James F.W. (James Finley Weir) Johnston.

Catechism of agricultural chemistry and geology online

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En'ihind, and \aUior
I Geulogy, '



or Fartniti^on, Comieclicut.


Will. N.Mi-s and AddUioils by llie AuUior, prcpai'ed expressly for
this Edition.



1 8 ■; 'i .












From Hon. Saml. Young, Secretary of State and Super-
iniendent of Common Schools of the State of New-
York ;

I have carefully examined the Catechism of Professor
Johnston, on Agriculture. It is the only scientific work on
that subject I have ever seen, which by its shortness and
simplicity is adapted to the capacity of children ; and
which, on being illustrated by cheap and simple experi-
ments, as he recommends, cannot fail to make a lasting
impression on the juvenile mind.

It gives the analysis of different plants, of animals and
of soils, exhibiting the organic and inorganic substances of
which they are composed, and teaching the important
truths that vegetables drrive a part of their nourishment
from the air and the remainder from the earth ; that diffe-
rent vegetables require diflerent kimis of food and in va-
riable quantities ; that the soil may be destitute of nutri-
tion for one kind of plant and not for another ; ami the
means are explained of supplying to an exhausted or
meagre soil its deficiencies. It also gives the rationale of
the dairy and the fattening of animals.

This little work is the basis of both agricultural art and
science. A knowledge of its principles is within the com-
prehension of every child of twelve years old ; and if its
truths were impressed on the minds of the young, a foun-
dation would be laid for a vast improvement in that most
important occupation which feeds and clothes the human
race. Instead of conjecture, and hazard, and doubt and
experiment, as heretofore, a knowledge of the composition
of soils, the food of plants and the processes of nature in the
culture and growth of crops, would elevate agriculture to a
conspicuous rank among the exact sciences.

I hope that parents will be willing to introduce this brief
catechism into the Common Schools of this State.

Albany, 24th January, 1845.

Yale College, Laboratory, )
^ew■Haven, Ct., 20th Jany. ISib. S

I have read with great pleasure and profit the condensed
little Agricultural Catechism of Prof. James F. W. John-
ston of Scotland. Like every production of his pen, it is
characterized by a sound, practical good sense, vphich adds
double value to his scientific labors, rendering them availa-
ble to the very class for whom they are more es; ccially de-
signed — practical farmers.

I learned with pleasure from Prof. Johnston, that Mr.
John P. Norton was about to edit, with an introduction, his
Agricultural Catechism. This American edition should be
in every village school in the land , as being within the com-
prehension of all intelligent children : and it cannot indeed
be too highly recommended to the attention of all classes of
teachers, as the best synopsis yet made of the valuable facts
and principles which have been established in the important
science of agriculture.


I consider "J. F. W. Johnston's Catechism of Agricul-
tural Chemistry and Geology," to be extremely well adapt-
ed to the use of schools., and that it ought to be introduced
as a text-book into all our rural districts where farming is
the principal employment of the population. The time has
come when Agriculture is to be taught as a science as well
as cultivated as an art, and a little book like this sheds
more light on the nature of soils, the elementary principles
of plants, and the food necessary for their growth and ma-
turity, in a smallcompass, tlianany other publicalion I have
ever seen. The youthful mind can easily be made to com-
prehend the principles it teaches, and we are wanting to our
own and the great interests of our country, if at this time
we do not do all in our power to create a taste and diffuse a
knowledge of so important a pursuit.

late Prest. o/N. Y. S. A. Society.

Kinderhook, Jan. 22, 1845,

Having examined Professor Johnston's Catechism on
Agricultural Chemistry and Geology,! most cordially unite
in the recommendation of the work. Its introduction into
our Common Schools, will form a new era in the education
of our children. The time has arrived in which every pro-
per effort should be made to give such an education to the
rising generation as will prepare them rightly to appreciate,
as well as successfully to follow, the pursuits of agriculture,
for which most of them are designed. It will give me great
pleasure to do all in my power to disseminate this little
work, which I doubt not will produce the most happy effects
throughout our country.

President N. ¥. State J^ricultural Society.

Rome, Jan. 23d, 1845.

