Lynchburg Virginian. [volume] (Lynchburg [Va.]) 1829-185?, 1829-07-02

From The Neio Engla,id Farmer.
CIRCULATION OF SAP IN TREES, &C.
We are told that all plants are composed Of
| solid and fluid parts the sold parts remain
stationary the fluids change" Varying" say
the writers, q" continually both in me chanica
admixture and 10 chemical composiiion." The
primitive solid components Of the vegetabl,
textures, are membrane and Gbre-from which
are formed the common organic structures
the cellular and vascular tissues, and the VAR;
rons combinations Of these IN the bark" :" The
fluid elements are waiery solutions of the soln
BILE materials OF the sol from the decomposr
ion Of which, and the reconciliation Of their
ultimate componenis, by means OF mechanica'
and chemical agency, influenced by the princi.
pies of life, solid components, textures and Sc.
cretions are formed" The size of these cells
varies in different plants. and in d fferent parts
OF the same plant SO much so that some hre
visible 10 the naked eve, while others are So
minute thst is said they require a million to
cover a square inch Of surface. They are also
II different forms, but generally octagon.
Some phisoo2 lists cont nd that these are chan.
nels through which the sap rises; Others di,-
,,ne it.-But all agree, believe, that they con.
ain proper Juices, aud iha some receive and
transmit fluids oblquey. "The cellular tis-
a
oIogy," besides continuing water, fluid and air
.ontain sugary, re,lnous, oily acid, and saline
.ecre,ions" al is also the medium BY which
The descending proper juice, or elaborated sap
is d, fused Sideways through the plant; and ma
nv changes, effected by elecrochemical agen-
cy. occur IN the juices " hch fill It's cells II
this opinion be correct, the third question oil
Mr. Coffin seems TO he answered.
From experiments bat have been mnde. il
appears that if wig be cut, with the leaves
expanded, by putting the cut end into walery
solution of Brazil wuod The coloring matter
will asce nd into the leaves, and 10 the top OF
the shoot, through real organic tubes /; these
are the sap. or conducting vessels Of The plant
This is said TO be owing TO The perspiratIon, OF
Transportation which is 81 i'll going on while the
leaves are fresh OH a newly cut shoot. Bull II
the lwig be deprived Of its leaves, the waie,
will not a scend far. A:a later period Of tue
SEASON if we make a transverse cut oil branch
the wood appears dry, while the bark rear the
wood is filed with fluid. This is contained IN
vessels of different description from those
in which the sap rises The first being placed
in the ba.k only in trees, and are called proper
vessels, or returning vessels, from their func
ton Of carrying downwards the sap after its e
iaboraton in the leaf Is il, then, that the per
spiraiiop Of plants is one Of the means by which
the sap is brought into circulation
That there is considerable connection be
tween the perspiraiion of plants, and the cit
culation OF the sap there can be but little doubt
from the various experiments that have beer
mad. DR.. Hales tells us, that he took seyera
branches of pear tree, on some of which he
left the leaves, while be stripped them from the
others. All these branches were then accu
raiely weighed, aud the cut ends put into yes
sells which contained a certain weight or guam