Nebraska advertiser., 1862-10-25
Circulation OF the San.

The last number of the Gardeners g
Monthly contains very interesting ar
ticle from Yardley Taylor on the CIR
culatiOn of the Say from which we make
the following extract:
"The theory of q downward flow of
sap, as supposed by the first writer's on
vegetable physiology, is giving way, and
the writer's Of the present day assert that
there is no such flow. (See arncle Bot
any in the New American Encyclope-
dia. Theoretical writers. or those who
copy from former ones. often advanced
the same theory; while practical men,
who base iheir theories upon their obser-
vations Of nature, reject it. Nurserymen
who practice grating, know that success
can be had by inserting the graft so that
the inner bark of the graft of the stock
shall be in contact, so as 10 admit of the
sap from between the bark and the wood
passing upward itto the graft between its
! bark and wood. There can be no other
way for growth, as the grandles of new
wood only form between the bark and
sap-wOOd, no where else, and this mate.
rial for growth must come from below
for there are no leaves above to prepare
the matter for assimilation, as the down.
ward theory supposeS. Budding, as
praeliced by nurserymen, is equally con-
elusive; there the bud only rests upon
the sap-wood beneath the bark, and IN
no contact with the pores of the wood at
ALL only with the pores between the bark
and wood and ii the top of The stalk is
cut off, as is usual, it grows at ouce,
though there is no part above from which
a downward flow can come. Many more
facts might be mentioned, all le aiding TO
the same conclusion, but these, so well
known to all who are acquainted with
grating or budding, may suffice; indeed,
the evidence appears to me ID be so con
elusive, that can see no reason whatever
for downward flow. Ii appears to me
10 re 100 much of roundabout way to
attain an object, to be consistent with what
We know of the simplicity of natures
laws; they are always direct and TO be
admired for their simplicity.
''lf, then, there is TAO downward circu-
la,ion, as | confidently believe there Is
not, the question recurS, what's the true
theory of the circulation of the sap?'-
This, to my mlnd is very simple and
plain; whether | can make it appear
plain to others, remains to be seen. Let
US recur II facts generally admitted. and
base our theory there. All writers on
vegetable physiology, believe, admit that
water from rain aud snow containing
matters for growth is iinbibed by the
roots, principally by the spongloles or
small rootletts, though | have httle doubt
that even the large roo;s imbibe some, as
there bark is spongy. Among these mat
ters, cabonlc acId gas is prominent, and
it is generally believed thai portion of
this gas is Imbibed by the leaves. This
gas is considered the only source from
which the carbon of the plant can be de-
rived. Carton, we know, is deposited in
growth, and chemists tell us that oxygen
Is given off in the daytime. Other mat
tiers, as potash, &C., are believed TO be
carried INTO the plant IN the same way /;
of these facts there is hlIle dispute.
"Caruon acid gas, however, must be
ldecomposed, and we know that il Is, but
by what means, there Is diff renee of
opinion. Sunlight has been considered
the agent of thus decomposition, but OF
this there may be doubts. II there Is nc
downward circulation, the gas can not be
! oo L. hxy,
supposed. FVsther, we have no other
evidence, than this suppOsltion, that sun
! light can decOupose carbonIc gas al all !;
nothing in my reading of chemistry would
encourage the conclusion that sunlight caI
r~lease oxygen from its compound. Sumt
other agent then must be sought for, aid
we have one IN electrRity, that we know
: eau effecl this decomposition.
THE beautiful art of electrolyping is
evidence of this fact. Here metal is dis.
solved by acid, making a compound OF
oxygen and metal dissolved in water, by
. The application of galvanIsm, which Is
? only another form OF electricity; the OK
xgen is given off, and the metal is depos.
tied in It's cwn form again. If electricity
can release oxygen from this compound
4 why may it not from all us compounds
: Oxygen is negative, while carbon aIlC
|, metals are positive. This presumpuot
has much stronger grounds for lis toua
n datiOn, than that for the effects chargea
4 ble TO sunlight.
Il ELECTRICITY has been proven 10 greatly
facilitate vegetable growth. If We erec
! wires, say ten or fifteen !eel hi5n, IN al
; open space, and pass them beneath The
soil where vegetables are growing, thest
vegetables near and above these wIre,
a will be larger than those alta distance
/ Here the eleetFlcity eau add nothing o.
itself to the plants; II must act by lndu
cling greater activity III some prInciple o
\ growth. and what principle can that be
other than the decomposition of the car
bonic acid in the soil and vegetable mat
ter within its reach. thus giving mor'
carbonic gas 10 the plants? This is tht
ouly rational explanation that can bt
given. and It is to the point.
Nov let us apply these principles
founded upon facts. The carbonic ga
being carried up in the sap, which is tn,
is water containing matters tor growth I'M