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

| plunt, and Is called the piulnula All seeds
have, the radicile and plumula, whether they
be mono coyledonuus asindian COMMUNICATING
other small grains and the whole family ofgrass
es; or whether they be di-cotylcdonous, as the
bean and the whole family OF Iegumenous veg
ctab!es; and the process of gernHnation is com
mon to the whole vegetable kingdom. A seet
is said to germinate, when it undergocs tia
change by which the radice is converted into
u root and grows downward into the earth, alic
the plumnla is"converted into the stem, enc
shoots upward, carrying along with it, in the
case Of the bean, the two cotylcdons, 'wLicl
are employed in giving nosiislrmcnt to tile in
FAINT plant, until, from the extension Of lis roots
and the heexpunsion.of its leaves, il is capable o.
receiving food from the soil and the atmosphere
LISA fact well established, that the clranges we
lave been describing never take place unless
moisture be present; that they never take place
unless The temperature be above zero, and that
some seeds will gcrlninaic in lower lempera'
lures than others; and that they never take place
unless atmospheric air or oxygen gas he present.
BOYLE, Boerhaavc andlluschenbroeE pruvcdby
repeated experiments, that seeds will not vese
tate in the vacuum OF an air pump; and schcclc
and Achard ascertancdb by similar experiments
that termination will not tske place in nitrogen
gas, hydrogen gas, or carbonic acid gas, ,.nnless
they arc ina state Of combination with oxygen.
Light is also said 10 have sensible influence
OH the geruinaIon Of seeds, tho TO what precise
extent, seems not 10 be well ascertained: il is
certain, however, that it retards the process, Ell
lhcr by some inherent property which it pos
sesscs or by indirect agency, in producing a
certain modification of heat and moisture I'm
favorable to vegetation.
Thus il appears that heat, moisture and oSy.
gen gas, are Indispensable to tho process of
examinations asst will hereafter be seen that
they are important agents in the further pro-
gress O! vegetation:
After the 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,
md it is obvious to the SENSES, that. the whole
plant.!rom lis rapid increase in bulk, is con-
stantly acquiring new accossions ofmater: aud
us this new matter cannot be produced by tile
plant itself, it follows that plants like animals,
| require food not only for their immediate nour-
isIlment, but also for the purpose of replacing
those particles of matter which, having become
nuiltcd fpr nutrinscnt, ere llrowa out by the
cxcrctory vessels.
II was for 4 long time lues;ionamong phys.
biologists, whether water did no, constitute the
only food necessary to the sustenance & growth
OF plants. This idea, which subsequent expert.
mcnts have proved 10 be erroneous, wasdoubt.
less suggested by the fact, that the elements or
component parts oiwatrr, namely, oxygen and
hydrogen, are uniformly found in the substance
Of plants; but tie experiments of Bergman and
Margrati, have forever exploded theory which
it would scem never conld have been seriously
advocated, except in The infancy of the sci,
ence. These philosophers proved that water
is a necessary agent in celebrating the ioud
of plants, and is the vehicle in which il is COLI
Quoted to the roots 10 be absorbed; and those
experiments which misIed Van Eelmonl, Bon
net, Boyle, Dullamel, Tillet 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 distilaion, it always holds in solution some
Of The elements which cilter into the substance
of vegetables. Without water, the seed
can neither gcrmlla,c nor the plant vcgetale,
but it no more follows that il constitutes even
the principal fond OF vegetables, than That
oxygen gas which is esscna! 10 animal life, is
the principal food of anirla!s.
We have already seen that mir is necessary
10 the process of vegcialinn; ard it has been
ascertained by the experiments Of Chemical
Philosophers, that large portion Of the car
bonaceous matter found 10 exist in plants, is
illbibed from the atmosphere. Three of the
constituent elements of atmospheric air, name
Iy, carbonc acid gas. oxygen, and moisture arc
said to furnish food TO The plant.
Another source from which vegetables de-
rive their rourislmcnt. is the soil (which they
grow, consisting Of salts, carlls and animal aud
vegetable substances i'll 4 stale Of decomposi-
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 arc oxygen, hydrogen, carbonic acid and
nitrogen, the lal,cr clement being discovered
only in few vegetables, ,whiIstit is always found
TO exist in the animal economy
Having seen that plants require food, and
that they derive it from the atmosphere, and
from the soil in which they grow; itremains 10
enquire how the foud is received; in what form
i, is received; ard what chemical changes it
4 e., ,t,to bo