53

plant cannot be procured without sending
to Australia for them.

I therefore collected and sent to Mel-
bourne specimens of rocks from many
parts of the Province, but more particularly from these ranges, and awaiting the
report. I made such excursions, especially
those described in my last letter to you
of the 11th instant, as, combined with
my explorations last year, enable me to
grasp all, or nearly all, the leading Geo-
logical features of the Province. By
this means I have narrowed the area
within which the search for minerals may
be expected to be successful, to the main
ranges of Rimutaka, Tararua, and Rua-
hine, with their spurs; the Aorangi range
at Cape Palliser, and the Kai Manawa
range in the Taupo country. I except
coal, of which more hereafter.

You will observe in Mr. Brough
Smyth’s report, that granite appears
among the specimens sent by me from
the Upper Hutt. This confirms the
opinion of that eminent geologist, the
Rev. W. B. Clarke. Doubts, however,
having been expressed, I have preferred
waiting for confirmatory evidence before
announcing the fact.

The theoretical proof which I gave in
my letter of December 18th, 1861, of the
existence of the “gold constants” in
the ranges, is now confirmed by the
discovery of granite, combined with the
evidence of the ancient character of the
bulk of the stratified rocks.

The granite is found in the ridge be-
hind Mr. J. Brown’s, in the Upper Hutt,
which bounds on that side the Mungaroa
swamp; and I have also found it on the
Mungaroa Hill. It is very fine grained,
and may easily be mistaken for a sand-
stone. It will doubtless be found nearer
Wellington, and may come into use as a
building stone. Near it is sandstones
with quartz veins, and mudstones of two
kinds, but I cannot yet say in what
sequence.

With regard to metamorphic rocks,
although the semi-crystalline sandstones
and other rocks may be said to be of that
character, yet as there are neither gneiss
nor mica schists within these ranges, it
will be advisable to abandon the term as
applied to the rocks generally. The fact is,
that the more the country is examined,
the less metamorphic do the rocks ap-
pear.

Thin quartz veins appear to penetrate
many of the rocks of these ranges,
riddling them in all directions; but the
larger quartz lodes are by no means so
prominent as in the gold regions of Aus-
tralia. That powerful lodes of quartz

and other vein stones however traverse
the rocks, every exploration tends to
show; and I can mention one quartz lode
fifteen feet wide and many others besides
of considerable thickness. I believe the
geological hammer now requires the aid
of the pickaxe and crowbar, to expose
the mineral veins.

Quartz lodes and other mineral veins
seem principally exposed in the fractures
of the anticlinal axes, which bears out
my original impression that minerals will
be found to lie deep, and this view will
also affect the argument as to the locality
of alluvial gold diggings.

If gold lies deep in the rocks while “in
situ” the wearing away of these rocks
(partially as here in deep and steep
valleys) will deposit it in the lower val-
lies only, and it may be plentiful there,
while entirely absent from the higher
ground.

It is suggestive that the rock taken
from Mr. Barraud’s well should resemble
rocks from a district where sulphide of
antimony and chrome iron are found,
these being two of the minerals reported
in the pyritous quartz lodes of the Petoni
road. The sandstone with plant impres-
sions, (No. 37,) from Porirua, being
decided, on the high authority of Pro-
fessor McCoy, as of Mesozoic age, which
with regard to coal, means oolitic, (the
age of at all events the upper beds of
the Australian Newcastle coal seams);
and the mudstones being declared Palaeo-
zoic and probably Silurian, it follows that
we have sedimentary rocks of two eras in
these ranges, folded however together in
such a way that I foresee great difficulty
in drawing the line of demarcation.

Mr. Brough Smyth’s remarks with re-
gard to gold seeking show a masterly
grasp of the subject.

A reference to my letter to you of
October 21st 1862, will show that I have
most faith in gold being found, in the
North Island, in the continuation of a
line from the Middle Island Gold Fields
to Coromandel, and that the present evi-
dence is in favor of micaceous and talcose
schists as the best gold bearing rocks of
New Zealand; but I have also strong
reasons to show, why the search for drift
gold in this Province should not be
hastily abandoned. I will first of all
dispose of Barraud’s well. This well is
sunk for a few feet only through a sand-
stone and a felspar-tho siliceous rock.
These rocks were said to be intersected
by a vein stone, which was covered with
rubbish when I visited the well, and un-
fortunately on the following day it was
bricked up. There is neither drift nor