Fig. 1.—Present sun worship in Japan.
It may be well, however, in the present book to restate the underlying astronomical principles in the briefest possible manner; and this is the more easily done because, in the absence of measuring instruments, the horizon was the only circle which the ancient peoples could employ effectively, and we need only therefore consider it.
Indeed, whether we regard the Rig-Veda or the Egyptian monuments from an astronomical point of view, we are struck by the fact that the early worship and all the early observations related to the horizon. This was true not only for the sun, but for all the stars which studded the general expanse of sky.
Fig. 2.—The celestial sphere, conditions at the North Pole. A parallel sphere. N.P., North celestial Pole; N, position of observer.
We have therefore chiefly to consider the relation of the horizon of any place to the apparent movements of celestial bodies at that place.
Fig. 3.—The celestial sphere, conditions at the Equator. A right sphere. Q, standpoint of observer; PP, the celestial poles; EW, east and west points.
Fig. 4.—The celestial sphere, conditions in a middle latitude. An oblique sphere. In this woodcut DD′ shows the apparent path of a circumpolar star; BB′B″ the path and rising and setting points of an equatorial star; CC′C″ and AA′A″, those of stars of mid declination, one north and the other south; O, standpoint of observer.