The sun. [volume] (New York [N.Y.]) 1833-1916, 1915-03-21
SOME NEW BOOKS.
The Mystery Of the volcano.

UP ATlSlnS " 1edt1eT OF VapOr WHICH
may at times through peaceful air
spread out in the upper heavens in
tho semblance Of a pine tree. This is
TIE Vesuvius type, more perfectly
~ esented in Mayor of the Philippines.
although the latter is less familiar in
pictorial representation. This type is
the least frequent of all volcanic vents,
though made more familiar because
of its picturesque value. Nor is the
outer guise OF the volcanic mountains
the only point as to which common
information is misleading. The whole
subject OF the physics OF this mani
festation OF plastic ea-h material Is
as yet imperfectly determined. Many
theories have been proposed and
argued with great skill. yet each Is
complicated with phenomena not yet
applicable in terms Of the theory. and
no matter how cogent the theory may
appear. each is entanRled with a mass
OF insupcrable objections.
No little industry has been expended
upon tho study of volcanoes; ut several
OF tho more important cones observa-
tories have been established for the
systematic daily record OF lava con-
ditions. The solution OF the problem
has not yet been reached. but knowl-
edge based upon accurate observation
has now arrived at the point where it
is possible TO set forth the terms of
the problem, the constant factors
whose explanation appears now to be
established, the discordant elements
-t.--- ..zf,sNsAsN at NAnaAtnG for study
This IL the aim of the Silllman lee
lures delivered last winter at Yale by
DIR. JOSEPH Z. IDprNGs and now pub
lished under the title The Problem Of
Volcdnism yale University Press,
New Haven.
At the outset the problem ot the
volcano seems remarkably simple.
The vesuvius or Mayor type repre-
sents II at it's lowest terms. Above
the mean surface of the earth there
is a more or less regular cone o.
earth matter which may range all the
way from light ashes through the
scarcely more ponderous yet moro
compacted pumice to solid lavas n
obsidians to the heavy basalts and
dlofitcs. This CONF is the solid REM
nant OF the material which has been
eXtruded from below at the tempera-
ture OF liquefaction. has ooled in
contact with the atmosphere and has
taken on ono of several solid forms.
Sustained by the exterior cone Is com
monty a lake of fluid matter which re-
mains molten so long as its supply of
heat Is restored from the original
source. which tends to become solid
by cooling from tho atmosphere and
from the surrounding rock mass,
which It other times is subjected 20
asst prcssures which tend 10 dis
charge the molten iaVas he! oud the
rome in comminuted form rs dis
charges OF ash and scoria ar with less
violence as floods Of lava passing
ovcr thc'rim Of the crater ar break
ing down the crater wall at some
point whore the Solidity and COM
,inuity If tho retaining mass proves
less thar tho weight and cNpulsiV,
force acting against this purely tenn
porary dykn Below this fire lake We
infer the eXistehc. of q duet COM
municating downward through the
rock formations AMI serving ~ Il con-
6uit through which the molten ma
terial j. brought To the poiu; uf lis
charge this duct Is not wholly -
matter Of Inference. In the crater ~
Ki'auea. ;hc flank crater Of Mduna
T.oa. il has been possible at rare IN
tervals to observe the fir. pit. Hale
maumau. completely empty and To- DIS
cover through HE SwiriinE Vapors ~.
entrance of what seems TO h the duct
from below.
This duct is the important uhicc. oi
study. yet IN the nature Of things q
is the least open to examination. To
cone may he irregular or wholly alb
sent. as in tho case Of Kiiauea: 'ns
fire pit is necessarily more constant,
vet II NAY he reduced to very SINAI
proportions. as was noted IN Amhrym
before the eruption of 1913: the duct
however. is an absolute essential e
every volcano, the channel through
which molten earth matter ono
from somewhere below the surface
The outer end of every such duct
IL discoverable. it discovers itself >,
the ~fervent heat NJ IT'S discharge o'
fuid matter. Its lower and inner clt
passes all comprehension. We do moi
know how far il extends into ~
through the crust OF the earth. W-
do not know how il has been formed
we are left without q sure guide in ;
realm where all is speculation. At tn,
outer end of the duct We find miuera
matter nuid by reason of neat and as
Stunning an amorphous solidity afto'
that heat has been radiated away. an.
this MUD mineral matter Is undol
varying degrees of pressure sunicicn.
to overcome the pressure of gravity
and the pressure of the atmoSpher'
and 10 protrudc the flowing matte
against the combined force Of theS.
and other ~resistances.
The central problem Of volcanisn
IL TO discover the source Of this fu''
mineral matter which flows upwar'
through the duct, to account for N
enormous pressure which actlates II
The simplest suggestion IL hat tn
duct extends through the cooled crls
Of the earth and taps the Hypothetical
molten core Of the globe ASSUMING
the existence of this motion core an,
the duct which taps II, there remain
the secondary problem Of tho Sourc
OF the pressure. This line Of though
takes us away from the Present stat
OF the earth and into the realm o
cosmic physics. for "" must beei'
with a better comprehension of tn
formative stage of the earth WhlC'
has resulted in the globe which i no'
habitablc,
Accordingly, DR.. lddtnss begins hi
49,