I ULY 



igil] 



NATURE 



1 1 



kirelenting hand of man; others have deteriorated in 

 1 vigour as they have gradually come under 

 fee yoke. The horse, however, forms a notable excep- 

 tion, having from obvious reasons improved in 

 p]i\ sique and gained in strength. Such minor .changes, 

 changes of degree rather than of kind, are all that 

 evolution can lay claim to have effected in these 

 stubborn mammalia within the compass of some 

 thousands of years during which Mentone has 

 known the two extremes of climate and tempera- 

 ture. 



Another great assistance rendered by the work of 

 M. Boule is that he has enabled us with more certi- 

 tude than was possible before to reconstruct the milieu 

 of certain of our Palaeolithic ancestors; for, from the 

 fauna it is not difficult to realise the nature of the 

 flora or the conditions of the climate. With the in- 



THE TYPES OF WATER WAVES. 1 

 1~\ R. CORNISH has produced an attractive and 

 *-' valuable book. The volume is not the less 

 valuable in that it is primarily descriptive, and in that 

 the author shows great caution and reserve as regards 

 speculative explanations. This caution is indeed 

 amply warranted. The mathematical theory of water 

 waves, successful as it is up to a certain point, is 

 limited in its application by the fact that it contem- 

 plates only specially simplified conditions. In par- 

 ticular, owing to the restriction to small amplitudes, 

 it can at present offer little in the way of explanation 

 of various important natural phenomena, where what 

 is technically called "turbulent" motion comes into 

 play. Laboratory experiments, on the other hand, 

 require elaborate and costly arrangements, which are 

 only provided with difficulty even when a definite 







Fig. t.— Wave-track of St 



and other Water Wa 



lip and di' 



formation thus obtained we can npprach the stone and 

 bone implements which the man of that remote date 

 has left, and deduce more confidently what were the 

 purposes they served. A knowledge of the fauna is 

 thus seen to be the key which will most successfullv 

 unlock many of the sealed chambers of man's past. 

 Apart, however, from all this, the study of the extinct 

 Pleistocene fauna possesses in itself great and abiding 

 interest, and dull must be the archaeologist or anthro- 

 pologist who does not desire further knowledge con- 

 cerning these early companions of man whose bones 

 lie commingled with his in river drift and cave 

 floor. 



The book is a most valuable contribution to science, 

 and reflects the greatest credit on evervone con- 

 cerned. 



William Wright. 

 NO. 2178, VOL. 87] 



practical problem is in view ; and in some respects 

 the mere question of scale would impair their rele- 

 vancy. There remain only observations in the open, 

 such as the author has recorded in the present book. 

 The extreme difficulty of these, from a quantitative 

 point of view, is well illustrated by his discussion of 

 storm-waves at sea. 



The book is made very readable by the fact that 

 the author's interest in his subject is evidently aesthetic 

 as well as practical or scientific. He is fascinated by 

 the extraordinarily beautiful and varied types of wave 

 motion which are presented by nature, and has re- 

 corded a number of these, observed at sea or on land 

 in many parts of the world, in a series of remarkable 

 photographs. 



c f s of the Sea and 

 Pp. 374- (London : ' 



1910.) Price 



