It is impossible to fix the time of the building of Syene; upon the most critical examination of its hieroglyphics and proportions, I would imagine it to have been founded some time after Thebes, but before Dendera, Luxor, or Carnac.
It would be no less curious to know, whether the well, which Eratosthenes made use of for one of the terms of the geodesique base, and his arch of the meridian, between Alexandria and Syene, was coeval with the building of that city, or whether it was made for the experiment. I should be inclined to think the former was the case; and the placing this city first, then the well under the tropic, were with a view of ascertaining the length of the solar year. In short, this point, so material to be settled, was the constant object of attention of the first astronomers, and this was the use of the dial of Osimandyas; this inquiry was the occasion of the number of obelisks raised in every ancient city in Egypt. We cannot mistake this, if we observe how anxiously they have varied the figure of the top, or point of each obelisk; sometimes it is a very sharp one; sometimes a portion of a circle, to try to get rid of the great impediment that perplexed them, the penumbra.
The projection of the pavements, constantly to the northward, so diligently levelled, and made into exact planes by large slabs of granite, most artificially joined, have been so substantially secured, that they might serve for the observation to this day; and it is probable, the position of this city and the well were coeval, the result of intention, and both the works of these first astronomers, immediately after the building of Thebes. If this was the case, we may conclude, that the fact of the sun illuminating the bottom of the well in Eratosthenes’s time was a supposed one, from the uniform tradition, that once it had been so, the periodical change of the quantity of the angle, made by the equator and ecliptic, not being then known, and therefore that the quantity of the celestial arch, comprehended between Alexandria and Syene, might be as erroneous from another cause, as the base had been by assuming a wrong distance on the earth, in place of one exactly measured.
There is at Axum an obelisk erected by Ptolemy Evergetes, the very prince who was patron to Eratosthenes, without hieroglyphics, directly facing the south, with its top first cut into a narrow neck, then spread out like a fan in a semicircular form, with a pavement curiously levelled to receive the shade, and make the reparation of the true shadow from the penumbra as distinct as possible.
This was probably intended for verifying the experiment of Eratosthenes with a larger radius, for, by this obelisk, we must not imagine Ptolemy intended to observe the obliquity of the ecliptic at Axum. Though it was true, that Axum, by its situation, was a very proper place, the sun passing over that city and obelisk twice a-year, yet it was equally true, that, from another circumstance, which he might have been acquainted with, at less expence of time than building the obelisk would have cost him, that he himself could not make any use of the sun’s being twice vertical to Axum; for the sun is vertical at Axum about the 25th of April, and again about the 20th of August; and, at both these seasons, the heaven is so overcast with clouds, and the rain so continual, especially at mid-day, that it would be a wonder indeed, if Ptolemy had once seen the sun during the months he staid there.
Though Syene, by its situation should be healthy, the general complaint is a weakness and soreness in the eyes; and this not a temporary one only, but generally ending in blindness of one, or both eyes; you scarce ever see a person in the street that sees with both eyes. They say it is owing to the hot wind from the desert; and this I apprehend to be true, by the violent soreness and inflammation we were troubled with in our return home, through the great Desert, to Syene.
We had now finished every thing we had to do at Syene, and prepared to descend the Nile. After having been quiet, and well used so long, we did not expect any altercation at parting; we thought we had contented every body, and we were perfectly content with them. But, unluckily for us, our landlord, the Schourbatchie, upon whom I had my credit, and who had distinguished himself by being very serviceable and obliging to us, happened to be the proprietor of a boat, for which, at that time, he had little employment; nothing would satisfy him but my hiring that boat, instead of returning in that which brought us up.
This could by no means be done, without breaking faith with our Rais, Abou Cuffi, which I was resolved not to do on any account whatever, as the man had behaved honestly and well in every respect. The janissaries took the part of their brother against the stranger, and threatened to cut Abou Cuffi to pieces, and throw him to the crocodiles.
On the other part, he was very far from being terrified. He told them roundly, that he was a servant of Ali Bey, that, if they attempted to take his fare from him, their pay should be stopped at Cairo, till they surrendered the guilty person to do him justice. He laughed most unaffectedly at the notion of cutting him to pieces; and declared, that, if he was to complain of the usage he met when he went down to Lower Egypt, there would not be a janissary from Syene who would not be in much greater danger of crocodiles, than he.
I went in the evening to the Aga, and complained of my landlord’s behaviour, I told him positively, but with great shew of respect, I would rather go down the Nile upon a raft, than set my foot in any other boat but the one that brought me up. I begged him to be cautious how he proceeded, as it would be my story, and not his, that would go to the Bey. This grave and resolute appearance had the effect. The Schourbatchie was sent for, and reprimanded, as were all those that sided with him; while privately, to calm all animosities against my Rais, I promised him a piece of green cloth, which was his wish; and so heartily were we reconciled, that, the next day, he made his servants help Abou Cuffi to put our baggage on board the boat.