Finally, I wish to lay claim to no originality in the views adopted. What I have aimed at in this paper is to work those views out, and to go more thoroughly into them than has hitherto been done, thereby making a contribution to the discussion of an unsolved problem, interesting alike to Engineers, Archæologists, and Classical Scholars.
As the metrical system is in use in Egypt, all dimensions and quantities are given throughout this paper in metres and cubic metres, and distances in kilometres.
| 1 metre | = 3·2809 feet. |
| 1 square metre | = 10·7643 square feet. |
| 1 cubic metre | = 35·3166 cubic feet. |
| = 220·097 gallons. | |
| 8 kilometres | = 5 miles (approximately). |
Discharges are given as so many cubic metres per day of 24 hours.
| 1,000,000 cubic metres a day | = 11·5741 cubic metres per second. |
| = 408·9775 cubic feet per second. |
Areas are given in feddans, which is the Egyptian acre.
| 1 feddan | = 4200·8333 square metres. |
| = 1·038 acre. |
R.L. signifies “reduced level,” or the level referred to mean sea-level:—e.g. “at R.L. 25·00” means that the spot, to which the figure relates, is 25 metres above mean sea-level; and “R.L. - 40·00” means 40 metres below mean sea-level.
A contour is the line running through all the points which are at the same level above or below mean sea-level.
An Egyptian pound, L.E., = 1¹⁄₃₉ English pound, £.