Daily capital journal. (Salem, Oregon) 1903-1919, 1905-12-14
SOLVING
MYSTERY
OF CORAL
tBy Andrew wHsonJ

ing the history Of coral reefs. II was
in 1912 that the great naturalist gave
to The world his reading Of the story
Of the corals. Prior to that date no.
body had successfully ventured on the
solution Of a complex puzzle connected
with the erection Of the reefs. Brief.
ly stated, this problem had reference
to tho depth at which a coral could
live and could build mp "the impcr
ishable masonry Of the sea. Everybody
had agreed then, as they agree now,
that the reef building corals cannot
live In deep water They demand light
and they require oxygen in plenty, and
these items Of life are only 10 be had
relatively near the surface. A depth
Of $50 feet is given az the maximum
limit Of the corals Below this only
dead and gone corals are to be found.
This is the stable preliminary fact
which starts a long and interesting
controversy, TO tho calculation or set
tlement Of which recent details must
bo regarded ~ having contributed In
highly remarkable fashion.
Tho question, "How, II coral can
not live below 100 feet In the sea, arc
reefs which rise In oceans miles deep
orcctd1" sums up the essence Of the
coral problem. II was 10 this question
that Darwin framed tho 6rst philosoph
ic reply. to took as tho keynote Of
his thcory-framed on facts observed
by him during hia voyages-the sink
Ing Of land This last ia, Of course,
% familiar and constant feature Of tht
earth. Land rises aud land sinks as
part and parcel Of tho cosmical schcms
Large tracts have been submerged. just
as rocks formed on tho sea bed have
been elevated and added 90 tho upper
crust Of tho globe. Darwin, discard
ing tho notion that submarine hills or
elevations formed foundations for cor
al building, lod us 90 see that tho pol
ypos began their work on tho shores
OF ordinary land. Here they made, az
their own depth,.a fringing reef. AZ
long az this remained stationary no
great change happened 10 the reef. IL
could not Increase out Of tho water,
and Il could not increase dowRwarda
below the limit Of coral depth.
Suppose, however, tho land or island
began 20 sink, then fresh bases would
be presented for coral growth. The
lowest eorals, carried beyond their
depth, would diet the uppormost ones
would continue 90 grow, this inehease
keeping pace with the slow subsideneo
OF tho reef. In due season a second
Kind Of reef would be formed on the
foundation Of tho FIRST. This is tho
barrier reef which Is separated from
the land by belt Of water, II Is be'
cause tho coral grows fastest on the
sea face Of the reef. while the inside
eorals die, that a channel Is natur'
ally formed between reef and land.
Finally, said Darwin, suppose that the
land subsidenee continues, and suppose
that the original island completely dis
appears, then around the old land We
shal have produced a great coral cup
the edge or rim OF which appears at
the surface Of the ocean as the per
feet coral reef or atOll, inclosing a
sheet OF water termd lagoon. The
size and shape OF the coral ring will
depend on the size and shape Of the
original land.
A more recent theory maintains that
atolls may be built up on volcanic for
nations arising from the sea depths
and brought up 10 the coral limit Of
life through the deposition on them
Of chalk animaleules and the like, The
particular shape Of the atOl, it is con
tended here would be due to a kind Of
wasting process going on in the coral
mass whereby through chemical ae'
tion, the central part would be eaten
away leaving the coral growth active
at the edge Such mode Of atoll for
nation Of "faiTy wings" in grass. In
this second theory no need is exper-
fenced for land subsistence, so that il
is battle to the death, in a sense
which is waged between the opposing
views
Darwin often expressed the wish that
some one would bore down into the
rim Of an atoll, and subject the bore to
termination by way Of aseertaining
whether his views were correct or not
ESbdently, if such boring were made
the question would be settled either
by finding a tremendous thickness Of
Ia,waN k,.fHA ~, 81. A. ,i-fr.t,,T