378 Transactions—G eology. 
It would require very strong argument to establish a volcano in the 
absence of any igneous rocks in situ. Now, in the Whanganui district, the 
whole country is composed of marine tertiaries up to the base of Ruapehu. 
There are no volcanic cones; there are no igneous dykes of any kind; 
there is not a particle of evidence that a volcano ever existed in the district. 
With the exception of the voleanic group of Ruapehu and Tongaiiro, I 
think I may safely say that there is no evidence of any volcanic cone in the 
Province of Wellington, and even of igneous dykes few have been found. 
The same remarks will apply to the Province of Hawkes Bay without 
exception. Taranaki has its own volcano, but it is a magnificent one ; 
while Auckland is thickly studded with volcanic cones of all sizes. Although 
Wellington has only the central group to boast of, yet this group, compris- 
ing Ruapehu, Tongariro proper, Ngauruhoe, and Puke Onake is superior to 
all the rest, even to Mount Egmont. There scems to be a strong tendency 
in the human mind to place volcanoes in the Whanganui district. Even 
- Hochstetter has been persuaded by somebody to put one at Taupiri, where 
no volcano exists. Taupiri is composed of the usual marine tertiaries. 
I hope Mr. Purnell will excuse my criticism. If he can find any volcanic 
or igneous rocks in situ, he may have a case for argument. I assert that 
there are none to be found thus in the Whanganui district, neither in the 
shape of volcanic cones, nor of dykes of dolerite, trachyte, basalt, green- 
stone, or any other igneous rock whatsoever. 
One might as well place a volcano in London as at Whanganui. I will 
undertake to find plenty of igneous rock in London, brought as ballast. 
I have seen chalk flints in the road metal of the streets of Sydney. I did 
not, therefore, suppose that we must find a cretaceous formation there, 
because I saw that the flints had come from London as ballast. 
If we find volcanic products, such as pumice or tufa in any district, and 
are unable to find a volcano in situ, from which these may have come, then 
it may be a fair argument to suppose that, at some time or another, @ 
voleano must have existed, although all direct traces of it had disappeared. 
But when we find the clearest cause and effect before our eyes, there is not 
the slightest necessity for adopting hypotheses. ; 
I am also extremly doubtful whether it would be competent for a sub- 
marine voleano to eject pumice. I never heard of such a thing. Pumice 
is simply fluid glass (obsidian) expanded by rapid passage into the atmo- 
sphere, An eruption under water, and therefore under great pressure, 1s 
not likely to permit the formation of this product. 
I should be happy to oblige Mr. Purnell in any reasonable way ; but a 
yoleano at Whanganui is too much to ask for. It would be a great and un- 
necessary expenditure of hypothetical power. 
