The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1903-10-22

the lava in Mokuaweoweo is lighter
| than that in Kilauea that it rises SC
much higher. In fact, it is as solid tnera
as in Kilauea. The explanation has oc-
| Cured to me that molten lavas rise
the higher the smaller the conduits in
which they rise from their subterra-
| mean reservoirs.
An illustration is afforded by the
"spouting horns on the seacoast, where
the ocean rushing into caverns of rock,
drives columns of water through small
openings to the height of 40 or so feet
| above high water mark. We see an
other illustration in water conveyed in
pipes, which jets the higher the smaller
the orif1ce.
However violent the subterranean
pressure may be, Kilauea does not over
flow, but only RACES the more fierceIy,
because it's passage from the chambers
below is SO large. But through the
vast mountain of Mauna Loa there is
no doubt a CONSTRUCTED conduit leading
upward; and there must be still small
er conduits to the assures on the sum-
NIT rim. On this theory, the molten
lava rises higher through Mauna Loa
than in Kifauea. because Mauna Lua
has the smaller throat.
1t is therefore by no means certain
that there is no subterranean connec-
ton between the two volcanoes.
PAHOEHOE AND AA.
Another vexed question, of which
several solutions have been proposed,
is the mode of formation of the two
strongly contrasted forms of lava
known as ''pahoehoe" and "aa." The
to 81 of
comparative smooth and uniform lava,
quietly; the latter to tracts of broken
lava, as though it had cooled when
tossing like an ocean in a storm, and
had then been broken up by earth
quakes. AS Mr.. Brigham states, mo
| words can convey an idea of it's hor-
rible roughness and hardness"
My own belief is that "aa'' has been
formed simply by Instructions break
, ing the quiet flow of molten lava. Ev-
cry observer has noticed that "pahoe-
hoe" contains ducts and air chambers
having an upper crust contorted into
the shape of the waves and ripples OF
the flowing lava. The liquid lava has
evidently flowed in these ducts and
chambers, and at last flowing out has
left them empty with glazed interior
surfaces. In like manner torrents OF
lava have poured through caverns
down the mountains to the sea, and
flowing out have left the innumerable
caves. smooth and shining within, to
| be found all over the island. Now
when there are Instructions on the
! earth's surface or meeting flows, thi:
system of ducts is broken up, and frag.
ments of lava are carried along on the
surface, piling up higher than the ad
jacent "pahoehoe," like ice packs il
rivers, and sometimes rolling immense
boulders twenty and thirty feet high
which now stand on the "aa" with fh'
drip glistening over them. This theor!
is confirmed by the fact that "aa" i:
always higher than the adjoining "pa
hoehoe," and also by the fact, which
especially noticed in the flow of 1853
that wherever there are open spaces il
lava. flows (kipukas) the old lava un
der the flow is found to be "pahoehoe'
under 'pahoehoe" and "aa" under "aa.
1 ARRANGEMENT OF CRATERS.
| While surveying the region, I wa
extremely. interested in the arrange
| ment of the craters; and now havin.
determined the situation of more thai
!, fifty of them on Mauna Loa, Hualala
and Mauna Kea. I have ascertaine,
that there is method in their arrange
ment. They are not arranged rela