The Hawaiian gazette., 1896-06-16

ern Molokai. with or without islets
10 the shore and elevated not more thar
I've or ten feet are there old submarine
formations Besides. neither atnos-
( pherie erosion nor the action of ocean
waves ever slice OF land so exactly on
right line.
Prof Dana's explanation has received
wide acceptance. He believed that this
\ precipice vas part OF the wall OF vast
ealdera- the supplementary portion OF
which has disappeared by some tremen-
dous catastrophe He points out the
significant fact that the inclination of
the lava strata in the precipiee is to-
wards the Kona side OF the island.
showing that the center of the noun
tain must have been originally over the
region where the great caldera formed.
What / believe-to be the true expla-
nation I viii give you directly:
To complete the outline account OF
Oahu. must add that in comparatively
recent times its extent has been not
ably increased by emergence from the
sea Of considerable area Of what was
formerly coral reef The Pearl Locks
consist Of group OF deep. bzoad chan
nels in the old reef. that raarked the
course OF fresh water currents. The
surrounding low level land is simply
the elevated coral reef
The most notable feature, however.
in the Photography of Oahu is the
presence. al the base Of the extinct and
greatly eroded old VOLCANOES. OF q num-
her OF recent volcanic cones. In the
Immediate vicinity OF Honolulu you will
find. side BY side with the lodges of
ancient lava everywhere conspicuous
in the valley sides. einder cones with
scoria and lspiIH, almost as fresh look
ing as you would find at KiIauea The
town IS overlooked By the great tufa
cones. Punchbovi and Diamond Head,
while Telegraph Eli. close TO the lat
ter. Is typical lava cone in miniature
The three eonieal hills which form the
pleasing background o. the landscape,
grouped = tkey are about the deep
wooded valleys OF Makiki-a typical
valley Of erosion-are high piles OF
Iapilli. telling of stupendous explosive
eTuptions which sifted over the whole
land the material from which its deep
sich soil has been formed
/ have passed now in hasty review
the principal islands OF the Hawaiian
group. except Kauai, OF which / need
only say that il Is the oldest island OF
All, presenting no features Of unique
interest
Nov viii You follow me as III 10
picture the beginning OF volcanic
isIandz If you viii. believe you viii
Be rewarded by finding The explanation
OF some OF the most striking features
in the photography Of the islands.
have tried 10 describe
4 submarine ridge in the deep ocean
can hardly Be anything but the crest Of
q fold or wrinkle OF the earth's crust !
As the force that produced II continues
TO act it's materials are placed under |
greater and greater stress until rs I
sure at last opens TO emit molten rock /
squeezed up from beneath
am now concerned with the cause
or the mechanism OF the eruption We
have the fact that lava finds issue down
there at z depth OF three thousand 1
fathons, to meet under enormous pres
sure water almost freezing cold II Is !
evident that, # the lava Is not in vert
large quantity. II VIII become 50
quickly cooled that il cannot flow far
The superhezted steam which must
form EflI indeed penetrate its sub
stance and reduce its melting point 20
that It vfll creep further than It other
wise could down that slope Of low
gradient; but zfrer all It must harden
very quickly. and 80 become piled up I
IN cone much sleeper than would be
possible On land Fig -
OF course tbs emission Of lava would
be intermittent, and in the intervals
between the er1pfions or outfcws the
old vents would become 20 sealed By
the chilling Of the lava that naB lateral
vents wsuid Be the rule. 90 that the
mountain would gain IN
brss1th Of base. although It would be +
builf always With vsEy stesp sidss The