Edgefield advertiser. [volume] (Edgefield, S.C.) 1836-current, 1840-06-18

| piuul, ana Is called Tie piulnuld. au seeos
have. the radicie and plumula, whether they
beinono coty tyledonous, as indian corn fwheatand
other small grains and the whole family grass
es; or whether they be di-colylcdonous, as the
bean and the whole family oiIcgumenous veg.
ctab!es; and the process Of termination is com
mon to the whole vegetable kingdom. A seed
is said to germinate, when it undergoes tlIa
change by which the radiclc is converted inlc
root and grows downward into the earth, and
the plumHIa is~converted into the stem, and
shoots upward, carrying along with it, in the
case Of the bean, the two cotyledons, which
are employed in giving nosiishmcut to tile in
fant plant, until, from the extension of lis roots
and the.expunsion.of leaves, II is capable oi
receiving food from the soil and the atmosphere.
lisa fact well established that the changes we
have been describing never take place unless
moisture be present; that they never take place
unless the temperature be above zero, and thai
some seeds will gcrmnale in lower tempera'
lures than others; and That they never take place
unless atmospheric air or oxygen gas he present.
Boyle Bocrhaavc andAluschenbroek provcdby
repeated experiments, that seeds will not vese
tate in the vacuum of an air pump; and schcclc
and Achard ascertaincd by similar experiments
that germinaton will not tske place in nitrogen
gas, hydrogen gas, or carbonic acid gas, ,.nllless
they arc ina state of combination with oxygen.
Light is also said 10 have 4 sensible influence
on The termination OF seeds, tho 10 what precise
extent, seems not 10 be well asceriained: ii is
certain, however that i, retards the process, Ell
,Ler by some inherent property which 1t pos
sesses, or by indirect agency, in producing
certain modification Of heat and moisture I'M
favorable TO vegetation.
Thus ii appears that heat, moisture and oSy
gen gas, are indispensable to the process Of
germinaion; rs il will hereafter be seen that
they are important agents in the further pro-
gress o! vcgctalion:
Ahertlc process Of termination is completed
the plant, under favorable circumstances, con-
tinucs to grow; its roots are increased in num-
ber and size; lis branches multiply and expand,
and it is obvious to the senses, that! the whole
plant.!roE lis rapid increase i'll bulk, is con-
stan,y acquiring new accessions ofmaltcr: aud
us this new matter cannot be produced hy the
plant ITSELF it follows that plants like animals,
require food not only for their immediate nour-
sI,mcnt, but also for the purpose of replacing
those particles of matter which, having become
untitled far nu,rimcnt, ere lhrowA out by the
excretory vessels.
II was for 4 long time qles:ionamong phys
biologists, whether wafer did not constitute the
only food necessary to the susienance & growth
Of fplanis. This idea, which subsequent expert
mcnts have proved TO be erroneous, wasdoubt-
less suggested by the fact, that the elements or
component parts ofwatrr, namely, oxygen and
hydrogen, are uniformly found in the substance
Of plants; but the experiments of Bergman and
Margrati, have forever exploded theory, which
il would SEEM never could have been seriously
advocated, except in The infancy of tile SCI
encc. These philosophers proved that water
is u necessary agent in celebrating the food
of plants, and is the vehicle in which il is COLI
Quoted to the roots 10 be ahsorbedi and those
experiments which misled Van lIelmont, Bon
net, Boyle, Duhamcl, Tillct and others. into
the suppos,ion that water is the sole and prop
er food Of plants, were made without due re-
gard TO The fact that. unless il has been purified
by dis,iIaion, it always holds in solution some
Of the elements which enter into the substance
OF vegetables. Withcut water. the seed
can neither gcrmlla,e nor the plant vcgetate,
but it no more follows that it constitutes even
the principal iond Of vegetables, than That
oxygen gas which is essential 10 uniinal life, is
the principal food of anirlas.
We have already seen that mir is necessary
10 the process Of vegetation; and it has been
ascertained by the experiments Of Chemical
Philosophers, that Il large portion Of the car
bonaceous matter found 10 exist in plants, is
iubibed from the atmosphere. Three of the
constituent elements of atmospheric air, name-
ly, carbonc acid gas. oxygen, aud moisture, are
said 10 furnish food to the plant.
Another source from Which vegetables de-
rive their rourishmcnt, is the soil i'll which they
grow, consisting Of salts, carths, and animal and
vegetable substances in stale of deconpos-
ton. 1t has been well ascertained by chemical
analysis, that the same clements that enter into
the substance Of the plant, are also found 10 be
the principal componcnts of animal substances:
these are oxygen, hydrogen, carbonic acid and
nitrogen, the Inter clement being discovered
only in few vegetables, ,whilstitis always found
to exist in the animal economy
Having seen that plants require food, and
that they derive it from the atmosphere, aud
from the soil in which they grow; itremains 10
enquire how the foud is received; in wha, form