196 



THE GEOLOGIST. 



Examples of every gradation may be seen, from the simple tuff-crater mth- 

 out any cone, to those which are entirely filled np by the scoria-cones. 

 Especially interesting are those which may be said to represent the middle 

 state, in which there is a small cone standing like an island in a large tuff- 

 crater, and surrounded by either water or swamp. Perhaps the most perfect 

 specimens of this kind occur at Otahuhu, and near Captain Haultain's estate. 

 Auckland itself is but over the centre of an old tuff-crater, from which fiery 

 streams once issued, and which has thrown out its ashes towards the hill on 

 which the barracks stand. In order to account for their various shapes, it 

 must be borne in mind that the cones of scoria were once higher, but on the 

 cessation of volcanic action they sunk down in cooling, and some have entirely 

 disappeared. 



That the Auckland volcanos were, in the true sense of the word, " burning 

 mountains," is proved not only by the lava-streams, which are immense in com- 

 parison to the size of the cones, but also from the pear-shaped volcanic bombs 

 which, ejected from the mountain in a fluid state, have received their shape 

 from their rotary motion through the air. That their eruptions have been of 

 comparatively recent date, is shown by the ashes that everywhere form the sur- 

 face, and from the lava-streams having taken the course of the existing valleys. 

 This is beautifully exemplified by the probably simultaneous lava-streams of 

 Mount Eden, the Three Kings, and Mount Albert, which, flowing through a 

 contracted valley, meet altogether on the Great North Hoad, and form one 

 large stream to the shore of the Waitemata. But many thousand years may 

 have passed since Rangitoto, which is probably the most recent of the Auck- 

 land volcanos, was in an active state. 



Many subjects of interest were passed over by Dr. Hochstetter with only casual 

 remarks, such as the quaternary formation in the Drury, Papakura, and Waiuku 

 flats ; the basaltic boulder formation ; the alluvial formations in the middle and 

 lower Waikato Basin, and other places ; and the clianges which are now 

 going on. 



The materials accumulated during his six month's sojourn in New Zealand 

 will require, he states, several years of labour to prepare for publication ; but 

 we are led to expect valuable results whenever his work is completed. 



Ancient CxiNOES. — Dear Sib, — There being now reason to believe that the 

 British Isles were tenanted by human beings who probably crossed over from 

 the great continent of Europe, the question of the antiquities of canoes becomes 

 highly interesting. Yery primitive indeed are these ancient canoes which have 

 hitherto been found — simply a part of a trunk of a tree split and hollowed out 

 with rudely formed adzes of flint, such as have been found in the craimoges* 

 in Ireland. 



Seventeen such canoes have been found in the strata formed by the river 

 Clyde ; for an account of which see the lecture on Geology, given by his Grace 

 tlie Duke of Argyll, before the members of the Glasgow Athenaeum, in January 

 of last year. 



Prom the fact of the canoes being found twenty feet below the siu-face, there 

 can be no doubt that they were entombed at a very remote period, for it must 

 have required a long time for those canoes to have become covered to that ex- 

 tent with the sand and gravel brought down by the river, in the waters of 

 which thay had sunk. Numbers of similar instances might be adduced of 

 canoes being found at considerable depths. 



Of the canoes above alluded to, one is stated to have been found in digging 



m|® " ^"^'^^"^-^"^ Antiquities of Stone, &c., in the Royal Irish Academy." Dublin 



