interesting original observations. Of 

 these the most remarkable is that which 

 recognised the important overlap of the 

 Cretaceous series of Yorkshire whereby 

 almost the whole of the underlying 

 Jurassic formations are concealed for a 

 space of some twenty miles a feature in 

 the geological structure of the country 

 of which the full import was not under- 

 stood for many years after his time. He 

 evidently accepted Michell's opinion that 

 the yellow limestone which immediately 

 overlies the Coal-measures of Derbyshire 

 and Yorkshire could not be the same as 

 that which overlies the Lias, but must 

 belong to a lower platform in the suc- 

 cession of formations. 



In the course of years, with his eyes 

 constantly on the alert for fresh light on 

 geological questions, Michell made many 

 original observations that well deserved to 

 be published, but with characteristic 

 modesty he refrained from putting them 

 in print. At the same time, as in his 



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