63 

 THE RIGIDITY OF NORTH-WEST YORKSHIRE* 



J. E. MARK, SC.D., F.R.S. 



In thanking you for the honour you have done me by electing 

 me as your President for the year, I must assume that it is 

 not altogether undeserved, and I think a reason may be found 

 in that I, like my two predecessors in the Woodwardian Chair, 

 got much of my early training as a geologist in North-west 

 Yorkshire, and as the present Reader in Petrology at Cambridge, 

 the Unive;sity Lecturer in Economic Geology, and the Assistant 

 to the Professor, are Yorkshiremen, there is a happy connexion 

 between the Cambridge school of Geology and your county. 



Though not a Yorkshireman myself, I was born within 

 sight of the county, and one of my earliest recollections as a 

 child is of Ingleborough rising above the Lune Valley, 

 as seen from the high ground above Lancaster ; and since 

 that day the tract of country to which that hill belongs has 

 been to me a favourite district for study and recreation. I 

 regard it to a large extent as my geological school-room, and 

 was happy in my masters. The ancient slate-rocks of the 

 dales about Ingleborough were studied under the guidance of 

 McKenny Hughes, and before this I had examined the Car- 

 boniferous rocks, the glacial phenomena and the underground 

 drainage during many a walk over the hills with Tiddeman, 

 who first taught me practical geology. It would be impertinent 

 to talk of the importance of Tiddeman's work to an audience 

 of Yorkshire naturalists, who know and appreciate it so fully, 

 but I cannot refrain from saying a word about the man, whom 

 to know was to love. I was a schoolboy when I first knew 

 him, and for nearly half a century benefited by his friendship. 

 Some of you may know that he and I differed as to the inter- 

 pretation of certain geological structures in the West Riding, 

 of which he was the discoverer. It was perhaps presumptions 

 of the pupil to differ from his master, and although I believe 

 I was right, the matter must be regarded as still unsettled. I 

 mention it here to state that my action made no difference in 

 our friendship, unless, indeed, his treatment of me was, if 

 possible, more kindly than before, as though to show me that 

 he bore no ill-will. And now, when I look back to those 

 bright days spent in that favoured district, I am ever conscious 

 of that happy friendship. 



In considering the geological structure of North-west 

 Yorkshire one must also deal with parts of Westmorland, Dur- 

 ham, North-east Cumberland and portions of Northumberland, 



* Presidential address to the Yorkshire Naturalists' Union, delivered 

 at Bradford, December 4th, 1920. 



1921 Feb. 1 



