CHAP. xvii. EARTHQUAKES IN NEW ZEALAND. 349 



have witnessed, so late as January 1855, in the northern 

 island of New Zealand, a sudden and permanent rise of land 

 on the northern shores of Cook's straits, which at one point, 

 called Muko-muka, was so unequal as to amount to nine feet 

 vertically, while it declined gradually from this maximum of 

 upheaval in a distance of about twenty-three miles north 

 west of the greatest rise, to a point where no change of level 

 was perceptible. Mr. Edward Koberts, of the Eoyal Engineers, 

 employed by the British Government at the time of the 

 shock in executing public works on the coast, ascertained 

 that the extreme upheaval of certain ancient rocks followed 

 a line of fault running at least ninety miles from south to 

 north into the interior ; and, what is of great geological 

 interest, immediately to the east of this fault, the country, 

 consisting of tertiary strata, remained unmoved or stationary ; 

 a fact well established by the position of a line of nullipores 

 marking the sea-level before the earthquake, both on the 

 surface of the tertiary and paleozoic rocks.* 



The repetition of such unequal movements, especially if 

 they recurred at intervals along the same lines of fracture, 

 would in the course of ages cause the strata to dip at a high 

 angle in one direction, while towards the opposite point of 

 the compass they would terminate abruptly in a steep escarp 

 ment. 



But it is probable that the multiplication of such move 

 ments in the post-tertiary period has rarely been so great as 

 to produce results like those above described in Moen, for 

 the principal movements in any given period seem to be of 

 that more uniform kind spoken of at p. 334, by which the 

 topography of limited districts and the position of the 

 strata are not visibly altered except in their height relatively 



* Bulletin de la Socie~te Geologique municated to me by Messrs. Eoberts 

 de France, vol. xiii. p. 660, 1856, and Walter ManteU. 

 where I have described the facts com- 



