15 



in clay, peat and calcareous layers, and this difference is well explained by the 

 more uniform movement of the waters which made those older deposits. 

 Though in the average the velocity of the waters was not greater— jierhaps 

 somewhat smaller— at that time than it is now, yet the want of stagnant parts of 

 the river-courses and the comparative uniformity of the slope as well as of the 

 breadth of the valleys could hut have such consequences. They are, however, 

 less conspicuous in the plain of Tokio than in many other countries, for instance 

 in the plain of northern Europe, where the hulk of Ijie older alluvial deposits 

 (corresponding to the American Terrace- or Champlain-period) is almost entirely 

 linilt up hy the so-called 'Thai-Sand,' or sand of the valleys. 