The apparatus necessary to perform the experiments
mentioned in this Catechism, may be had complete of Mr.
George Dexter, Albany, for $3.50 ; or a receiver and retort
with stand for from $1.25 to $2.00.








Honorary Member of the Royal Agricultural Society of England, and AuUlor
of " Lectures on Agricultural Chemistry and Geology."



Of Farmington, Connecticut.


With Notes and Additions by the Author, prepared expressly (or
this Edition.




Edtered according to Act of Coni^resg, in the year 1845, by


ia the Clerk's Office of the Nor±em District of New-Tork.




In introducing this little work to the notice of the
American public, I am encouraged by the hope that
a conviction as to the importance of the new know-
ledge of which it treats, already fixed in many
minds, will soon become universal. Agriculture,
the art in which nine-tenths of the capital of civil-
ized nations is embarked, upon which all depend
for subsistence, is rising towards its proper rank as
a science. We look forward to the time when it
will be generally conducted upon fixed and scienti-
fic principles, dependent upon immutabb laws.
Obstacles may retard, but cannot permanentl)- ar-
rest its progress, and those who receive the light
that we now possess, and keep pace with our in-
creasing knowledge, will surelj' reap the benefit
which always results from the application of en-
lightened skill; while those who linger behind
must be content to grope on in blind uncertainty, as
our forefathers have done.

fca'i/j onoo


I am, however, aware that we can scarcely expect
the present generation of farmers, engrossed with
the cares and business of life, with their prejudices
and habits of thought strengthened by years, gene-
rally to enter this new field, and to commence with
energy the study of what seems to them a formida-
ble science. But may we not with confidence hope
that they will cheerfully place the means of instruc-
tion within the reach of their children?

Scientific terms, and strict modes of reasoning,
are already becoming common in the daily inter-
course of agriculturists. In the next generation
this will become almost universal, and the farmer
who now neglects the instruction of his children in
elementary scientific knowledge, may with reason
apprehend that more skillful and better taught cul-
tivators, will hereafter thrust them aside, and oc-
cupy the places which they might have filled.

That children may be early and thoroughly
taught this elementary science, I have seen most
satisfactorily proved. At the late show of the High-
land and Agricultural Society, at Glasgow, five
bo)-s were present from the Lame School in Ire-
land. They were from twelve to sixteen years of
age, and were sons of small tenant farmers. In the
course of a searching public examination, they
evinced a knowledge of elementary chemistry, as


applied to agriculture, that was truly surprising;
and not only were they conversant with this branch
of chemistry, but with practical farming also. The
expressions of delight and satisfaction at the close
of the examination, were unanimous. These boys
are taught, it must be noticed, without neglecting
their other studies, as only two or three hours a
week are devoted to this branch of instruction.
When their course of study is complete, they are
either competent to take charge of their own farms,
or to act as land stewards or agents for others.

This system of instruction is about to be more or
less perfectly carried out in three thousand of the
Irish schools, and in Scotland a great change is
rapidly taking place. The schoolmasters, at their
aunual convention a few weeks since, decided unan-
imously to introduce a system somewhat resembling
the Irish, into all the Scottish schools. The zeal,
both of the masters and the people of Scotland, is
enthusiastic. What I have witnessed of it in va-
rious parts of this country, has made me desirous
that the subject should be brought under the consi-
deration of my own countrymen.

It seems to me that our circumstances, at least
in the northeastern and northern states, are pecu-
liarly favorable. We have in almost every village
an academy, or a school higher than the common


district schools, taught generally by graduates of
our colleges. How easy for these teachers to de-
vote two hours of their pupils' time in each week,
to the study of such a work as this Catechism I A
few shillings will supply all the apparatus necessa-
ry for the simple experiments it describes, and these
experiments will indelibly impress upon the youth-
ful mind, the nature and properties of carbon, oxy-
gen, nitrogen, and those other bodies which form
our plants, our food, ourselves, and the earth upon
which we live.

