The first important thing we learn from the table is that although at both solstices the azimuths of the rising and setting of the sun’s centre are the same, these azimuths of the upper limb at the summer and winter solstices differ in a high northern latitude by some 5°. 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.
![[Larger diagram]](#5911925350219446446_illo133lg.jpg.id-5624821674897267786.wrap-0.html.html){kind=link}
Fig. 37.—The Azimuths of the Sunrise (upper limb) at the Summer Solstice.
The values given in the table have been plotted, and the effect of the height of hills on the azimuth is shown. The range of latitude given enables the diagram to be used in connection with the solstitial alignments at Carnak, Le Ménac, and other monuments in Brittany.
Vertical axis from bottom: LAT. 47-59.
Horizontal axis from left: AZIMUTHS 37-56.
Curves from left: SEA HORIZON, HILLS 1⁄2°, 1°, 11⁄2°
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 refraction increases it.
This [diagram] and [table] should fully explain the variation of azimuth at sunrise caused by the fact that from our present point of view we do not deal with the sun as a star.