[ 447 ] 



Line of the j 

 P. J. Mar 



To Richard Taylor, Esq. 



LVII. On the Anticlinal Line of the London and Hampshire 

 Basins. ByY.i. Martin, Esq. 



My pear Sir, 



AS you have with much kindness hitherto afforded me space 

 in the Philosophical Magazine for the publication, in 

 ewtenso, of everything I have had leisure to bring before the 

 public on the much- vexed question of the Weald Denudation, I 

 beg the favour of a continuance of your good offices in the same 

 direction. 



By some the subject may be considered rather stale ; but so 

 long as there exists a doubt on the public mind of whether we 

 are to refer the phaenomena of the great denudations around us 

 to the slow sempiternal erosion of weather and water, as we see 

 them now in operation, or to call in the assistance of seasons of 

 paroxysmal violence and activity under other conditions, any 

 contribution which tends to throw light on such a subject can- 

 not be viewed with indifference. 

 I am, dear Sir, 



Your obliged friend and Servant, 



P. J, Maiitin* 



In my description of some of the parallel lines of elevation 

 which constitute the great anticlinal, and by their contortion 

 broke up the superficial strata and prepared them for removal, 

 at p. 50. vol. ii. 4th series, Phil. Mag., will be found the follow- 

 ing foot-note : — " Of the manner in which these parallel linea 

 may pass uninterruptedly and sometimes silently through a 

 country, we have a good example in the case of Portsdown Hill 

 in Hampshire, High Down near Worthing in Sussex, and the cliffs 

 of Seaford in the same county, all elevations of the same cha-, 

 racter, lying in the same course east and west, with a dip opposed 

 to the prevailing one of the intervening country. An elevatory 

 force acting with greater intensity at these points can alone ex- 

 plain the coincidence.^^ I had previously described these emi- 

 nences in my publication in 1828 as chalk outliers-by-protrusion. 

 Within the last two years a better acquaintance with the country 

 has shown me that the line in question does not pass through it 

 so clandestinely, but that the chalk is brought to the surface, 

 obscured here and there by " drift ^^ in all the linp of coun- 

 try south of the South Downs from Seaford by High Down, 

 through the Manwode, south of Chichester, and by Ports- 

 down into Hampshire, as far as Fareham and Titchfield, where 

 it is lost under the Hampshire tertiaries. In all this course 

 of at least sixty miles, tertiary formations are to be found 



