Weekly national intelligencer., 1851-01-11
AGRICULTURAL GEOLOGY-No. XVIII.
BIZ JosJAH HoL sRoOK. ....
zon THE NATIONAL 1NpELLIsssssR.

.. 7oR THE NATIONAL IspELLIGssssR.
Magnesia is akaliae EARTH is less abunGun as an
element Of rocks and so and less active cherca agent
than lime. II is, however, extensively difsed in mineral
formations, and performs important agsaeies for the purposes
Of agriculture the mechanic ats, domestic economy and
health does not like ime constiaae the only or princi-
pal material of mountain ranges and rocky assss but forms
part of rocky and mountain rmasns both abundant and
widespread Magnetism Limestone is very abundant Of
large and extensive dsposes Of lime rocks magnesa
is considerable part h,se indeed for the convenience
Of farmers Of architects large quantity of msguesa
napairs the fertility Of SOILS II also ren5ers rocks fiabe
easily crumblng to sand Lime formations containing large
portion Of msgnesa called .olomie In the domole is
frequently found emoite, in The form of crystals in con-
siderable variety These crystals sometimes needle
fhrous running from centres in rays They hence
called radiated uemohte They frequently small plates
tables, when they called tabular emose Both the
fbrous and the tabular crystal Of remoe are commonly
white, yeowish white, frequently with CLASSY surface
differing greatly n their structure and general appearance
Together they furnish agreeable variety for csbinet
They quite attractive to the eye and tho needle shaped
crystals frequently have rather too strong attraction for the
fingers assuming the character Of country cousin s,ayn
longer than they wanted.
Magnesa enters very largely into the serpentine and SOAP
stone. The former appears in ridges often 10 noun
euptions hundreds Of miles. Sepenine ridges and rocks
found in Vermont, Massachusetts, New York New Jer
Pennsylvania, Maryland virsnia and still aher south,
in continuous range except frequently disappearing or
not coming to the surface This rock 10 named from i,s
varied coors, resembling the serpent though green predom
Mates harder than the sulphse Of lime (gypsum and
less hard than the carbonate, Common limestone II gives
readily to the knife, but not to the thumb nail
Two varieties Of serpenne somewhat abundant-the
common and precious The latter far less abundant than
the former The precious serpentne receives beautiful
polish is hence wrought into letter stamps nkstands
urns butter plates, and other ornamental FORMS 1t is also
extensively dused through Marbles giving them an exceed
lnsy beautiful appearance Marbles thus beauted by SER
pentine, bear the name Of "pd antique or ancient green
variety Of crystals and other beautiful minerals cabne,
specimens are found deposited in serpentine
ExPERINESr.-Not long since Washington school sent
20 the New York schools about hundred specimens of
drawing and writing In less than week after they were
more than thousand specimens by
'ne receivers in return for their gift Within six months
past the pupils of school in New York. Public School
NO have sent to Washington than thousand spec
mems Of their work. which have been distributed principally
oy Government. unconarcs to all parts our country and
to many parts Of other countries.