May 21, 1891] 



NATURE 



59 



very considerable antiquity was possible in these observa- 

 tions met with very great difficulty. But the shortest and 

 the longest shadows recorded (700 years B.C.) do not really 

 represent the true lengths according to recent knowledge. 

 If anyone had forged these observations he would state 

 such lengths as people would find to-day or to-morrow, 

 but the lengths given were different from those which would 

 be made to-day. Laplace, who gave considerable attention 

 to this matter, determined what the real obliquity was at 

 that time, and proved that the record does represent an 

 actual observation and not one which had been made in 

 later years. 



The solstices and the equinoxes were therefore in all 

 probability thoroughly known to the Egyptians 4000 years 

 B.C., perhaps even 5000. We are then justified in* con- 

 sidering that the temples at Abydos and at Karnak are 

 really solar temples. The Egyptians marked the solstices 

 and the equinoxes not only by their temples but in their 

 calendars, which these temples enabled them to construct. 

 The Chinese had also this knowledge, but we have no 

 information that they possessed it at so early a date. 



In the next place, then, I propose to make a special study 

 of the temples at Karnak, because they are those which 

 are most capable of minute investigation. I do this in 

 order to see whether any other indications can be obtained 

 of any higher knowledge possessed by the Egyptians of 

 those early times. 



I must again point out that we deal with the solstices 

 in the case of the temples at Abydos and Karnak, and 

 with the equinoxes in the case of the pyramids, some 

 mounds in Babylonia, and the Temple at Jerusalem. 

 Since the labours of the French and Prussian Govern- 

 ments who have given such full records of Karnak, a 

 memoir on the temples has been published by Mariette, 

 which gives us not only plans, but precious information 

 relating to the periods at which, and the kings by whom, 

 the various parts of the temples were constructed or 

 modified. 



We may begin by the general plan of Thebes. We 

 find there a perfect nest of temples. No doubt those 

 which are still traceable form only a very small portion 

 of those which once existed, but however that may be, I 

 have now only to call attention to one or two among 

 them. In the general plan we see indications that on 

 both sides of the Nile there were temples pointing to 

 those special amplitudes which I have before referred to. 

 What we have first to do is to refer to the solstitial 

 temples, those which point to 26° N. or S. of E. or W., 

 in which we have undoubtedly indications of the early 

 attempts to observe, or to worship, the sun at sun-rising 

 and at sun-setting, at the critical times — the solstitial 

 times of the year. 



The first point that I wish to make is that these 

 temples — whatever views may be entertained Vi^ith regard 

 to their worship or the ceremonial in them — were un- 

 doubtedly 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. 



It is worthy of note that the direction of the temple 

 at Karnak is quite independent of the locality, it has 

 nothing to do with the presentation of the temple to the 

 Nile or to any other particular part of the landscape, and 

 that point, I think, is absolutely settled by the con- 

 sideration that we have temples at the same amplitude in 

 different localities up and down the Nile Valley, where, 



NO. I 125, VOL. 44] 



although they are parallel to each other, their presenta- 

 tion to the river in the different localities is very various. 



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 ? 



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 posi- 

 tion 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 sol- 

 stice occurred at the absolute moment of sunrise or sunset 

 according to which the temple was being utilized, prac- 

 tically 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 there- 

 abouts, and might be considerably reduced by arrange- 

 ments 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 at some interval between 

 two successive sunrises, and if the latter, what that interval 

 was. 



I now come to my next point, which is that here we 

 have the true origin of our present means of measuring 

 time — that our year as we know it was first determined in 

 these Egyptian temples and by the Egyptians. We have 

 seen that it did not require any great amount of astro- 

 nomical knowledge to- determine either the moment of 

 the solstice or the moment of the equinox. I think you 

 will agree with me that the most natural thing to begin 

 with was the observation of the solstice, for the reason 

 that at the solstice you can watch the sun day after day 

 getting more and more north or more and more south 

 until it comes to a standstill. But for the observation of 

 the equinox, of course, the sun is moving most rapidly 

 either north or south, and therefore it would be more 

 difficult to determine in those days the exact moment, so 

 that I have little doubt that what they attempted in the 

 first instance was to mark the absolute moment of the 

 solstice. If that be so, and if Masp^ro is right that 

 Abydos was built before Menes, then we know definitely 

 that the Egyptians could and did observe the solstices, 

 and knew what they were doing, 7000 years ago. 



Before I say anything more about the use of these 

 temples in determining the year, it is worth while to note 

 how very different the treatment of this subject was in 

 Egypt to what it was in Chaldaea and Babylonia and 

 among the Jews. We do of course in the Egyptian 

 inscriptions read of the moon, but in Chaldaea it would 

 seem that the moon was the chief thing worshipped, and 

 it was thus naturally the chief means used for measuring 

 time, and, as far of course as months were concerned, this 

 was quite right. In Chald;ca, where they were not de- 

 pendent upon the rising of the Nile, and where much 

 desert travel had to be undertaken at night, the moon and 

 the month were the points considered, and the sun was 

 hardly regarded at all from that point of view. An in- 

 teresting point connected with this is that, among any 

 of these ancient peoples, the celestial bodies which gave 

 them the longest period of time by which they reckoned 

 were practically looked upon in the same category. 



