The daily morning journal and courier., 1906-10-25
EARTHQUAKE.
Readjustments of Weight That Alter
 the Flexible Earth Crust.

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 mountain chains, the rocks are seen tC have been thrown into arches an,
 troughs and even to have been crum.
 pied and folded like sheets of paper ol
 dislocated or broken up by the enor
 nous strains and stresses they have been subjected to. These are the strikes, dips, synclinals and anticlinals
 faults, folds, upthrows and downthrows of geologists, modest examples of
 which can be seen anywhere in cliffs and even in quarries and railway cut tings
 Of the conditions prevailing beneath
 the crust we know far less. When pits are sunk the temperature increases at q progressive rate with the depth. boil. ing springs are encountered, some making their way to the surface, red hot stones and ash and molten rock arc violently exeruded through vents, but most significant of all to the geologist is the metamorphism of rocks, which must have been melted at relatively moderate depths, but are now exposed on the surface in every quarter of the globe. There is thus the certainty that the cooled surface is underlain at some not altogether inaccessible depth by rock in molten state, both fluids and pasty, through heat Below this is the intensely heated solid sphere, to which astronomers assign the rigldity and density of steel and which is kept solid by compression of the external layers. Between the superheated nucleus, kept solid by compression, and the cool en- veloping she'll in which lies the com pressing force, some intermediate con dition must exist, With lessening pres sure nearer the surface normal condi- lions must prevail, and rocks at their melting temperature must be in the li- quid state of slag from smelling fur mace.
 Our globe would therefore consist of an outer cooled heterogeneous and feX- ible crust, with temperature increas- ing downward and passing into rocks at and above the melting point in a li- quid state, which in turn overlie the heated nucleus, kept solid by compress sion and of the rigidity of steel
 If the crust were undisturbed the molten layer upon which it rests would be inactive; but atmospheric agencies, frost and rain, are ceaselessly at work transporting weight from the hills and depositing it under the sea, decreasing the pressure here and adding to it there The rivers debouch into the sea charged with silt, which is eventually deposited outside the influence of the surf, and the breakers acting like a rasp along the base of the cliffs contri- bute their quota of sediment, eroding and breaking up the coast, the material being carried by the waves to swell the deposits forming parallel to the shore within the littoral zone Geology re- veals that these deposits may in time reach thousands of feet in thickness. Simultaneously the removal of weight by the breakers irnpairs the resisting power of the crust along the actual sea margin. Thus two parallel lines are continually forming, the one of inereas- ing pressure and the other of decreas- Ing resistance.
 Is the crust so flexible as to be sen sible to such readjustments of weight In a past age when perhaps man was already among It's inhabitants the earth suffered in places from a glacial period, when vast ice caps formed over the elevated regions, Under ere of these accumulations the whole of Wales sank beneath the sea level. ris- ing again to it's existing height as the ice melted away. In hotter regions masses of coral are forming reefs and atolls, rising In some cases from water hundreds of fathoms deep. The polypes forming the coral can only live in surf near the surface, and unless subsistence had continuously kept pace with depo- sition no such masses could have been formed. Many of the great rivers emp ty into bays sheltered from coast cur- rents and there form deltas which hava been proved by borings to De thousands of feet thick, yet each foot has been formed in water a few feet deep, as proved by the angle or bedding, the fauna, drifted land debris and the suit- ing action of the waves. h all these cases the crust must have sagged un- der the increasing load of added mate rial, and did it not similarly give way under the additions of we Sht along the literal zone every lslan4 and continent would be SUIT 'unlel for miles by shoals no deeper than the disturbing motion of the waves. When the crust sags out to sea the ,olu,nn n: water over it dee jens, at2r. aI'irg the pjas- sure. The pressure acting on the mol ten layer tends to squeeze 1t, not sea- ward where the water is deeper, but toward the shore where a line of least resistance is already prepared by the breakers.
 The effect of steadily increasing lat eral pressure acting on a long and re- latively weak shore line of heterogene- ous materials must be extremely com plex. The molten matter is able to eat it's way upward like a corrosive fluid melting the rocks it successively comes in contact with, until it finds relief in pouring out lava in streams of appall- ing magnitude. This was the fate of the seaboard of the northeast Atlantic in tertiary times, remains of these eruptions existing in the masses of ba- saltic trap rock in Antrim, the He- brides, Faroes, Iceland, Spitzbergen and Greenland. But where the super incumbent strata are still thick and massive, and especially where they have been already arched into lines of hills, as, judging by the watershed, must have been the case along the Pa eific coast of America, the molten mat ter would continually and irresistibly force the crust upward, producing a