(1) The unfinished obelisk of AswÂn lies in a quarry on the south-east side of the mediÆval Arab cemetery, being about twenty minutes walk from the Cataract Hotel. It is approached by a small valley leading up south-eastwards from the track of the old Barrage railway.

Up to the time of the visit of King Fuad—then Sultan—in the winter of 1920–21, only about 22 metres of the obelisk were exposed to view, the remainder running down into a vast heap of blocks and chips. The curious trench, made round the obelisk for the purpose of detaching it from the rock, has long interested visitors, and His Majesty expressed a desire that the whole obelisk be cleared in order to obtain, if possible, new data as to ancient methods of quarrying, and to expose a unique monument.

I wish to tender my thanks to Mr. Somers Clarke for his kindness in putting his notes on the quarrying of granite at my disposal, and for reading and criticising my MS. before sending it to press; to Prof. Flinders Petrie for reading the proofs and giving many valuable suggestions; to Mr. W. GolÉnischeff for the references on the Anastasi papyrus and the HammÂmÂt inscriptions; to Mr. D. Watt, Resident Engineer of the AswÂn Barrage, for the loan of books on the properties and working of granite and of surveying instruments from the Barrage works; to the Geological and Chemical Departments (sections 13 and 44) for their report on specimens submitted to them, and to the Survey Department for taking much trouble in preparing my plans for publication.

Mr. A. M. MacGillivray, of AswÂn, took the photographs shewn on plate II and plate V, nos. 1 and 2, and has kindly permitted them to appear here.

(2) I began the work shortly after the departure of King Fuad, and soon found that the excavation would be more extensive than I had at first supposed; the length of the obelisk had reached 36 metres by April 1921, and the chip-heap, covering the butt end of the obelisk, began to shew signs of giving way. I had made arrangements, as regards the angle of the chip-heap, supposing that the obelisk was not larger than any of the known obelisks. Thirty-six metres was a surprise, so, as Ramadan was approaching, I abandoned the work for the season and applied for a further credit to make a complete clearance. This was done in the winter of 1921–22 by MahmÛd Eff. Mohammad, Inspector of EdfÙ, assisted by Mustafa Eff. Hasan, ‘chef de fouilles’ of the same district. I visited the site from time to time whenever my {2} other work permitted, but it was not till the end of the tourist season that I had sufficient time to study the obelisk.

During the removal of the chip-heap, we found some hundreds of large granite blocks thrown from a quarry above on to the obelisk; these had to be cut into two, and sometimes into four, before our workmen could handle them. At first we borrowed men from the Selugia quarries, but afterwards we employed local stonemasons, who proved more satisfactory, as they did not all want to be raises.

The total cost of the clearance was L. E. 75.

A word of explanation is, perhaps, needed on the system of weights and measures used in this volume. It has been the custom of my Department to insist on metric scales in all plans. In the text, however, I enter somewhat deeply into the stresses and strains set up in the granite, and since nearly all the English engineering text-books and tables use the ton-inch units, I have adhered to the English system, reducing the metric linear measures to inches in my calculations. The tonne and the kilogramme-per-square-centimetre still convey little to the average English-speaking engineer, who has to have recourse to his slide-rule before being able to realise the strains set up when they are given in metric units.