This has chiefly depended upon the fact that the riches and population of ancient Egypt were so great that that people could afford to build a temple to a particular star, or to the sun’s position on any particular day of the year. The temple axis along the line pointing to the celestial body involved, then became the chief feature, and tens of years were spent in lengthening, constricting and embellishing it. [Illustration: FIG. 12.--The axis of the Temple of Karnak, looking south-east, from outside the north-west pylon (from a photograph by the author).] From one end of an Egyptian temple to the other we find the axis marked out by narrow apertures in the various pylons, and many walls with doors crossing the axis. There are seventeen or eighteen of these apertures in the solar temple of Amen-Rā at Karnak, limiting the light which falls into the Holy of Holies or Sanctuary. This construction gives one a very definite impression that every part of the temple was built to subserve a special object, viz., to limit the sunlight which fell on its front into a narrow beam, and to carry it to the other extremity of the temple--into the sanctuary, where the high priest performed his functions. The sanctuary was always blocked. There is no case in which the beam of light can pass absolutely through a temple (Figs. 12 and 13). [Illustration: FIG. 13.--Plan of the Temple of Ramses II. in the Memnonia at Thebes (from Lepsius), showing the pylon at the open end, the various doors along the axis, the sanctuary at the closed end, and the temple at right angles.] In Britain the case was different, there was neither skill nor workers sufficient to erect such stately piles, and as a consequence one structure had to do the work of several and it had to be done in the most economical way. Hence the circle with the observer at the centre and practically a temple axis in every direction among which could be chosen the chief directions required, each alignment being defined by stones, more or less distant, or openings in the circle itself. Now for some particulars with regard to those parts of Stonehenge which lend themselves to the inquiry. The main architecture of Stonehenge consisted of an external circle of about 100 feet in diameter, composed of thirty large upright stones, named sarsens, connected by continuous lintels. The upright stones formerly stood 14 feet above the surface of the ground. They have nobs or tenons on the top which fit into mortice holes in the lintels. Within this peristyle there was originally an inner structure of ten still larger upright stones, arranged in the shape of a horseshoe, formed by five isolated trilithons which rose progressively from N.E. to S.W., the loftiest stones being 25 feet above the ground. About one-half of these uprights have fallen, and a still greater number of the imposts which they originally carried. [Illustration: FIG. 14.--One of the remaining Trilithons.]