Correspondence — Prof. 8. J. Shand. 575 



the flints were fixed in such a manner that a moving mass of ice or earth 

 slipped over, scratching the upper face and ' retouching ' the opposite. 



" One can often see that the predominating direction of the scratches is 

 almost normal at the chipped edges. Sometimes it is evident that the hard 

 substance which has incised a deep scratch has also dug, in some place where 

 its action has been prolonged, a little ' cupola of contusion '. Later the line 

 was continued as far as the more fragile edge, where the flint breaks, giving 

 a bunch of chips on the other side, thus simulating a concave scraper. 



' ' These explanations account for most of the so-called ' worked flints ' of 

 Pre- Crag beds and are very like those which you proposed. But it is astonishing 

 that to obtain a good type of ' rostro-carinate ' or similar ' implements ' so many 

 renewals of chipping of very different ages were necessary. 



" So it seems some of the chipped facets can be Eocene, and the continua- 

 tion of the same working could be Miocene or Pliocene. In any case, the 

 difference of the age between the successive chippings is so great that it excludes 

 the probability of the work of man. Otherwise very different actions seem to 

 have collaborated. Probably in the first bedding of these flints there was the 

 same compression as at Boncelles and Belle Assise ; afterwards they were 

 transported by diverse forces (more or less violent) which have left sometimes 

 traces extremely energetic. Others, specially, more or less deeply graven lines, 

 generally limited to one side, are to be considered. Often the other side is 

 similarly favoured by abundant ' retouching '. 



" I believe it is necessary to exercise very great caution and possess much 

 familiarity with both ' natural ' and ' artificial ' chipping of flint to enable one 

 to distinguish the difference. In many cases the natural fracture gives the 

 same appearance as the rough working and chipping of Man. So it is some- 

 times impossible to distinguish between the work of Nature or Man, and the 

 proof will come from another source than the morphology, which is too deceitful, 

 because the natural inclination of the human imagination is towards the 

 ' morphomanic ' . 



"As to the Ipswich skeleton, I think that it is senseless to present it as 

 ' Pre-Glacial '. The superdeposited soil is evidently due to the alteration and 

 transport of Boulder-clay down the slope. It is not Boulder-clay, it is a 

 dateless deposit (limon). The body had the position of a buried person, fairly 

 old, perhaps Neolithic. A grave dug in non-stratified soil would not have left 

 any trace after a considerable time. The decalcified soil of the clay and of the 

 grave ('|Middle Glacial') would not have permitted the preservation of a body 

 so old at such a shallow depth. 



"Finally, the position of the body is absurd. If the body had been 

 abandoned on the seashore it would have been dismembered, and the bones 

 would have been separated, rolled, destroyed. If the body is later than this 

 marine plateau (and it is, since it is partly in the overlying bed), then it dates 

 from this later bed ; but if so, if it was a ' moraine de fond ', the man could 

 not have been precipitated into it, neither dead nor alive, and a body on the 

 shore of the Middle Glacial sands would have suffered terrible injuries from 

 the glacier. The bones would have been crushed, disjointed, and dissolved by 

 the waters of the glacier. 



" All this is incomprehensible on the hypothesis of Mr. Moir, and, on the 

 contrary, is amply explained by yours and mine — burial in date probably late 

 prehistoric, in a modern soil derived by means of the alteration and the 

 reshuffling of the chalky Boulder-clay. 



" H. Beeuil." 



THE ALKALINE EOCKS OF SOUTH-WEST AFRICA. 

 Sir, — Since reading Mr. Holmes' paper on the alkaline rocks of 

 Angola (Geol. Mag., July and August, 1915) I have thought that 

 a brief note on the somewhat similar rocks occurring near Pomona and 

 in Namaqualand may be of immediate interest. I received a collection 

 of these rocks from Dr. A. W. Rogers in 1914, and I intend to visit 



