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the stalks contain, even under the present
injudicious mode of treating it, is very
great, and if cut and steamed as it should



be, would add most materially to the
means of feeding; and every one who h^S' i'
travelled at the south knows the avidity
with which the northern as well as the
southern horse feeds on corn leaf fodder.
We would add here, that in our opinion
much of the relief, not to say cure, expe-
rienced by horses from the north subject to
the heaves, when taken to the south, arise
from substituting the clean grateful corn
leaf as food, in the room of tiie too fre-
quently mouldy, and always dusty hay of
the north.

In a season of drought like the past,
an acre or two of corn like Mr. Holt's
sown broad cast, and of good growth,
would have been a most material aid in
supplying the many half starved cattle and
horses that were to be seen even in our
fertile western New York with the most
nourishing food; and if not wanted for that
purpose in the summer, by being cut and
dried, would make a supply of winter
food far greater and more valuable than
could be obtained in a dry state in any i
other way.

The system of soiling it is evident re-
quire rich lands to grow the food; and it
is clear there is no method so well calcula-
ted as this to keep lands rich. We think
it might be made a most profitable part of
our mode of farming; on our rich grain
growing farms, by enabling us to keep
greater quantities of stock than we are
now able to do; thus securing at once
greater sources of comfort and profit, and
the most effectual means of retaining the
fertility of our soils.



CHILBLAINS.

Many persons, especially children, suf-
fer from chilblains, although this trouble-
some affection is often met vviih in the
most healthy constitutions; yet when the
disease proceeds to a very great extent
and degree of intensity, and occurs with
violence, where the exciting cause, expo-
sure to changes of temperature has not
been sudden or remarkable, we may then
conclude that the sufferer's diathesis is de-
cidedly scrofulous. This affection ought
consequently to excite the attention of j)a-
rents; for although in general it is merely
a local ailment, yet in some children it in-
dicates a general weakness of the consti-
tion, and in all, occasions much pain and



CHILBLAINS.



93



a'nnoyance. Sir Benjamin Brodie, by Fiis
adnnirable observations on the nature and
ire of corns, published in the 17th vol-

16 of the Medical Gazette, has shown
hat affections, vulo^arly reputed to be be-
leath the dignity of the medical profess-
ion, may afford a legitimate and ample
field for our interference and assistance.
In order to prevent the formation of chil-
blains, we must endeavour to protect the
skin from the operation of the usual exci-
ting cause of the disease, and, in addition
to cautioning the children to avoid expos-
ing their hands or feet to rapid transitions
from cold to heat, we should endeavour to
render the skin capable of bearing mode-
Tatc changes of temperature with impuni-
ty. This is best effected by washing the
hands several times a day, at first with te-
pid and afterwards with cold water, mix-
ed with a small portion of spirits or of eau
de Cologne.

Some parents do much injury by mak-
ing their children wear flannel or Avoolen
gloves, even in the house. Stimulating
liquids, such as strong brine, have long
been deservedly popular as preventives of
chilblains, and were recommended by Di-
oscorides; but none of those usually cm-
ployed seem to me as efficacious as one
which I was the first to use; viz. a solution
of sulphate of copper in water, in the pro-
portion of ten grains to the ounce. This
must be diligently applied to aff^ected or
suspected parts of the skin with a camel's
hair pencil; and as soon as the moisture
dries off", the skin should be well smeared
over with spermaceti ointment.

.The sulphate of copper lotion may be

applied two or three evenings in success-
ion, until it has produced a manifest effect
on the skin; it must be then discontinued
for a few nights, again however to be re-
sumed as soon as the natural soft and ten-
der texture of the skin seems about to re-
turn. You must be careful to enjoin the
application of the spermaceti after each
use of the lotion. By this simple plan,
commenced early in winter, many chil-
dren, previously martyrs to chilblains,
have been completely protected. It is pro-
bable that the nitrate of silver would an-
swer equally well, did it not discolour the
skin in so unseemly a way. — Dr. Graves
on Chilblains.



HUNTER ON CHILBLAINS.

Chilblains are the common effects of
these causes, viz. the want of power in the
system to generate heat. Cold is a pow-
erful obstructor of the natural animal
powers, whilst at the same lime it is ex-
citing action, producing irritable inflam-
mation and death. It is a true cause of
mortification.

Indolent swellings from cold arise from
two diflferent modes of action:

1st. When so gradually npplied as not
to excite irritable inflammation, but a gra-
dual, sluggishness.

2nd. When it produces irritable inflam-
mation from the parts being weakened.
Cold does not immediately obstruct the
natural actions of the whole, or part, but
excites the whole or part to another ac-
tion, viz. the production of heat. The ex-
tremities, from their great distance from
the seat of the living power, and from be-
ing smaller, are most liable to this. Thus
these parts become first irritable, and
then inflamed; but it is an increased dis-
position to act, with lessened powers.
Hence the eflfects of cold are greater or
less, according to the constitution. The
weakly, the fair, and the delicate, have
the least power of generating heat. From
the foregoing effects of cold we are led to
a rational cure, first to remove the cause,
then to apply warmth, or rather to keep
the parts temperate.

