[18] “L’Astronomie Préhistorique.” Published in “Les Sciences Populaires, revue mensuelle internationale,” and issued separately by the administration des “Sciences populaires,” 15 Rue Lebrun, Paris.
The foregoing chapters will have shown that in dealing with the ancient monuments from an astronomical point of view, we have to consider chiefly the direction of the sight-lines, whether they are marked as in Brittany by long rows of stones--alignments; as at Stonehenge by an avenue; as in some of our British circles, by two or more circles the direction being indicated from the central stone of one to the central stone of the other, or finally by a single standing stone or barrow.
It is important then that before we proceed further in our inquiries we should consider how a meaning is got out of these directions, and I propose to devote this chapter to this question, so that the full use of the “azimuths” already referred to and others which are to follow may be fully understood.
There is another matter, at which I hinted on pp. 36 and 42. We have to inquire whether there are any stones or barrows marking the direction of the rising or setting of _stars_, as well as those which deal with the rising and setting of the _sun_ at different times of the year, which we have already found at Stonehenge and in Brittany. To face this question we have to consider the stellar as well as solar conditions of observations, and as the former are the simpler I will begin with them, especially as now there is no question whatever that the rising and setting of stars were provided for.
In continuation of my work in Egypt in 1891, and Mr. Penrose’s in Greece in 1892, I have recently endeavoured to see whether there are any traces in Britain of star observations, including those connected with the worship of the sun at certain times of the year. We both discovered that stars, far out of the sun’s course, especially in Egypt, were observed in the dawn as heralds of sunrise--“warning-stars”--so that the priests might have time to prepare the sunrise sacrifice. To do this properly the star should rise while the sun is still about 10° below the horizon. There is also reason to believe that stars rising not far from the north point were also used as clock-stars to enable the time to be estimated during the night in the same way as the time during the day could be estimated by the position of the sun.