J. S. Lee — Recent Ice-action in N. Cldna. 



17 



surface of the hill, but are quite straight aud sharply defined. 

 Clearly, then, they are in no way comparable. 



It should, however, be mentioned that some of the fragments 

 possess peculiar smooth and striated surfaces. These can be easily 

 distinguished in the field from the polished and scratched surfaces 

 by the fact that they are either slightly warped, often with a glossy 

 brown incrustation, or exhibit rudely parallel wrinkles with a 

 projecting rim attached to the edges or the corners. Fragments 

 having this kind of surface look as if they had been partially 

 moulded in a more- or less plastic condition, or, what is more 

 likely, had been carved out by a neighbouring fragment shifted 

 under intense pressure. Such pressure, it is not difficult to imagine, 

 might have been set up by differential expansion of the rock-mass 



, ^^^Sfe^^'j! 



^^ 



(13 ^r;^" QfCsi^eEI^ Dole.ae 



Fig. 3. — Geological map of the 

 Sha-yuan-ling district. 



due to a sudden rise of temperature, or might well be exerted by 

 a great mass of ice that under special circumstances could have 

 concentrated its pressure on a number of crumbled rock-fragments. 

 When we reflect over the profound contortion of well-laminated 

 rocks produced by ice-action, this apparently wild assumption 

 seems plausibly to claim some respect. 



Judging from the occurrence of huge blocks of the hard quartz 

 sandstone 1-5 miles south-west of the Sha-yuan-ling and from the 

 north-easterly axial trend of the anticline already mentioned, it 

 seemed probable that the hypothetical glacier might have taken 

 advantage of the denuded anticline and directed its course towards 

 the north-east. If this be the case, we should expect to find traces 



VOL. LIX. — NO. I. 2 



