The advocates for the supposed increase of the land of Egypt on a foot in 100 years, pressed by this observation, which they cannot contradict, have chose to evade it, by supposing, without foundation, that a smaller measure of the Nile’s increase had been introduced by the Saracens to obviate the Nile’s scantiness, and this has landed them in a palpable absurdity; for, while the Nile failed, the introduction of a lesser measure would not have increased the crop; and, if the quantity of grain had been exacted when it was not produced, this would have only doubled the distress, and made it more apparent; this would never have occasioned the joyful cry, Wafaa Ullah, God has given us our desire, men Jibbel, alla Jibbel, the Nile has overflowed, from the mountains on one side of the valley to the mountains on the other. Besides, there is no country in the world, perhaps, but where this trick may be played with impunity, except in Egypt, for a reason that I am about to explain.
The extension of the land of Egypt northward, the distance between it and Cyprus, and the situation of Canopus, all shew, that no or very little alteration has been made these 3000 years. Dr Shaw, and the other writers, who are advocates for what has been advanced by Herodotus[144], that Egypt hath been produced by the Nile, have deserted this ground of maintaining their hypothesis, and have recourse to the Nilometer to prove, that the soil has increased in height, and that a greater quantity of water is necessary now to overflow the land of Egypt than was required in the days of Homer.
If the first part of their assertion can be proved, I shall make no sort of difficulty of giving up the other. But I rather conceive, that none of those who have written upon this subject hitherto, whatever degree of learning and information they may have possessed, have possessed sufficient data to explain this subject intelligibly. It seems, indeed, to have remained with the source of the river, a secret reserved for latter times.
It will be necessary for us first to consider what the use of a Nilometer was, for what cause it was made, and by whom.
It is scarcely necessary to observe, that, in every state or society, the product or revenue should be known, as well as what will be wanted for the supply of the necessities of the people. Now, it was only the ground overflowed by the Nile that could produce grain for the subsistence of the inhabitants and revenue of the state.
The first consideration, then, was, to know how much of the land of Egypt was overflowed in a given term of years, and how much grain was produced upon that average. This could only be ascertained by measuring, and they, therefore, settled with precision the land that was overflowed from the earliest times, and do so to this day. These actual measurements gave them a maximum and a minimum, which furnished them with a mean, and thus they were in possession of all the principles necessary for making a Nilometer, by dividing a pillar into corresponding cubits, and divisions of cubits called digits, placing it also firm and perpendicular, so as to be liable to no alteration or injury, though in the middle of the stream.
The first stated measure was certainly that mentioned in scripture, the cubit, secundum cubitum virilis manus, measuring from the center of the round bone in the elbow to the point of the middle finger[145]. This is still the measure of all unpolished nations, but no medium or term, expressive of its exact contents, having been applied, writers have differed as to the length of this cubit, and no standard existing to which it might be referred, a great deal of confusion has thereupon followed. Dr Arbuthnot[146] says, that there are two cubits in scripture, the one, 1 foot 9 inches, and 888/1000 parts of an inch, according to our measure, being the 4th part of a fathom, twice the span, and six times the palm. The other is equal to 1 foot 824/1000 parts of a foot, or the 400dth part of a stadium. I shall not inquire into the grounds he goes on; I believe, however, that neither are precisely the ancient cubit of the east, but both are too large; at least the Egyptian I found to be very exactly 1 foot 5⅗ inches, which is 2 inches more than father Mersenne[147] has made his Hebrew cubit. But this is of less consequence to us now, because Herodotus[148] informs us, that in his time, and probably at the first institution of a Nilometer, the measure was the Samian cubit, which is about 18 inches English, or half an inch less than the ancient cubit.
The reader will then consider, that the divisions of this Nilometer were a representation of certain facts: That the Nile’s reaching to such a division corresponded to a certain quantity of corn that was sown, a proportion of the produce of which was to be paid to the king, the rest to go to the landlord and the labourer.
The Nilometer then ascertained the contract between king and people on these terms, That, in the event of so much corn being produced by the land of Egypt, such a tribute was to be paid: But, in case a certain quantity of ground, less than that, was overflowed, or, which is the same thing, a lesser quantity of grain was produced, then the king was not to exact his tribute, because it was understood such a quantity only was produced as was sufficient for the maintenance of the landholder and labourer. This was referred to the Nilometer, whose division shewed to what height the Nile had risen. Men appointed by the sovereign were to superintend this Nilometer, and to publish the height of the Nile, whilst the reason why the king was to have the direction of the Nilometer, and not his subjects, was very obvious, though it has not yet been understood, because the king could not gain by substituting false measures, whereas the people might.
The Nile, though in an average of years it brought down nearly the same quantity of water, yet, in particular ones, it varied sometimes more and sometimes less. It is likewise observed, like most other rivers, to run more on one side of the valley for some years than to the other. The consequence of this varying and deviation was, that though, upon the whole, the quantity indicated by the Nilometer was the same, yet nobody knew his quota, or what proportion of the whole was drawn from the property of each individual; as for this they were obliged to apply to actual mensuration. Supposing a man’s property was a section of the land of Egypt, of 12,000 feet from the brink of the river to the mountain, and of any given breadth, 4000 feet of this perhaps were overflowed, whilst the other 8000 remained dry, and above the level of the water. The tenant, after having measured, did not till then know what his farm of 12,000 feet would give him for that year, only 4000 of which had been overflowed by the water, and was then fit for sowing; for this he paid his landlord the highest rent laid upon cultivated land. But the 8000 feet that still remained were not equally useless, though not overflowed by the inundation; for 4000 of the 8000, which lay by the bank of the river, could be overflowed by machines, and by the labour of man, when, for a certain time, the river was high enough to be within reach of machinery; so that the value of this 4000 feet to the farmer was equal to the first, minus the expence and trouble it cost him for watering it by labour; for this, then, he paid one half of the rent only to the landlord.