any fresh opening of the ground. By 

 these means and by special excursions for 

 the purpose of geological investigation 

 which as we have seen he began to make 

 in his College days, he acquired a broader 

 and more accurate conception of the 

 geological structure of the southern half 

 of England than any of his predecessors. 

 Moreover, his rectory lay in the heart of 

 the great Yorkshire coal-field where the 

 progress of the mining industry continu- 

 ally brought geological questions to his 

 notice. 



It was at Thornhill, during the leisure 

 which his clerical duties permitted, that 

 he was able to carry on those important 

 investigations in physics and astronomy 

 with which his name will always be 

 associated. In the same quiet retirement 

 he devised and constructed the various 

 forms of original and ingenious apparatus, 

 with which he solved or illustrated the 

 problems that presented themselves to his 

 ever active intellect. He continued to 



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