chap. vii. Elevation of the Land. 159 



Evidence more or less distinct of a change of level 

 between the land and water, has been detected on 

 almost all the land on this side of the globe. Capt. 

 Grey, and other travellers, have found in southern 

 Australia upraised shells, belonging either to the recent, 

 or to a late tertiary period. The French naturalists 

 in Baudin's expedition, found shells similarly circum- 

 stanced on the S.W. coast of Australia. The Rev. W. B. 

 Clarke l finds proofs of the elevation of the land, to the 

 amount of 400 feet, at the Cape of Good Hope. In the 

 neighbourhood of the Bay of Islands in New Zealand, 2 

 I observed that the shores were scattered to some height, 

 as at Van Diemen's Land, with sea-shells, which the 

 colonists attribute to the natives. Whatever may have 

 been the origin of these shells, I cannot doubt, after 

 having seen a section of the valley of the Thames River 

 (37° S.), drawn by the Rev. W. Williams, that the land 

 has been there elevated : on the opposite sides of this 

 great valley, three step-like terraces, composed of an 

 enormous accumulation of rounded pebbles, exactly 

 correspond with each other : the escarpment of each 

 terrace is about fifty feet in height. No one after 

 having examined the terraces in the valleys on the 



1 ' Proceedings of the Geological Society,' vol. iii. p. 420. 



2 I will here give a catalogue of the rocks which I met with near 

 the Bay of Islands, in New Zealand : — 1st, Much basaltic lava, and 

 scoriform rocks, forming distinct craters ; — 2nd, A castellated hill of 

 horizontal strata of flesh-coloured limestone, showing when fractured 

 distinct crystalline facets : the rain has acted on this rock in a 

 remarkable manner, corroding its surface into a miniature model of 

 an Alpine country : I observed here layers of chert and clay iron- 

 stone ; and in the bed of a stream, pebbles of clay-slate ; — 3rd, The 

 shores of the Bay of Islands are formed of a feldspathic rock, of a 

 bluish-gray colour, often much decomposed, with an angular frac- 

 ture, and crossed by numerous ferruginous seams, but without any 

 distinct stratification or cleavage. Some varieties are highly 

 crystalline, and would at once be pronounced to be trap ; others 

 strikingly resembled clay-slate, slightly altered by heat : I was un- 

 able to form any decided opinion on this formation. 