The district schools, also, might be made the
means of conveying similar information. Where
the community is interested, the teachers, I am con-
fident, will be found ready cheerfully to do their
part. I have met the parish and other schoolmas-
ters in various parts of Scotland ; they vie with
each other in their desire to attain and impart this
new knowledge. My own fellow-citizens, I am
sure, will not be less eager in their country's ser-

An attempt to recommend this Catechism by any
praise of mine, might seem presumptuous. The
wide and extensive reputation of its author — com-
bining in an eminent degree, theoretical with prac-
tical knowledge, and penetration with prudent cau-
tion, together with the fact that this little work, and


his Elements of Agricnltural Chemistry and Geo-
logy, are the text-books in all the Irish as well as
the Scottish schools, will be a sufficient guarantee
of its merit. I can therefore only express my ear-
nest desire that it may be the herald of agricultu-
ral school instruction in the United States. I trust
that it may be attentively perused by my country-
men generally, old as well as young; for I am sa-
tisfied that many will feel disposed, after reading
it, to follow the example of an Irish gentleman,
who thanked the author for having given him a

The present edition is reprinted from the eighth
English edition, with manuscript alterations and
Additions by the author.


Farmington, Conn.

Edinburgh, Nov., 1S44.



Having written the present little work
with a view to the more speedy improvement of the agri-
culttire of our common country, I take the liberty of dedi-
cating it to you. No class of men possesses in so high a
degree the power of promoting an object so important to
aU. I am anxious, therefore, to secure not only your
willing support, but, if possible, your cordial co-operation

The land from which our crops are raised must be ren-
dered more productive, if food is to be grown at home for
our increasing population. But the produce can be largely
increased only by the application of increased knowledge
to the culture of the soil; — and it is the rising generation
now under your care, which must possess and apply this
knowledge. You can scarcely render a higher service to
your country, therefore, than by imparting, along with
your other instructions, the rudiments of that kind of know-
ledge on which its prosperity must so greatly depend.
Few of your pupils will then escape from your hands so
early as not to have already learned what may enable
them on some spot or other in after life, " to make two
blades of grass to grow where only one grew before."
I have the honor to be.

Your obedient servant,



1st February, 1844.


The Author believes that the country teacher who may
introduce this little Catechism into his school, will find no
difficulty in making his elder classes understand the differ-
ent subjects which are successively adverted to. It will
not be necessary to make them commit the very words of
each answer to memory. They should be taught rather
to make themselves masters of the matter of each, so as
to be able to express the sense of the answers in words of
their own.

On first going over the questions, the pupil's attention
may be confined to such only as the teacher may consider
most important or most applicable to the practice of the
neighborhood in which he lives. The other questions
will be taken up on a second perusal, and an occasional
general catechising upon the whole book will fi.\ the mat-
ters treated of more firmly in the minds of his scholars.

The teacher himself will find further information in the
Author's Elements and pnhlished Lectures on Agricultural
Chemistry and Geology; and a set of apparatus especially
prepared for this Catechism, may be obtained from Rich-
ard GriiBn & Co., of Glasgow, at a cost of thirty shillings.




Q. What is agriculture'!

A. Agriculture is the art of cultivating the soil.
Q. IF hat is the object of the farmer in cultivating the
soil ?

A. The object of the farmer in cultivating the soil is,
to raise the largest crops at the smallest cost, and with
the least injury to the land.

Q. What ought the farmer especially to know, in order
that he may attain this object ?

A. The farmer ought especially to know ihe nature of
the crops he raises, of the land on which they grow, and
of the manures which he applies to the land.


Q. Of what parts do all vegetable substances consist ?

A. All vegetable substances consist ol two parts, one
which burns away in the fire, called the organic part,
and one which does not burn away, called the inorganic

Here Ihe teacher will burn a bit of straw or wooil in the
candle, (fi^. 1,) anil show that one part burns away, and
that another very small part — the ash — doesnot burn away



Q. Which of these livo parts is
the greater in quantity ?
A. In all veg-etable substances,
the organic part is very much the
greater. It forms from 90 to 99
out of every 100 lbs. of their

Q. Of what elementary bodies
does the organic part of
plants consist ?
A. The organic part of plants
consists of four elementary bodies, known by the names
of carbon, hydregen, oxygen and nitrogen.
Q. What is carbon.

