176 NATURAL SCIENCE [September 1898 
points to their river-like ramifications, In the valleys containing 
these asar, detached patches of sand are sometimes found—the 
wreck, he believes, of a great deposit of sand, In such a deposit, 
rivers would soon cut down a deep channel. In the bottom of this 
channel pebbles and gravel would collect, then gravel, or sand, or 
mud layers, In time, the course of the river is diverted, the 
adjacent sands wear rapidly away, and the more compacted deposits 
of the river-bed longer resist denuding influences, and in the end 
stand out in bold relief as asar or eskers, 
One can hardly forbear exclaiming—Too clever by half! The 
author uses, to the full, the romancist’s privileges, He has every- 
thing he requires at hand and in abundance, and what he no 
longer requires he gets rid of with the readiness of a necromancer. 
Rivers have, no doubt, often struck out new lines of action for 
themselves. But here everything makes its bow and retires just 
when it has acted its part. 
THOMAS FITZPATRICK. 
Sr Ignatius’ CoLLEGR, 
GALWAY. 
(To be continued.) 
