(13) These stones, which I propose to call ‘pounders’, are nearly spherical, and vary between 8 and 13 inches in diameter, their weights ranging between 9 and 15 pounds. On assembling a large number of them and examining them closely, it is seen that nearly every one of them has one, and often several, brownish-red stains, which are never seen on the inside when a ball is broken. The balls are of almost natural formation, and shaped by the action of water during the ages, the stains being at the part where the block touched the parent rock before being washed out. The stains are caused by fissures in the original rock, which allowed the water to enter, decomposing the surfaces. They consist of ferric oxides from the ferrous silicates. I have buried some hundreds of these pounders under the west retaining-wall and elsewhere, as even their weight did not prevent them from being carried off freely by souvenir-hunters. Mr. C. Firth has given me some stone chisels from the district of Wady Alaqi, in Nubia, for comparison with the pounders used on the obelisk. He tells me that rounded stones of similar appearance to the pounders may be seen in large numbers in the wadys of the Eastern Desert both above and below Aswân. I took some pieces of pounders, together with the chisels, to the Geological Museum, Cairo, where they were examined by Mr. W. F. Hume and Hassan Eff. Sadek, who have kindly furnished me with the following report: ‘It has been concluded (as the results of the examination supported by specific gravity determinations made in the Government Analytical Laboratory), that the stone from which the chisels were made was a diorite, the specific gravity varying from 2.75 to 2.87. The pounders, on the other hand, are composed of dolerite, which is a more basic rock than the diorite, with a specific gravity of 2.93 to 3.05. Though rocks of this nature are present in the Aswân Cataract region (see J. BALL, _First or Aswan Cataract_, pp. 79 and 86), it is quite conceivable that the material for these implements has come from other localities. Rocks of this type abound in the Second Cataract at Wady Halfa and have been used as pounders in many gold-mining localities of the Eastern Desert, such as the Baramia Mine where they are of wide distribution.’ My own examination of the Aswân quarries has not revealed stone of precisely the same quality as that of the pounders, and in so far tends to support the idea that the material for chisels and pounders is derived from some other region. The wear on the pounders is not distributed evenly over the whole surface—which would be expected if they had been used entirely by hand—but appears in patches, shewing that the pounders were used in one position until the bruising surface in use had become flat, and therefore useless. When a pounder is newly used, the bruising surface nearly always is found at a point directly opposite to the stain, possibly as there is always a slight flattening there.