The Hawaiian gazette., 1894-01-16

/ seems more probable tnat tney orig
mated from calcareous hot springs,
secondary results of the eruption.
Possibly escaping steam may have
been the chief agent in their forma-
ton, the lime and phosphate which
they all contain in rather large pro
portions being derived from the de
composition of the gravel on the
spot. Such deposits must have a
bearing on the fertility of the soil,
considering how deficient our soils
are in general in lime.
In the gravel bed near the Luna
| lilo Home there is singular relation
of such calcareous and phosphate
deposit to the gravel, which here
evidently lies just where Madame
Pele placed it. The lower stratum Of
the gravel appears whitened in
places as though it had imbi5ed
from below water impregnated with
mineral. The line of demarcation be-
tween the black and the whitened
material is sharply de6ned-not per
fectly horizontal, in some places
showing in section a straight line, IN
others the whitened material exhibit
ing numerous conical (msmmillary)
projections upward. The sand is not
cemented, or is very slightly cement
ed by the intruding material, which
consists of carbonate and phosphate
of lime.
Clean black sand, several feet IN
thickness overlies this formation,
compelling one to believe that the
lime has been drawn up FROM be-
meath, unless it penetrated from
above on the side whence the sand
has been removed. In the upper
strata OF the sand deposit there are
numerous specimens of what appear
like fossil tree trunks and branches.
On examination these are found to
consist of sand similar to that IN
which they are embedded cemented
together by a whitish, yellowish or
rust colored msterial which proves to
be not lime but silica. Sometimes
these lie horizontally, confined to
single layer of the sand, and are
crowded together as closely as the
fleshy roots of the casssys plant. In
other instances their position is YER
teal or nearly so, and they traverse
several layers of the gravel. Often
they are crooked, not unfrequently
branching; in diameter they range
from one inch or less to six inches or
even foot or more. Familiar as
these objects are il the various
gravel pits about Honolulu, l confess
that l have not satisfactorily unray-
elled the mystery Of their formation.
In the same gravel pit, there is an
interesting bit OF history preserved.
The gravel had damned up the
stream which drains Punchbowl era
ter when there is a rain storm. 4
new channel was cut directly
through the gravel OF this pit, but
this in time became choked with
fragments of Punchbowl tufa, wash
ed down from the ridge near the
cemetery. and the water found
channel elsewhere. That the tufa is
really older than the gravel is shown
not far away, where the undisturbed
gravel rests on a tufa foundation.
The great explosive eruptions from
the Makiki group of vents gave to
large part Of Honolulu, as We have
seen. a deep fertile soil. Southeast
of this area, stretching from Moiliili
to Waiaiae and Diamond Head there
is region which has been flooded,
probably at a somewhat earlier date,
with liquid lava. which has conse-
quently as yet only a scsnty soil, be-
tween the bare lava blocks. The
source Of this lava was the crater of
Telegraph Hill.
On the other hand portions of Ho.
nolulu owe their soil to disintegra-
ton of The tufs of Punchbowl which
westhers easily, and yields fine
grained red soil. In some parts of the
city, the reef rock mas scarcely any
covering of soil, while in the extreme
western part, the surface con
sists of the ancient lava forms-
ton which seems to have re-
sisted pertinsciously the tooth of
time. 1t has only a scanty soil con-
sisting Of disintegrated lava.
In the valley region and about the
estuaries of streams there is of
course a good deal Of alluvisl de-
post, but even the valley, as far
north at least as the cemetery, re-
ceived its fiery baptism of sand from
the Makiki craters.
Microscopicsl examination of the
gravelly soil of Honolulu, shows that
it contains in astonishingly large
numbers perfectly formed crystals of
divine scarcely at all water worn,
but often partly or wholly crusted
with oxide of iron. These crystals
are commonly studded with minute
black octahedrs of magnetic, and
multitudes of these latter crystals
also exist in the soil, their presence
revealed whenever a stresmlet of
water runs down the street after
rain, the crystals being thus segre-
gated as fine sparkling black mag
netic sand.
Even the soils formed by the rot
ting down of lsvss contain generally