Burlington free press. [volume] (Burlington, Vt.) 1827-1865, 1836-12-23


carbon being in fact, identical with vegeta
bic mould.
We may hence infer that the following
elements exist in vegetable bodies:
|. Oxygen, developed in carbonic acid
water.
Q. Hydrogen is in the water and carbu-
rcts or hydrogen.
3. Carbon.
a. Earths.
5. Akalls.
6. Nitrogen, occasionally developed in
the form o! ammonia.
7. Acids, remaining in the insouble, or
washed away in the soluble salts.
The chemica examination of vegetable
bodies ought Of course lead to similar re-
suits. This examination has been conduc
ted in three different ways.
I. With the view of discovering the ma.
ture of the compounds called vegetable
principles, which exist, ready formed in
plants
2. For the purpose Of discovering the
chemical elements contained in these prin.
cipIes.
2. By the destructive action of heat, un.
der which some of the elements are wholly
separated, and others enter into new COM
bnalions.
In the LIST ofthese methods there have
been detected
/. Certain peculiar acids of which we
may cite,
~ Acetic acid, which, mixed with wa
ter, forms common vinegar;
(2) Citric acid. which is found in the
lemon and orange.
~ Malic acid which exists in the apple.
(4) Tartaric acid in the juice of the
grape.
t5) Oxalic acid in the wild sorrel.
H. Certain substances of alkaline char
acter, found principally in the medicinal
plants, TO which they give their peculiar
virtues.
Gum, rosin, oils. sugar, starch, and two
substances approaching to animal matter
IN their characters, namely, albumen and
gluten; the former of these has resem
bance to the white of eggs, the latter to
animal jelly or glue.
Many other principles are separated by
the same method in different plants, but
need not be enumerated by US.
\ The basis Of this method consists in act
ing upon vegetables by water, ether, or
rectlfed spirits (alcohoi) and the principles
above enumerated nre either simply, or in
the state of combination IN which they ex-
is' in plants, soluble in at least one of the
liquids we have named.
In all cases some insoluble matter is left
and this is known by the name of the woody
fibre.
When these principles are treated in the
sesond method, oxygen, hydrogen, and
carbon. are the uniform results, but in DIFF.
ferent proportions in the different cases
! nitrogen is also detected in some of them
J as, for instance in the alkaline principles
in gluten. This method does not appear
to be adequate to determine whether earth
or alkalls are or are no, parts of these We
getable principles. From the very remark
able fact, that some of those substances
which are very dissimar to each other
5 yield exactly the same proportions of oxy-
gen, hydrogen, and carbon, we may fairly
, conclude by chemica analogy, that one OF
! the other or perhaps both, contain some
substances which have escaped the analv.
5 sis. AS an instance we may cite starch
and sugar, whose characters are so dssim
, liar that no danger can exist of installing
! the one for the other and yet their analy
r sis by the second method gives identica
! results.
The third method may be understood by
: comparing it with the process used in ira
; king charcoal. If this be so far altered
that the heat employed shall no, arise from
: the combustion of a part of the substance
to be examined, but from one merely used
, as fuel. and if the matters which escape
in smoke are condensed and collected, We
: shall have that employed occasionally on q
large scale by operative chemists. In this
way charcoal will be as usual obtained in
, the solid form. The condensible products
, will be water, tar, turpentlne, or rosln; and
; the acid which gives the character to vim
{ egur. but which in the present case, in I'M
T ion with the tar and water, is called pyrol-
; igonous acid.
lfrhe charcoal be burnt in a current Of
! air, all its carbon is converted, by union
with the oxygen Of the atmosphere, into
5 carbonac acid, leaving residue famiary
r known as ashes. The ashes are made uT
partly Of soluble and partly of insolublf
r matter. The soluble matter is separated
by the familiar process of making ley, ant
, the ley, # eyaporaIed leaves the substance
! SO well known as potash
Potash is principally composed of ca DO
nate OF poiassa, but contains, besides silIcj
rendered soluble by the alkali, sui phatt
and muriatc of polassa, and peculiar acl,
known by the name of ulmlc, which is
compound of CARBON, hydrogen, and oxy
gen. The nsouble part is made up of car
Donate of lime, sulphate and sometime
phosphate of lime. silica. The carbonat,
of lime has probably in no case existed il
the living plant, but arises from III,
: destruction by heat of the peculiar aci'
e of the plant; as, for instance, the citrlc
: the oxalc, or the tauaric all of which
are by fire converted into calbonic acid.
The quantity of ashes is extremely vari
I Gus, as Is their proportion of the severa
soluble and insouble substances, we have
/, mentioned, Thus the ashes of the stalk
& Of Indian corn yiolds 10 10 nor cnpt n