88 J. D. ENYS ON SAND-WOKN STONES FKOM NEW ZEALAND. 



Bamsay's opinion, to marine denudation. He stated that in the 

 neighbourhood of these curious crags there is plenty of loose sand; 

 and this having been blown with great force against the bases of 

 the pillars, has cut them away into their present fantastic forms. 



Mr. John Evans referred to various examples of stones polished 

 by blown sand occurring in this country. 



Prof. Boyd Dawkins remarked that if we wanted evidence of the 

 erosive power of blown sand we had only to consider the effects of 

 the sand-blast now so commonly used for the purpose of etching- 

 designs upon glass. He also cited examples in the African deserts 

 of stones polished by the natural sand-blast. He stated, however, 

 that he did not agree with Prof. Bamsay with respect to the origin 

 of the crags on Kinder Scout, which, he remarked, is a wet locality, 

 whilst, in order that it may cut in the manner suggested, the sand 

 must be dry. The shaping of these peculiar crags was, in his 

 opinion, due to the unequal weathering of rocks consisting of sand- 

 stones of unequal toughness. 



