The dawn of astronomy / A study of the temple-worship and mythology of the ancient Egyptians

by Sir Norman Lockyer

First of all we know that the temple was directed to the place of the sun's setting; and if the Egyptians wished to lead the narrow shaft of light which was bound to enter the temple, since it was directed to the sunset, they would have contrived the very system of gradually narrowing doors which we have found to be one of the special features of the temple.

The doors were considered as very important—and no wonder. In the account given of Thothmes III.'s restoration of the temple of Amen-Rā, we read that after the building had been constructed in a "position corresponding to the four quarters of heaven" the great stone gateways were erected.

"The first had doors of real acacia wood covered with plates of gold, fastened with black bronze and iron."

Then came a propylon (Bekhen) with three other gates connected with it covered with plates of copper, and the sacrifices were brought through these.[29]

This idea is strengthened by considering the construction of the astronomical telescope. Although the Egyptians knew nothing about telescopes, it would seem that they had the same problem before them which we solve by a special arrangement in the modern telescope—they wanted to keep the light pure, and to lead it into their sanctuary as we lead it to the eyepiece. To keep the light that passes into the eyepiece of a modern telescope pure, we have between the object-glass and the eyepiece a series of what are called diaphragms; that is, a series of rings right along the tube, the inner diameters of the rings being greatest close to the object-glass, and smallest close to the eyepiece; these diaphragms must so be made that all the light from the object-glass shall fall upon the eyepiece, without loss or reflection by the tube.

These apertures in the pylons and separating walls of Egyptian temples exactly represent the diaphragms in the modern telescope.

What then was the real use of these pylons and these diaphragms? It was to keep all stray light out of the carefully roofed and darkened Sanctuary; but why was the Sanctuary to be kept in darkness?

The first point that I wish to make is that these temples—whatever view may be entertained with regard to their worship or the ceremonial in them—were undoubtedly constructed among other reasons for the purpose of obtaining an exact observation of the precise time of the solstice. The priests having this power at their disposal, would not be likely to neglect it, for they ruled by knowledge. The temples were, then, astronomical observatories, and the first observatories that we know of in the world.

If we consider them as horizontal telescopes used for the purpose I have suggested, we at once understand the long axis, and the series of gradually narrowing diaphragms, for the longer the beam of light used the greater is the accuracy that can be obtained.

Independently of ceremonial reasons—there is a good deal to be said under that head—it is quite clear that the darker the sanctuary the more obvious will be the patch of light on the end wall, and the more easily can its position be located. It was important to do this on the two or three days near the solstice, in order to get an idea of the exact time at which the solstice took place. We find that a narrow beam of sunlight coming through a narrow entrance some 500 yards away from the door of the Holy of Holies would, provided the temple were properly orientated to the solstice, and provided the solstice occurred at the absolute moment of sunrise or sunset according to which the temple was being utilised, practically flash into the sanctuary and remain there for about a couple of minutes, and then pass away. The flash would be a crescendo and diminuendo, but the whole thing would not last above two minutes or thereabouts, and might be considerably reduced by an arrangement of curtains. Supposing the solstice did not occur at the precise moment of sunrise or sunset, and provided the Egyptians by any means whatever were able to divide the days and the nights into more or less equal intervals of time, two or three observations of the sun rising at the solstice on three different mornings, or of the sunset at the solstice on three different evenings, would enable a careful observer to say whether the solstice had occurred at the exact moment of sunrise or sunset, or at some interval between two successive sunrises or sunsets, and what that interval was.