w, 



of New Zealand \ 423 



glacier rivers in later pleistocene times. We must not, however, lose sight of 

 the fact that as apparently none of those coming from the central chain 

 reached the sea in this district, another favourable circumstance was added for 

 the preservation of the estuary and fluviatile deposits, lying upon the dolerite, 

 as well as of the loose young tertiary strata immediately below it. 



11 This dolerite plateau begins on the summit of Mount Horrible, the slopes 

 of which, towards the Pareora and its northern tributary, are very steep and 

 precipitous. The flat summit, consisting of dolerite identical with that of 

 Harper's Hills in the Malvern Hills, forms vertical escarpments for about 100 

 to 150 feet, from the numerous fissures of which a fine vegetation grows, 

 giving additional beauty to the picturesque scenery. A deep and straight valley 

 runs here, as in the Malvern Hills, west of this great escarpment, suggesting 

 at once that these dolerites deposited on the bottom of the sea were ejected 

 by a longitudinal fault or fissure in the tertiary strata by which the valley is 

 bounded on both sides. This valley, at the junction with the Pareora, is, 

 according to barometrical measurement, 312 feet above the level of the sea, 

 whilst the highest summit of Mount Horrible reaches to an altitude of 1138 

 feet. 



"The capping of dolerite forms generally a horizontal sheet on that 

 summit, although at some localities a dip towards east of as much as ten 

 degrees at the edge of the escarpment may be observed. 



"In travelling eastwards, after half-a-mile, the horizontal line of the 

 dolerite changes, and the mountain begins to have a small slope, which is 

 greatest above Mr. King's shepherd's hut, the foot of Mount Horrible being in 

 fact situated here. This shepherd's hut, distant about seven miles from 

 Timaru, lies 686 feet above the level of the sea." 



" Here at this shepherd's hut begins, properly speaking, the dolerite 

 plateau, overlaid by silt, sloping at an almost uniform angle to the sea, and 



dolerite rocks in some gullies only, which have their beginning either 

 in the eastern slopes of Mount Horrible, or even on the plateau itself for the 



notwithstanding their local origin 



bee 



beneath 



This occurrence gave me an opportunity to convince myself that, as far as 

 I was able to judge, only one large sheet was spread on that plateau, which 

 with a slight gradual slope dipped towards east, whilst it had a nearly horizontal 

 extent towards north and south, the fall being, as it seems, very slightly 

 towards both directions. The fall for the last seven miles being only about 



lin 



became conscious of another 



dolerite stream as it advances towards east thins out so as to be, in some 



