(26) The suggestion, put forward by Donaldson, that the Egyptians softened the granite by chemical means before using the chisels on it, is not worthy of serious notice, as a glance at the tool marks shews that the granite was quite hard, and behaved in exactly the same way as it does under modern tools. His other suggestion, that the granite was first pounded to render it more workable, cannot be accepted as the explanation, as how did they pound the bottom of the wedge-slots? A far more reasonable suggestion is that the granite was cut by chisels of dolerite or similar {27} basic rocks. Mr. Firth tells me that, except for the grinding of the cutting-edge, they occur naturally in the Wady Alaqi. A series of trials with such a chisel left me entirely unconvinced, the more so since many of the old chisel-marks shew that a narrow-edged tool had been used. From my own experiments, I can believe that the Egyptians _could_ have cut granite with a copper chisel, but more time is spent sharpening the tool than in cutting the stone, and the expenditure of metal would be appalling in any but the smallest works, but I cannot admit that copper tools, as we know them, could have ever been used to cut hard quartzite, which gave the Egyptians no special trouble, if we judge by the huge chambers which they cut, polished and transported, as in the case of the burial chamber in the Hawara Pyramid. It has also been suggested that the copper chisels were fed with emery, but anyone who has handled a chisel will appreciate the impossibility of feeding the tool with emery; on the other hand, emery may well have formed the basis of the polishing process, and have been regularly used in stone drilling and sawing. (27) How, then are we to explain this problem? Much as I hate to admit it, I am driven to the conclusion that the ancient Egyptians possessed some simple method of tempering copper to the hardness of modern tool-steel[11]; even now copper with 2 % of alloy may, by heavy hammering, be brought to the hardness of mild steel. This has been suggested by many writers, and examples of tools are known—Wilkinson quotes one in volume II, p. 255—where the malletted end of the chisel was worn by the blows, but where the point was sharp; of course that might be explained by the fact that it had just been re-sharpened, but I have myself seen a chisel where the cutting-edge was chipped in the same manner as a modern steel tool instead of being burred. I was unable to purchase this specimen, but I tried the point with a knife, and was able to scratch it as I could any other piece of copper; the temper, therefore, must have been temporary (cf. WILKINSON, _Manners and Customs_, vol. II, p. 255, and PETRIE, _Arts and Crafts_, p. 100).