CrawrorD.—On the Igneous Rocks of the Province of Wellington. 877 
In this paper Mr. Purnell introduces to the Whanganui district a sub. 
marine volcano, and it may be at once perceived that I cannot leave this 
novel and unexpected visitor from the lower regions unchallenged. 
Thave further reasons for taking this step, as I understood that Mr. 
Duigan has also in a paper, read this year, introduced voleanoes into the 
Whanganui district. As I did not hear this paperread, and do not know its 
argument, I will confine my remarks to Mr. Purnell’s paper, which is now 
before me, as a discussion of it will fully settle the question of Whanganui 
volcanos. 
If any one is responsible for a correct statement of the igneous rocks of 
this Province, I am that person, and it would certainly be a curious fact if 
I had overlooked such a prominent matter as volcanoes at Whanganui, a 
district which I have traversed in all directions. 
The necessity which Mr. Purnell seems to feel for establishing a sub- 
marine volcano is really quite unnecessary. The whole process of con- 
veying volcanic material is going on every day and all day long before the 
eyes of any one who chooses to look. 
Pumice floats down the Whanganui River in such quantities that it 
would be no difficult matter for a ship anchored in the river to intercept it 
by putting out nets, and so load the ship, and make the pumice an article 
of commerce. Volcanic ashes are no doubt also washed down, and the 
harder voleanic rocks are rolled down as boulders. When the Whanganui 
River stood at a higher level—that is to say, before it cut itself so deep a 
channel—its waters would spread more to right and left over the surround- 
ing country, and would there leave deposits of pumice, of volcanic ashes, 
or even of hard igneous boulders. 
Around the volcanic groups of Ruapehu and Tongariro there are im- 
mense areas covered with pumice. From this, pumice has been washed 
down the Whanganui River, and there, in many parts, forms thick deposits 
in the narrow valley. The river cuts through these deposits, and wearing 
away the banks, constantly floats immense quantities down stream, which 
are either deposited further down or carried out to sea. 
When Ruapehu and Tongariro were in full blast, we may suppose the 
quantities of pumice and volcanic ashes brought down the river to have 
been enormous. 
There are plenty of voleanic products at Whanganui ; but none in original 
situ. From Taranaki volcanic boulders are rolled along the beach. From 
Tongariro similar boulders are brought down the river, and at last carried 
out to sea, while in addition, as above stated, pumice and possibly voleanic 
ashes are always travelling down the river. 
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