The New Orleans crescent. [volume] (New Orleans, La.) 1866-1869, 1868-11-28

part fipde its way to the bottom OF the deep seas
small proportion only may be brought by som
regularity in the distribution Of ocean currents
or 10 the progress of the tidal wave) to aid in th
fore, such shoals and banks may be, the large
mutt, we suppose, be the amount OF land whic
l. washed away never to reappear. And a
though banks and shoals of this sort grow yea
by year larger and larger. yet they confirm
Always (unless added to srti6cislly) either beneat
the sur ace Of the natter, In the case of shoals O
but very slightly raised above the surface. Now
| if We suppose the destruction Of land to proceet
unchecked, 1t is manifest that at some period
4 however remote, the formation Of shoals ant
banks must come to An end. owing to the con
| tinual diminuton of the land from the demo
| lition Of which they derive their substance
| In the mean time, the bed OF the sea would
be continually filling mp, the level of tbs
| sea would be continually rising, and thus the
banks would either be wholly submerged through
the effect Of this alone, or they would have
SO slight an elevation above the sealevel that they
would offer little resistance TO the destructive
effects OF the sea, which would now have no other
and to act upon.
But we have yet to consider the second princi
pal cause Of the wasting away of the land. The
cause we have just been dealing with acts upon
the shores or outlines of islands and continents
the one we have now to consider acts upon their
interior. 1t will. perhaps, hardly be supposed
that the fall Of the rain upon the land could have
any apprecisble influence in the demolition OF
continents; but, as matter Of fact. there are
ascribe more importance The verv fect 49,
enormous deltas have been formed az the
mouths OF many rivers-ssn otter words the actual
growth OF continents through the effects iof rain
fal-is proof how largely this cause must tend
to destroy and dsintegrate the interiors Of our
ell presepts the following remarkshIa ;IInstrat
"During q tour IN Spain,'' no writes, al was sur.
prised to district of gently undulating ground
In Catalonia, consisting of red and grav sandstone
and in some parts of red mari. almost entirely d.
nuded of heritage; while the roots of the pines
helm oaks, and some other trees. were half ex.
posed as IL the soil had been washed awav nv
flood. Such ia the state of the forest. for exam.
pie, between Oristo and Vich and near San Ia.
renzo. But, being oyertaken by a violent thun.
derstorm 10 the month of August. I saw the whole
surface even the highest lie yels of some attopped
hills, streaming with mud, while on every declivi.
~ the devastation of torrents was terrific. The
pecuarities in the physiognomy of the district
were at once explained and was taught that in
speculsting on the greater effects which the al.
rect action of rain NAV once have produced on the
surface of certain parts of England. we need NOT
revert to periods when the heat of the climate was
tropical"
the shores of continents. and of the action
of rain upon their interior. and remember.
ing that unless the process of demolition
were checked in some way, each cause would
act IICm year 10 year with new fOrCe-OQe
through the effects Of the gradual rise of the
ca bed and the other thronoh tba eff.cts
of the Gradual increase of the sn5faca Of ocsan
exposed to the vsporizIng action of the snn which
increase vould necessar;lv incraasa ,ha nnan.,.
of rain yearly precinitated On the land We 10y
the Justice of the opinion Expressed nv Sir Joho
HerscbeI that chad The nrimevai yorId 49,
constructed as II now exists. time ennneh has
elapsed. and force enonoh directed 10 tsst anS
has been in ACTIVITY 70 have Ionn &c ass,ro.nS
eyery yestipe of land y ." N'''''0u
We see. then. the necessity that exists for The
action of acme restorative or nraserys,;va foroe
sufficient 10 coupteract the efec.s of the cont;nn
GUS processes of destruction we have indicated
above. If we consider. we shall see that the AZ.
siructiye forces owe their efciencv 20 t,a;r IraJ
ling action that ia 10 their Influence In radnc;na
The solid part of the earth IN the 6opre of nae
fect sphere; therefore the form of force which Il
required to counterfeit them ia one that shall tend
TO produce irregularities in the 'conto, os
The earth. And IL will be remarked that al.
though upheayal ia the nrocess which on
pears at first sight 10 ba the onlv eg,c,pp
Al remedy 10 the Ieyelling action NJ rains and
ocean currents, yet the forcible depression of the
ssrih's surface NAV. proye in many instancss No,
more effective. since il NAV serve N reSncs ,bs
,ea. level in other nlaces 'NNN' VIZ
Now, the earth's subterranean forca. sa,vo %
produce the very effects w hch are roon;.as =;
u der to counterfeit the continual dsinteqraton Of
he shores and interior narts Of cnn,;nea,s S VI
q the first Mace their sction IA M, d;s,r;br,aj
With anv approacb 10 nniformi,v ovar S;soso..
,aris of .se eurth.. crust. and tnererore e,1.
igure they tend to give TO the surface of thar
rust is not that of perfect sphere. This. of
tself, secures the uprising of some parts of the
old earth above the sea.leyeI. But this ia NOT
u. On a comparison of the various effects dine |
o the action of subterranean forces. IL has been |
ound that the forces of upheavai act. on the |
Ehole, more powerfully under Continents. and |
specially under the shore-Iines of contioents |
'hile the forces of depression act most power.
uly, on the whole, under the bed of the ocean.
t need hardly be said that whenever the
srth is upheaved in one part. IL mnst he de-.
ressed some where else Not necessarily AT the
anne instant, it should be remarked. The pro.
ess of upheaval may be either momentsri.
accompanied by a corresponding process Of da.
ression, or the latter process NAV take Mace bv
gradual action of the elastic powers of the
srth's crust but in one way or the other. the
aance between upheaval and depression must
e restored. Hence il IL can be shown that for
lie most part the forces of upheayal act unaer.
cath the land, it follows-though we NAV mot he
Bile TO recognize the fact by obvious visible
gns-that processes of depression are taking
ace underneath the ocean. Now. active vol.
noes mark the center of q district of upheaval
I'd nearly all volcanoes are found near The sea
seems as If nature had provided agai,at the IN |