[11] There has lately been a rumour that a method has been discovered in America for tempering copper, and that a company is being formed for its exploitation; if this is true, it will relieve archæologists considerably, who have been at their wits’ end for a good explanation for the last 50 years. If this is the true solution, it is probable that the knowledge died out when the use of iron and steel became general, as its value in not producing sparks could hardly have been foreseen. It is not surprising therefore that the knowledge died out when it was no longer a necessity. It might be remarked that instead of having a method of greatly hardening copper, the Egyptians might have been able to temper iron. The experiments on iron and its properties during the last century have been innumerable and, had there been a method, apart from the introduction of carbon, of tempering iron to a very great hardness, I think that it would certainly have been discovered by now. In our present state of knowledge, it is best to leave the subject as an open question. {29} CHAPTER V. TRANSPORT OF OBELISKS. (28) Before entering into the question of the transport of obelisks, it may be as well to give extracts from ancient writers. They throw very little light on the problem, the Roman and Greek writers only giving what seems to be third-rate hearsay information, while the Ancient Egyptians usually confine themselves to statistics as to the numbers of men employed. King Menthuḥotpe IV sent an expedition of 10,000 men to the Wady Hammâmât quarries to bring in a sarcophagus, and records that it took 3,000 sailors from the Delta nomes to remove the lid, measuring 4 by 8 by 2 cubits, from there _to Egypt_. This seems to shew that a pressed gang of the amphibious Delta inhabitants from the lakes had been taken out to the quarries. At any rate we are told that “not a man perished, not a troop was missing, not an ass died and not a workman was enfeebled” (BREASTED, _Ancient Records_, I, 215). This was more fortunate than the expedition of Ramesses IV quoted below, but it gives no details of the various kinds of artisan employed. In the reign of Amenemḥêt III, an official, also called Amenemḥêt, was sent to the same place to obtain 10 statues of 5 cubits high. The personnel consisted of (BREASTED, _A. R._, I, 313): Necropolis soldiers 20 Sailors 30 Quarrymen 30 Troops 2000 Under Ramesses IV, a large expedition was again sent to the Wady Hammâmât for monumental stone. It numbered 8362 persons. Breasted sums up the personnel as follows (_A. R._, III, 224):