Direction of avenue	N.	49	°	34	′	18	″	E.	23	°	54	′	30	″	N.	Summer (R)	1680
Boscawen-un	Circ. to fine menhir	N.	53		30		0		E.	22		58		13			Summer (R)
	Circ. to Blind Fiddler	N.	54		30		0		E.	22		24		12			„
Tregaseal	Circ. to row of holed stones	N.	53		20		25		E.	22		53		26			Summer (R)
	Circ. to two barrows 900′ distant	N.	50		0		0		E.	24		7		0			„
Longstone (Tregaseal)	Mèn-an-tol to Longstone	S.	50		30		0		W.	24		33		0		S.	Winter (S)
The Hurlers	N. circ. to S.E. stone	S.	50		50		0		E.	24		17		20		S.	Winter (S)
Stanton Drew	Gt. Circle to N.E. circle	N.	51		0		0		E.	23		48		46		N.	Summer (R)
Stenness	Circle to Hindera Fiold	N.	39		30		0		E.	24		3		15		N.	Summer (R)
	Barnstone to Maeshowe	N.	41		16		0		E.	—							„
	Circ. to Ward Hill tumulus	S.	41		0		0		E.	—							Winter (R)
	Circ. to Onston tumulus	S.	36		30		0		W.	—							Winter (S)
	Circ. to tumuli	N.	37		0		0		W.	—							Summer (S)
(R) = rising.(S) = setting.

I cited an alignment at the Hurlers which marked the rising point of Betelgeuse. This star warned the summer solstice sunrise at about the Hurlers’ date. So far, however, I have not yet found any suggestion of its use elsewhere.

At Shovel Down and Challacombe on Dartmoor there are avenues pointing a few degrees west of north. The sight-lines along these avenues would mark the setting-point of Arcturus at the time that that star (setting) warned the rising of the sun at the summer solstice; but this use cannot be considered as established, as Arcturus would scarcely set before its light was drowned in that of the rising sun. The absence of darkness in high summer in these latitudes and the bad weather in the winter may both be responsible for so few alignments for the solstices.

The Equinoctial Year Monuments.

The equinoctial pyramid and Babylonian cult in vogue in Egypt in the early dynasties (4000 B.C.), with the warning stars Aldebaran (March) and Vega (September), was represented in Greece at a much later period. The facts for Greece, according to Mr. Penrose, are as follows:—

			Decl.					Day.		Year.
										B.C.
March.
Nike Apteros	Spica (setting)		+	6	°	10	′	Mar.	17	1130
Juno Lacinia (near Croton)	α-Arietis		+	7		27		„	28	1000
Paestum (Neptune)	Spica (setting)		+	3		5		„	22	535
Gergenti (Hercules)	„		+	2		30		„	30	470
September.
Rhamnus (Themis)	Spica	(rising)	+	6	°	0	′	Sept.	17	1092
Tegea (Minerva)	„	„	+	5		51		„	18	1075
Syracuse (? Minerva)	„		+	4		30		„	20	815
Athens (dedication unknown)	„		+	4		17		„	23	780
Rhamnus (Nemesis)	„	„	+	4		5		„	22	747
Bassæ (Apollo)	„	„	+	3		57		„	22	728
Ephesus (Diana)	„	„	+	3		57		„	25	715
Syracuse (Diana)	„	„	+	2		22		„	26	450
Ephesus (Diana) (re-orientation)	„		—					Oct.	6	355

In Britain equinoctial alignments are not wanting, but so few have been traced that I have reserved them for future inquiry.