The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1856-1888, 1883-03-31
RECENT EXPLORATION
Of the Volcanic Phenomena Of the He-
waiian Islands; by Captain C. z. Dutton.
(From a Letter to j. 4. Dana. Dated
Washington, D. c., Feb. 8, 1889
-. 90. &C ~ -. 1ArcH. -.

return iyr tie kind interest you took ~ nv jIUr-
ney and Tor tie valuable Suggestions You made me
prior to my departure. | therefore avail myself
% a convenient opportunity TO tell you briefly
some of the matters which mO-t particularly in
teIested me.
After making such purchases as were thou sht
necessary for my journey at HOuOlulu, / took the
inter-island steamer for the southern part OF Ha-
waii. 1 did not 90 to Hilo ct first, rs travellers
generally do, for after making inquiry, | came to
the conclusion that the southern part Of the is
land would be a much more advantageous position
from which to begin the study Of Mauna Loa and
KIlauea. The HilO side of the island is very
rainy. The field geOlogist quickly gets accus-
toned to every inconvenience and discomfort Of
travel except one, and that is mud and the more
he has to do with mud. the more he hates it. The
: iuthern district of the Island, Kau, is almost al
ways dry and the travelling good enough. fitted
out Il pack train with six packs, in regular Rocky
Mountain style. and my first journey, Of course,
was to Kilauea:' 1T is lar pleasanter to approach
the volcano from the kau side than from the HilO
side, and the journey was full Of interest. My
first visit to Nilauea lasted ten days, during which
| explored the great PIT thoroughly and also the
country round about. If | can rightly estimate
the accounts of observers who saw Kilauea forty
years or more ago, | should inler that the total
amount OF volcanic energy now manifested there
has very considerably diminished. There is diff
Guilty, however, IN forming an estimate OF how
much allowance should be made for the enthusiasm
and excited imaginations of travellers who for the
first time, and generally the only time, have be
held this wonderful spectacle. The great inner
pit, which was first described by Ellis in his Poly
nesian Researches, in 1898. and also by yourself,
in 184l, has been completely filed up. The great
outer cavity also has, | infer, become notably
shallOwer, having been partially filed by innum-
cradle over1Ows of lava. The inner cavity. which
once held u burning lake, is now represented by
two lakes, whose united surfaces have, l should
judge, an extent which is but a small fraction of
rho snrfara. ~ 81 old l,La Of E..tu ~ EGr -onr,
ago. These two lakes are both situated with
their surfaces at levels higher than the mean level
Of the main flow Of the pit. infer too that they
are much more languid and sluggish in their ac-
ton than the lake which you saw.
The height of the walls surrounding the pit
varies from 800 to 740 feet. There is abundant
evidence that the floor of the PIT sinks down more
Or less after every eruption within it, but pre-
sumably not to so great an extent as to compen-
safe the building up of the floor after the success
i've Out-pOurs OF lava, so that, on the whole, the
pit is probably growing shallower.
L watched. with the deepest interest, the action
of the lava in the lakes. The most accessible one
is now called the New Lake. 1t undergoes a
series of regular changes within a period Of about
two hours. When we reach the brink of it we
generally find it frozen over and quite black and
still, except at the edges, where we perceive a rim
Of fire. We observe also at many places upon
the edges a little sputtering and blowing out of
lava and hear a dull simmering sound. At length
a piece of the black lava upon the surface cracks,
turns down its edge and sinks, disclosing a patch
of liVid fire. Soon after, in some other part Of
the lake, at the edge, another piece breaks and
goes down. This becomes more and more fire.
quent until at last a hundred cracks suddenly
shoot through the entire surface, and, with a
grand commotion, numberless fragments of
the frozen surface plunge downward, leaving
the whole one glowing mass of lava. For
a few minutes the spectacle is very grand, but it
does not last long. The surface quickly darkens
and freezes over again, becoming black as before
and in this condition 1t remains for an hour or
two. The period between break-ups is not regu-
lar, being as short as forty minutes and as long as
two hours and n quarter.
The explanation of the phenomenon is, | think,
not difficult. When the lava first passes from the
liquid to the solid condition, while it's tempera-
ture is still near the melting point, but below it,
its density is less than that OF the lava below.
As the crust thickens and the surface becomes
cooler, it's density becomes greater than that of
the lava below, and its position then becomes I'M
stable. A slight disturbance produces a rupture,
and the sinking OF one fragment is quickly fol-
lowed by that of the others.
1t has been the custom to speak OF Kilauea as
being situated upon the TANKS Of Mauna Loa and
TO regard it as a mere appendage of that noun
tain. But it presents itself to me as a distinct
volcano having no more connection with Mauna
LOa than Mauna Kea has. Into the discussion
of this | cannot now enter.
From Kilauea | went TO Mauna Loa. Ny first
objective point was the source OF the last great
eruption of l880-S1. 1t is reached with difficult
ty on account Of the rOughness Of the clInker
fields. or . aa, :" as 1T is termed IN the Islands.
The vents are situated from twelve to eighteen
hundred feet below the summit, upon the north
eastern spur. Three distinct streams flowed from
as many vents, one flowing northward to the base
of Mauna Kea, a second flowing southwark into
Kau, and the third, and by far the largest, fl w
ing first northward then DETECTING eastward until
II came within half a mile of HIlo. This latter
stream was about fifty miles in length and varied
in width from half a mile to two miles. The ap-
pearances presented at this point | shall describe
at u future time. 1t may be sufficient to state
here that n series Of parallel assures pointing
from the summit toward the base of the noun
tain gave issue to the lavas. No cone vas built,
and there Is no accumulation whatsoever of lrag-
mental eruptivc products.
was deeply impressed with the colossal char
acter OF the eruptions Of Muuna Loa. or the
e~ruptiOns which bear historic date, that of 1855
appears to have been the grandest. 1t would
almost have built Vesuvius. The accounts given
To me by many eye-witnesses OF these eruptIOns
recite observations which strike me as the most
extraordinary, though | cannot Tor a moment
question the general truth!ulhess OF these ac-
counts attested by SO many intelligent and credI-
sic witnesses. The general version is that they
breai: out suddenly and without warning, and
that the lava spOuts upward in enormous iOup-
taius to n great altitude, which the various OBJ
servers estimate all tic way from 500 70 1000
feet. How much of this may DC attributed to in
candescent steam and how much to optical Illus
ion Of one kind or another it is impossible to say.
But | cannot doubt the general testimony that
these vast lava fountains do spout upward To "a
very considerable height, and that The fires which
are actually seen are mostly lavas. | think there
is substantial evidence of this IN the appearances
presented at the sources OF the great eruptlons OF
1855, SO and 'GS. DR.. Coan visited the source
Of the eruption of 1855 while it was still active
and about three months before his death | had
the privilege Of inquiring OF him very particularly
about this matter, and his account substantiates
the general testimony.
One OF the pOst striking features of Mauna
LOa is the almost total absence of cinder cones.
There are n few small piles of fragmental material
here and there, but they are mere apologies for
cinder cones and are very aberrant in their modes
Of aggregation and in the character Of component
materials. Considering the portentious nature