380 EHRENFELD— JOINTING AS A FUNDAMENTAL FACTOR 



tion.-5 The description-'^ given of the breaking down of these 

 island masses is that of the remains of a plateau structure shown 

 throughout the island group, with fjords which are characteristic 

 alike of the small islands and "the mainland." Against these 

 island remnants of a plateau carrying the remnants of the horizontal 

 layers of Carboniferous, Permian and Miocene deposits "the sea 

 unceasingly beats in the further destruction of the fragments of 

 the plateau, while strange pillars and towers indicate the wide ex- 

 tent of the islands " destroyed in this way. This description with 

 the illustrations given in the literature referred to shows plainly 

 enough the destruction of the land masses by lines which are mani- 

 festly joint lines, and is fairly characteristic of similar sea coast 

 shapes to be seen along the shore of the North Atlantic ocean both 

 on the American and European sides. 



These towers and pillars referred to are strikingly similar to 

 some structures referred to in a recent valuable paper by Barrell,-'' 

 in which the origin of certain plains along the eastern Atlantic coast 

 is connected with former marine erosion. The discussion of this 

 paper brings out the question of marine origin for those upstand- 

 ing land masses commonly known as " monadnocks." 



Those interested in the arguments for the fact of marine plana- 

 tion along the Atlantic coast of North America should consult 

 Barren's paper. 



It has long been a thought of mine that it might be possible to 

 have established some time the demonstration of " monadnocks " 

 being residues left from a jointing structure in which mechanical 

 disintegration had played a predominant part. As may be seen in 

 the discussion of the paper referred to this idea is inherent in the 

 conception of marine plains as developed by Barrell. 



In the largest view of the matter Bear Island, Spitzbergen and 

 other like land remnants are "monadnocks," if by this term is 

 meant any residue of a former land surface which stands as a seg- 

 ment not now reduced to a general level. This sort of residual 



25 Norske Nordhavs Exped., Bd. s; also Pctcrm. Mittcil., 1870, S. 249 ff. 

 Other references and a German translation will be found in '' Unser Wissen 

 von der Erde," von A. Kirchofif, Vol. 3, pt. 2, pp. 394 ff. 



-<^ " Unser Wissen," etc., as cited pp. 395 ff. 



^~ Bull. Gcol. Soc. Amcr., Vol. XXIV., 1913, pp. 688 ff. 