A. Carbon is a solid substance, usually of black
colour, which has no taste or smell, and burns more or less
readily in the fire. Wood-charcoal, lamp-black, coke,
black-lead, and the diamond, are varieties of carbon.

The teacher will here exhibit a piece of charcoal and
show how it burns in the fire, or in the flame of a can-
iDe. He may also draw their attention to Uie remarkable
difference in appearance between cliarcoal and the dia-
mond, though essentially the same.

Q. What is hydrogen ?

A. Hydrogen is a kind of air or gas which burns in
the air as coal gas does, but in which a candle will not
burn, nor an animal live, and which, after being mixed
with common air, explodes when it is brought near the
flame of a candle. It is also the lightest of all known



Here the teacher will take a beer or
champaign glass, (fig. 2,) will put
into it some pieces of zinc or iron
filings, and pour over them a small
quantity of oil of vitriol (sulphuric
acid) diluted with twice ils bulk
of water, and cover the glass for a
few minutes. On putting in a
lighted taper, an explosion will
take place. He will then repeat
the same experiment in a phial,
into the cork of which he has introduced a common gas
jef, (Bg. 3.) After a short time, when the hydrogen gas
produced has driven out all the common air fi-om the bot-
Fig. 3. tie, a light may be applied to the

jet, when the gas will take fire and
burn. The cork and jet may now
be taken out of the bottle, and a
lighted taper introduced into it,
when the taper will be extjngushed,
while the gas itself will take fire
and burn at the mouth of the bottle.
Lastly, if the teacher possesses a
small balloon, he may fill it with
the gas by attaching it to the mouth
' the bottle, and may thus show that
the gas is so light that it will carry heavy bodies up with
it through the air.
Q. tVhat is oxygen ?

A. Oxygen is also a kind of air in which a candle
bitrns with great brilliancy, in which animals also can
live, and which is lieavier than hydrogen or common air.
It forms one-fifth of (he bulk of the air we breathe.



The teacher will here exhibit a bottle
of oxygen gas, (fig. 4,) ami show
how rapidly and brillianlly a lighted
taper burns when introiluccd into it.
The least troublesome mode of prepar-
ing oxygen gas, is lo heat red oxide
of mercury in a small retort by
means of a spirit lamp, and lo col-
lect the metallic mercury as it dis-
tils over and trickles down the beak
of the retort This is not so very
a costly process as it appears to be,
since there is no loss of anything. A
pound of red oxide costs 6s. Sd., and
gives 14 oz. of metallic mercury,
worth 4s. 8d.
Oxygen gas may also be prepared by mixing sulphuric acid
(oil of vitriol,) with black oxide of manganese, in fine pow-
der in a retort, and applying the heat oT a lamp ; or by rub-
bing together in a mortar e |ual weights of oxide of copper
and chlorate of potash, putting the mixture into a small re-
tort, and applying the lamp as before. The last is the
quickest method of the three.
Fig 5

* The properties of oxygen may be

very well shown without the neces-
sity of collecting the gas. Thus,
the mixture of chlorate of potash
and oxide of copper above descri-
beil, may be put into an open tube,
(flg. 5.) and the flame of a lamp
applied for a few minutes; when a
bit of red hot charcoal, or a match
of which a spark is still red at the
extremity, will burn brilliantly if introduced at a.



*'g- ". Or the mixluie may be put into a com-

mon open flasU, (tig. 6,) anil heat ap-
plied, when a taper, or phosphorus, or
charcoal, or sulphur, may be inlrmluc-
etl at the emi of a wire, and will burn

Q. IVhat is nitrogen ?

A. Nitrogen is also a kind of air

differing from both the other two.

Like hydrogen, a taper will not burn

nor will an aninnal live in it, but ui>-

like hydrogen, it will itself not burn,

and therefore does not take fire when hronght near ihe

flame of a candle. It is alillle lighter Ihan atmospheric

air, of which it forms four-fifths of the bulk.

Fig. 7.

The teacher will here exhibit a

bottle of this gas, and show
that a lighted taper is extin-
guished when introducei-l into
The easiest mode of preparing
nitrogen, is by mixing togeth-
er a quantity of sal ammoniac
with half ils weight of salt-
petre, both in tine powder,
and heating them in a retort
ovf r a lamp. The gas which comes off is collected over
water, as shown on the following page, (fig. 8.)