Chilblains commonly get well in sum-
mer. The cure, perhaps, should be divi-
ded according to the two stages of the dis-
ease, viz. the irritable and indolent; but
how far the treatment should correspond
in this way, I cannot say. They have been
cured when they looked purple and livid,
by gentle stimulants, as oleum terebinthi-
nas, or camphorated spirits of wine. Such
applications bring on the florid red of in-
flammation, which generally terminates
well, for Ihey seem to counteract the sti-
mulus or irritation of cold.

Steeping the parts in warm vinegar has
done much good; when they ulcerate, the
same exciting mode seems best. But they
are sometimes so irritable as to require
quieting; for which purpose a poultice or
decoction of poppy heads is equal to any
thing.

When the itching begins, rubbing the



94



AGRICULTURAL CHEMISTRY.



feet over with pounded chalk will be ef-|gen, and its constitution is consequently
factual to prevent it; the rubbing; is useful, 75 potassium, 15 oxygen



and the chalk keeps the feet warm by be-
ing a bad conductor of heat.

The invisible causes of indolent dispo-
sitions are also various. The first of the
spontaneous is a diseased increase of
growth.

2nd. Interstitial swelling.

.3d. New formed substance.

This division, according to the mode of
increase, is into three kinds, viz. increase
of natural parts, the interstitial, and the
tumour. All these are liable to happen in
every part of the body. These increases
are either known by the sight or by the
feel.

AGRICULTURAL CHEMISTRY.

(Continued from p. 78.)

Combustion in fact, in common cases,
is the ])rocess of the solution of a body in
oxygen, as happens when sulphur or char-
coal is burnt; or the fixation of oxygen by
the combustible body in a solid form,
which takes place when most metals are
burnt, or when phosphorus inflames, or
the production of a fluid from both bodies,
as when hydrogen and oxygen unite to
form water.

When considerable quantities of oxy-
gen or of chlorine unite to metals, or in-
flammable bodies, they often produce
acids; thus sulphurous, phosphoric, and
boracic acids, are formed by a union of
considerable quantities of oxygen with
sulphur, phosphorus, and boron: and mu-
riatic acid gas is formed by the union of
chlorine and hydrogen.

When smaller quantities of oxygen or
chlorine unite with inflammable bodies or
metals, they form substances not acid, and
more or less soluble in water; and the me-
tallic oxides, the fixed alkalies, and the
earths, all bodies connected by analogies,
are produced by the union of metals with
oxygen.

The composition of any compounds,
the nature of which is well known, may
be easily learned from the numbers repre-
senting their elements; all that is necessa-
ry is to know how many proportions enter
into union. Thus potassa, or the pure
caustic vegetable alkali, consists of one
proportion of potassium and one of oxy-



Carbonic acid is composed of two pro-
portions of oxygen, 30, and one of carbon,
11,4.

Again, lime consists of one proportion
of calcium and one of oxygen, and it is
composed of 40 of calcium and 15 of oxy-
gen.

And Carbonate of lime, or pure chalk,
consists of one proportion of carbonic acid,
41.4, and one of lime, 55.

Water consists of two proportions of
hydrogen, 2, and one of oxygen, 15; and
when water unites to other bodies in defi-
nite proportions, the quantity is 17, or
some multiple of 17, i. e. 34, or 51, or
68, &c.

Soda, or the mineral alkali, contains
two proportions of oxygen to one of so-
dium.

Jiinrnonia, or the volatile alkali, is
composed of six proportions of hydrogen
and one of azote.

Amongst the earths, Silica, or the earth
of flints, probably consists of two propor-
tions of oxygen to one of silicum; and
Magnesia, Slrontia, Baryta or Bary-
tes, Mxnnina, Zircona, Glusina, and
Ittria, of one proportion of metal and one
of oxygen.

The metallic oxides in general consist
of the metals united to from one to four
proportions of oxygen; and there are, in
some cases, many different oxides of the
same metal; thus there are three oxides of
lead; the yellow oxide or massicot, con-
tains two proportions of oxygen; the red
oxide or minium, three; and thejot^ee co^
loured oxide, four proportions.

Again, there are two oxides of copper ^
the black and the orange; the black con-
tains two proportions of oxygen, the
orange one.

For pursuing such experiments on the
composition of bodies as are connected
with agricultural chemistry, a few only of
the undecompounded substances are ne-
cessary; and amongst the compounded bo-
dies, the common acids, the alkalies, the
earths, are the most essential substances.
The elements found in vegetables, as has
been stated in the introductory lecture,
are very few. Oxygen, hydrogen, and
carbon, constitute the greatest part of their



AGKICULTUKAL CHEMISTRY.



95



organized matter. Azote, phosphorus,
sulphur, manganesum, iron, silicum, cal-
cium, aluminum, and mngnesium, like-
wise, in different arrangements, enter into
their composition, or are found in the
agents to which they are exposed; and
these twelve undecompodnded substances
are the elements, the study of which is of
the most importance to the agricultural
chemist.

