Crawford. — Port Nicholson a Fresh-water Lake. 291 



locality higher than a height of about fifteen feet above the sea. To this I 

 replied in the negative. 



Cogitating over these matters, I have come to the conclusion that the 

 probabilities are that the land in this neighbourhood was never, since the older 

 rocks were elevated, at a lower level than about fifteen feet below that at 

 which it stands at present, and that at some time, probably during the 

 depi-ession of the tertiaries, it attained a great elevation, possibly equal to the 

 present extreme altitude of Tararua, viz., 5,000 to 6,000 feet, perhaps higher. 

 At this time it is reasonable to suppose that Cook Strait did not exist, and 

 that the islands were united. 



If we follow up the main chains of Tararua and Ruahine to the northward 

 we find a gradual rise of the tertiary beds which rest on the flanks of these 

 mountains, attaining, at the Manawatu, a height of between 400 and 500 feet, 

 and in the vicinity of the Kaimanawa range a height of 2,700 feet. 



These rocks extend from eocene to pliocene, and many changes of level no 

 doubt occurred during their deposition, but while in course of formation they 

 must have been beneath the sea. 



My supposition is, that previous to the time when they were in course of 

 formation there was an oscillatory movement which depressed the more 

 northern rocks and i-aised those in this vicinity ; while, at the time when these 

 tertiaries were raised above the sea level, the movement was in an opposite 

 direction, the whole of the west coast tertiaries emerged and were raised at 

 their northern limit to a great elevation, while the land in this neighbourhood 

 was depressed until it sunk below its present level, and probably at the same 

 time Cook Strait was formed and the islands separated. 



I have formerly remarked on the various terraces which may be observed 

 on the coast towards Terawiti, and have supposed them to mark old beaches, 

 showing lines of rise of the land. As I think no remains of marine origin 

 have been found in them, I now suggest that they mark the banks and various 

 levels of an ancient river, the other bank having disappeared in the waters of 

 the Strait. With a supposed high elevation and greater mass of land, we may 

 suppose a larger river or rivers than any which we now possess in this 

 vicinity, and some things may thus be accounted for which are difficult of 

 explanation otherwise. Thus, if we consider the boulder and gravel 

 formation which forms the isthmus between Evans and Lyall Bays, and on 

 which the sand-hills are a mere excrescence, it is difficult at first siglit to 

 perceive where the boulders came from. No boulders or gravel are now 

 washed up on either shore, and it is not perceptible why, if the land stood at a 

 lower level of fifteen feet, boulders should then be thrown up. Still less 

 could they be thrown up if the land stood at a higher elevation than it does at 

 present. 



