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we went ashore, and encamped for dinner under the shade of a 
magnificent Pohutukaua tree ( Metrosideros torment os a ) , the trunk of 
which measured 24 feet in circumference. In the back-ground rugged 
cliffs of a most remarkable appearance are seen. Tremendous 
blocks of volcanic rocks, of trachyte, andesite and basalt — blocks 
of 4 to 6 feet diameter, angular and sharp pointed, and of all 
colours, red, green, brown and black — are cemented together into 
a conglomerate or breccia, forming huge masses of solid rock, in 
which, nevertheless, a rude stratification may be observed. From 
some of those blocks I succeeded in knocking out neat crystals of 
pyroxene. Here we have the commencement of those strata of vol- 
canic conglomerate and breccia which, more than 1000 feet thick, 
compose the Titirangi Chain, and from the Manukau Northhead 
stretch as far as close to the Kaipara Harbour, forming the rugged, 
rocky precipice of the Westeoast. 1 Proceeding along the beach 
of Puponga peninsula in a N. W. direction to Karangahape Bay, 
upon the banks of which, on a less favourable site, a township, 
called Cornwallis, has been laid out — of which, however, as 
yet, not a single house stands — the lower strata appear; first 
banks of a soft , rusty sandstone , which is sprinkled black with 
fine grains of magnetic iron; and farther on layers of sandstone 
and shale, such as the Isthmus of Auckland is composed of. 
One is able to convince oneself here, that the violent convulsions, 
which formed those colossal masses of volcanic conglomerates, are 
of a more recent date, than the formation of the tertiary strata 
on the Waitemata. Here also, in several places of the beach, black 
titaniferous iron-sand has been found of the same description as the 
iron-sand, which is an ingredient of the sand along the whole West- 
coast of the northern Island; which especially on the coast of Ta- 
ranaki covers the shore for miles, and which, according to ex- 
periments made with it in England, is said to produce most 
1 As far as these volcanic conglomerates on the sea-coast are exposed to the 
action of the sea-breeze, they form solid masses of rock, while farther inland they 
are totally decomposed into variegated clays. 