The doctrine of definite combinations,
as will be shown in the following lectures,
will assist us in gaining just views respect-
ing the composition of plants and the eco-
nomy of the vegetable kingdom; but the
same accuracy of weight and measure, the
same statical results which depends upon
the uniformity of the laws that govern
dead matter, cannot be expected in opera-
tions where the powers of life are concern-
ed, and where a diversity of organs and of
functions exist.

The classes of definite inorganic bodies,
even if we include all the crystalline ar-
rangements of the mineral kingdom, are
few, compared with the forms and sub-
stances belonging to animated nature.
Life gives a peculiar character to all its
productions; the power of attraction and
repulsion, combination and decomposition,
are subservient to it; a few elements, by
the diversity of their arrangement, are
made to form the most different substan-
ces, and similar substances are produced
from compounds which, when superficial-
ly examined, appear entirely diiferent.

LECTURE IIL

On the Organization of Plants. Of the
roots, trunk, and branches. Of their
structure. Of the Epidermis. Of the
cortical and alburnous parts of leaves,
Jiowers, and seeds. Of the chemical
constitution of the organs of plants,
and the substances found in them. Of
mucilaginous, saccharine, extractive,
resinous and oily substances, and
other vegetable compounds, their ar-
rangements in the organs of plaiits,
their composition, changes and uses.

Variety characterizes the vegetable
kingdom, yet there is an analogy between
the forms and the functions of all the dif-
ferent classes of plants, and on this analo-



gy the scientific principles relating to their
organization depend.

Vegetal)les are living structures distin-
guished from animals by exhibiting no
signs of perception or of voluntary mo-
tion; and their organs are either organs of
nourishment or of reproduction, organs
for the preservation and increase of the in-
dividual, or for the multiplication of the
species.

In the living vegetable system there are
to be considered, the exterior form, and
the interior constitution.

Every plant examined as to external
structure displays at least four systems of
organs, or some analogous parts.
Fiist, the Root.

Secondly, the Trunk and Branches,
or Stem.

Thirdly, the Leaves.
And fourthly, the Flowers or Seeds.
The root is that part of the vegetable
which least impresses the eye; but it is
absolutely necessary. It attaches the plant
to the surface, is its organ of nourishment,
and the apparatus by which it imbibes food
from the soil.

The roots of plants, in their anatomical
division, are very similar to the trunk and
branches. The root may indeed be said
to be a continuation of the trunk, termina-
ting in minute ramifications and filaments,
and not in leaves; and by burying the
branches of certain trees in the soil, and
elevating the roots in the atmosphere,
there is, as it were, an inversion of the
functions — the roots produce buds and
leaves, and the branches shoot out into
radical fibres and tubes. This experiment
was made by Woodward on the willow,
and has been repeated by a number of
physiologists.

When the branch or root of a tree is cut
transversely, it usually exhibits three bo-
dies — the bark, the wood, and the pith;
and these again are individually suscepti-
ble of a new division.

The bark when perfectly formed is co-
vered by a thin cuticle or epidermis,
which may be easily separated. It is ge-
nerally composed of a number of laminae
or scales, which in old trees are usually in
a loose and decaying slate. The epider-
mis is not vascular, and it merely defends
the interior parts from injury. In forest



96



CONTENTS.



trees, and in the larger shrubs, the bodies
of which are firm, and of strong, texture,
it is a ])art of little importance; but in the
reeds, the grasses, canes, and the plants
having hollow stalks, it is of great use,
and is exceedingly strong, and in the mi-
croscope seems composed of a kind of
glassy net-work, which is principally sili-
ceous earth.

This is the case in wheat, in the oat,
in the different species of equisetum, and,
above all, in the rattan, the epidermis of
which contains a sufficient quantity of
flint to give light when struck by steel,
or two pieces rubbed together produce
sparks. This fact first occurred to me in
1798, and it led to experiments, by which
I ascertained that siliceous earth existed
generally in the epidermis of the hollow
plants. The siliceous epidermis serves as
a support, protects the bark from the ac-
tion of insects, and seems to perform a
part in the economy of these feeble vege-
table tribes, similar to that performed in
the animal kingdom by the shell of the
crustaceous insects.

Immediately beneath the epidermis is
\\\Q parenchyma. It is a soft substance,
consisting of cells filled with fluid, having
almost always a greenish tint. The cells
in the parenchymatous part, when exam-
ined by the microscope, appear hexagon-
al. This form, indeed, is that usually af-
fected by the cellular membranes in vege-
tables, and it seems to be the result of the



general reaction of the solid ))arts, similar
to that which takes place in the honey-
comb.

This arrangement, which has been
usually ascribed to the skill and artifice of
the bee, seems, as Dr, Woolaston has ob-
served, to be merely the result of the me-
chanical laws which influence the pressure
of cylinders composed of soft materials,



Online LibraryD. PeirceObserver and record of agriculture, Science and art (Volume v.1) → online text (page 18 of 35)