New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1849-02-09
chemistry In its Relation TO Agriculture,
DR.. ASTisELL's rTrH LECTURE

DR.. ASTisELL's NTH LECTURE
DR.. Asrl.ELLs Fifth Lecture. on Tuesday eve.
ming was devoted to mastery exposition Of the con.
slitueni, forming the Surface 81 ne Go5sor the Rock
Basis Of the Earth
The Crystalline and sedinenisry Rocks observed
Dr. A. are the two great natural divisions Of tn earth
crust The sedmeniary are those deposited out OF
water and It s vel 10 undertisnd how i g that rocks
ean be 80 deposited from liquids and If such causes I'll
elost-To this end, the Dr. went irto detailed expls
nation, not only Of tie possibility If s belns do1e bu.
the probability Of the same circums,srces having gone
On from an immensely remote period. Every shower
brings down and deposits more OF less OF solid sub
stances. and IN time ihick muddy deposit l. thus
formed, which nlaly harden and - pressure turns
y rock. All running waters in the same msuuer are
found - carry along with them great quantities OF
these solid matters The Nile = remarkable for this
the matters deposited By i upon is shores are fire.
quenhy Of the depth Of two inches this deposit be-
comes hardened and cracked Dy the heat II ihe SUP
and turns INTO 'old and tough entirely useless
70 the agrcuiturst if not indeed injurious 70 the sol
itself
ia calculated that the Rhine carries down 400 tons
daily Of these solid matters which l. deposits IL
mouth IL has also been ascertained that the quantity
OF sold matters deposited By the Gsnges n 40 900 900
Of tons day-an amount Of matter perfectly enormous
If we look 81 i ia detail but It s carried down By
great body VI water and "a found % settle upon the
oOttom Of the River.
There Is ia the Earth everywhere, a tendency 70
Equalization. We md that the higher portions OF the
esrths surface being gradually worn down 10 a
lover level while the matters thus carried OF con
veyed 70 the ocean and the re tend viii be 20
the formation Of other solid substances-or the strata
Of the earth Of the bottom Of the ocean.
SrGtoGit0n, then the formation Of rocks beneath
the ocean is going every day That this process u
IN active existence st 10 sbundsntly proved by the
experiments Of the Swedish Government, undertaken
at the suggestion Of VI Berzelus upon the shores Of
- I-a4 EaN4rY
ed every third year, for series Of ten years and t
found that elevation Of 80 inches occurred be-
tween the periods Of each observation-or 50 inches
elevation Ia the ten years. During al this time. the
proving that the changes 10 the land owing solely
. ne action and not AZ al attributable % any
PROGRESSION Of the such results and observations
then, render ne familiar with me great changes winch
have gone on 10 the primitive ages Of the world
Granite is generally looked upon the oasisrock OF
the Earths surface but although undoubtedly i is 90
We frequently ind Il upon the suriace-lIhis the DR.
illustrated BY diagram mountain of Granite whose
summit had been forced upward through everything
strata OF slate and clay. by some enormous Internal
pressure-very clearly explaining the cause OF the ire
Quent exposure Of a granite surface on the earth
Grpuiie contains only three minerals. OF these
lari- is the largest Ingredient Another Is Fcdspdr
and J, Is this which gives Importance 20 Granite for
agricultural purposes but renders such svsriey unit
for building purposes being liable 10 speedy affection
by the weather. and of easy decomposition. The third
mineral entering into the composition Of Granite is
Mica which 10 the most ndestructible Of the whole
hence il Is bad for the sgricultgrist
Mica consists OF the Slick which enters into the com
position Of the other ingredients OF Granite rocks
but also contains little Potash little Magnesa, and
large quantity Of Iron Regarding the formation q
Granite Dr. A. inclined 10 the opinion rapidly gain
ing ground that Il Is sedimeaaTy rocknOt Of gneous
constitution he illustrated this By reference % the
slow cooling and consequent capitalization Of the Lava
Of Mt Hecla In Iceland where for years after the sur
face has been thoroughly cooled the Interior OF The
still retains sufficient heat 10 produce combustion
There little doubt the rock found this
Island and IN its vicinity, il also OF sedimentsry iorms
ton.
Lying outside OF the Granite are rocks Of an entirely
different structure These generally termed slatcs,
and distinguished by ready cleavage hence their
name. There two kinds, known ~ mics-slate aud
clay ssteThe tine variety OF earth known As potters
porcelain clay is formed by the decomposition Of
the eldspsr contained IN the first OF these varieties
mica slate.
The composition OF Feldspsr Is slick potash and
slumins. II Is from two of these (sex and aumina-)
that the POrcelanclsy Is formed When the Feldspar
decOmposes the Potash IL washed out II carried into
the atmosphere and there mbibng the caroonic ac'o
always present IA the air forms carbonate OF potash
The carbonate thus formed finds lie way into the earth
aud is than taken up by the roots OF numerous plants
Trees likewise taking up through their roots II u car
red into the stem and forms one OF its constituent
parts We finally burn such trees 10 OOtsin the same
Potash for ordinary which we find was thus orsi
nsly formed by the decomposition of the FeldsPar.
Porcelain then, Il the combination OF the Otner two
constituents of the Fedspar left after the decOmposi
ton and separation OF its constituent Potash.
In the Sstes find the first traces OF animal or We
getsble life the globeA FOSSIL specimen OF Trio
bite found in the LOckport Slate, was exhibited BY Dr.
A. Il was save the loss Of the head Of the animal 10
an excellent state Of preservaton-Beside the Trio
bites we find also in the States numerous remains Of
different MOlluscOus animals.
The Old Red Sandstone and Limestone next super
vene deposits above those already mentioned Mar
be Is found 20 be nothing but Limestone which has
become somewhat distinct AS IL slowly formed, and
which from the peculiar circumstances IN which II was
placed, admits of Tine polish Chemically, there Il
found to be no difference between the Limestone and
the the Limestone are the Chalk an the
finer Claws 1t is between the strata Of Limestone that
the Coal Is found deposited 10 thin layers which run At
d slight angle downward. The DR.. here entered into
an explanation Of the vegetable nature of Coal, the
presence of trees both singy and In entire forests IN
the beds OF this substance, ec-5ut we must ioroear
farther report Of bis entertaining and admirably ar
ranged remsrks-our space being already oyerrun
The sixth Lecture, on Friday evening will treat
Of Soils as formed from Rocks their different Appear.
auces and their Chemical Constitution.