The Elements of Agriculture A Book for Young Farmers, with Questions Prepared for the Use of Schools, George E. Waring [read aloud books TXT] 📗

1 (THE PLANT) CHAPTER VII (LOCATION OF THE PROXIMATES AND VARIATIONS IN THE ASHES OF PLANTS) Pg 47

 

Another important fact concerning the ashes of plants is the difference of their composition in different plants. Thus, the most prominent ingredient in the ash of the potato is potash; of wheat and other grains, phosphoric acid; of meadow hay, silica; of clover, lime; of beans, potash, etc. In grain, potash (or soda), etc., are among the important ingredients.

[Of what advantage are these differences to the farmer?

Of what are plants composed?]

These differences are of great importance to the practical farmer, as by understanding what kind of plants use the most of one ingredient, and what kind requires another in large proportion, he can regulate his crops so as to prevent his soil from being exhausted more in one ingredient than in the others, and can also manure his land with reference to the crop which he intends to grow. The tables of analyses in the fifth section will point out these differences accurately.

FOOTNOTES Pg 48

 

[J] This pectic acid gelatinizes food in the stomach, and thus renders it more digestible.

[K] See Johnston's Elements, page 41.

[L] Sifted through a fine cloth called a bolting cloth.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 49

 

We have now learned as much about the plant as is required for our immediate uses, and we will carefully reconsider the various points with a view to fixing them permanently in the mind.

Plants are composed of organic and inorganic matter.

[What is organic matter? Inorganic?

Of what does organic matter consist? Inorganic?

How do plants obtain their organic food?

How their inorganic?

How is ammonia supplied? Carbonic acid?]

Organic matter is that which burns away in the fire. Inorganic matter is the ash left after burning.

The organic matter of plants consists of three gases, oxygen, hydrogen and nitrogen, and one solid substance carbon (or charcoal). The inorganic matter of plants consists of potash, soda, lime, magnesia, sulphuric acid, phosphoric acid, chlorine, silica, oxide of iron, and oxide of manganese.

Plants obtain their organic food as follows:--Oxygen and hydrogen from water, nitrogen from some compound containing nitrogen (chiefly from ammonia), and carbon from the atmosphere where it exists as carbonic acid--a gas.

They obtain their inorganic food from the soil.

The water which supplies oxygen and hydrogen to plants is readily obtained without the assistance of manures.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 50

 

Ammonia is obtained from the atmosphere, by being absorbed by rain and carried into the soil, and it enters plants through their roots. It may be artificially supplied in the form of animal manure with profit.

Carbonic acid is absorbed from the atmosphere by leaves, and decomposed in the green parts of plants under the influence of daylight; the carbon is retained, and the oxygen is returned to the atmosphere.

[When plants are destroyed by combustion or decay, what becomes of their constituents?

How does the inorganic matter enter the plant?

Are the alkalies soluble in their pure forms?

Which one of them is injurious when too largely present?

How may sulphuric acid be supplied?

Is phosphoric acid important?

How must silica be treated?

From what source may we obtain chlorine?]

When plants are destroyed by decay, or burning, their organic constituents pass away as water, ammonia, carbonic acid, etc., ready again to be taken up by other plants.

The inorganic matters in the soil can enter the plant only when dissolved in water. Potash, soda, lime, and magnesia, are soluble in their pure forms. Magnesia is injurious when present in too large quantities.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 51

 

Sulphuric acid is often necessary as a manure, and is usually most available in the form of sulphate of lime or plaster. It is also valuable in its pure form to prevent the escape of ammonia from composts.

Phosphoric acid is highly important, from its frequent deficiency in worn-out soils. It is available only under certain conditions which will be described in the section on manures.

Silica is the base of common sand, and must be united to an alkali before it can be used by the plant, because it is insoluble except when so united.

Chlorine is a constituent of common salt (chloride of sodium), and from this source may be obtained in sufficient quantities for manurial purposes.

[What is the difference between peroxide and protoxide of iron?

How must the food of plants be supplied?

What takes place after it enters the plant?

What name is given to the compounds thus formed?

How are proximates divided?

Which class constitutes the largest part of the plant?

Of what are animals composed, and how do they obtain the materials from which to form their growth?]

Oxide of iron is iron rust.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 52

 

There are two oxides of iron, the peroxide (red) and the protoxide (black). The former is a fertilizer, and the latter poisons plants.

Oxide of manganese is often absent from the ashes of our cultivated plants.

The food of plants, both organic and inorganic, must be supplied in certain proportions, and at the time when it is required. In the plant, this food undergoes such chemical changes as are necessary to growth.

The compounds formed by these chemical combinations are called proximates.

Proximates are of two classes, those not containing nitrogen, and those which do contain it.

The first class constitute nearly the whole plant.

The second class, although small in quantity, are of the greatest importance to the farmer, as from them all animal muscle is made.

Animals, like plants, are composed of both organic and inorganic matter, and their bodies are obtained directly or indirectly from plants.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 53

 

[What parts of the animal belong to the first class of proximates?

What to the second?

What is necessary to the perfect development of animals?

Why are seeds valuable for working animals?

What other important use, in animal economy, have proximates of the first class?

Under what circumstances is animal fat decomposed?]

The first class of proximates in animals comprise the fat, and like tissues.

The second class form the muscle, hair, gelatine of the bones, etc.

In order that they may be perfectly developed, animals must eat both classes of proximates, and in the proportions required by their natures.

They require the phosphate of lime and other inorganic food which exist in plants.

Seeds are the best adapted to the uses of working animals, because they are rich in all kinds of food required.

Aside from their use in the formation of fat, proximates of the first class are employed in the lungs, as fuel to keep up animal heat, which is produced (as in fire and decay) by the decomposition of these substances.

When the food is insufficient for the purposes of heat, the animal's own fat is decomposed, and carried to the lungs as fuel.

SECTION 1 (THE PLANT) CHAPTER VIII (RECAPITULATION) Pg 54