Fig. 8.

Q. Do all vegetable substances contain these four ele-
mentary bodies ?
A. No, the greater number contain only three, viz:
carbon, hydrogen, and oxygen.

Q. Name some of the more common substances which
contain only these three ?
A. Starch, gum, sugar, the fibre of wood, oils, and
fats, contain only these three elements.
Q. Of what substances does the inorganic part of the
plant consist ?
A. The inorganic part of plants contains from eight
to ten ditferent substances, namely : potash, soda, lime,
magnesia, oxide of iron, oxide of manganese, silica,
chlorine, sulphuric acid, or oil of vitriol, and phospho-
ric acid.

Here the teacher may exhibit to his pupils, potash in the
form oCthe common pearl ash of the shops; soila, in that
of the common soda of the shops; lime and magnesia, in


the lotmsol quicklime and calcined magnesia; oxide of iron,
in the form of rust of iron; silica, in the form of a piece
of Jlint, rock crystal or quartz, (chucky stone;) abottle of
chlorine gas, one of sulphuric acid, (oil of vitriol,) and
one containing a little phosphoric acid, or burnt bones
in which phosphoric acid is present. By placing the86
substances before the eyes of (he pupils occasionally,
and allowing them to determine and taste them, they
will soon become familiar with their names, and with
their several qualities.

Q. What is potash ?

A. The common potash of the sliops is a white pow-
der, which has a peculiar taste called an alcaline taste,
and which becomes moist, and at last runs to a liquid
when exposed for a length of time to the air. It is ob-
tained by washing wood ashes (the ashes left by wood
when it is burned,) with water, and afterwards boiling
the liquid to dryness.

The teacher will here allow his pupils to taste the potash,
that they may become familiar with the meaning of the
word alcaline as applied to (aste. (See p. 20.)
Q. What is soda ?

A. The common soda of the shops is a glassy or crys-
tallized substance, which has also an alcaline taste, but
which, unlike potash, becomes dry and powdery by being
exposed to the air. It is manufactured from sea salt.
The teacher will show a crystal of the common soda of the
shops, and explain the meaning of the word crystallized-
Q. What is lime?
A . Lime or gMicfe-lime is a white earthy substance


wliich is obtained by burning common limestone in Ihe
lime-kiln. It has a slightly burning taste, and becomes
hot and slakes when water is poured upon it.

The teacher will exhibit a piece of quicldimc, will allow
his pupils to tasle it, and will pour water upon it, that it
may fall to powiler. They will thus become familistr
with the word slake.
Q. IVhat is magnesia ?

A. Magnesia is the white powder sold in the shops
under the name of calcined mai;nesia. It has scarcely
any taste, and is extracted from sea water and from some
kinds of limestone rock called Magnesian limestones.
Q. H'hal is iron 7

A. Iron is a hard bluish gray metal, which is manu-
factured in large quantities incur iron- works, and is used
for a great variety of useful purposes.

The teacher will here explain the word metat, by show-
ing that such common metals as iron, copper, leail, sil-
ver and goUl, have a lustre, weight, anil malleability not
possessed by wood, stones, and other substances to which
the name of metals is not applied.
Q. ffhnt is oxide of iron ?

A. When polished iron is exposed to the air it gradu-
ally becomes covered with rust. This rust consists of
tbe metal iron, and of the gas oxygen which the iron has
attracted from the air, and hence it is called an oxide
of iron.

The teacher will explain more fully, that, when metals
combine with oxygen, they form new substances, to
Which the name of oxides is given, and illustrate this by


a reference to the red oxide of mercury, which, by the
heat of the lamp he had resolved or decomposed into oxy
gen gas and metallic mercury. (Sec. fig. 8.)
Q. What is oxide of manganese ?

A. Oxide of manganese is a substance very much like
oxide of iron, which occurs in soils and plants, usually

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Online LibraryJames F.W. (James Finley Weir) JohnstonCatechism of agricultural chemistry and geology → online text (page 1 of 5)