Gentle Measures in the Management and Training of the Young by Jacob Abbott (e book reader online .txt) 📖

new combinations, in which they are united by very weak affinities. Of course, they have a strong tendency to break away from the new unions, and fall back into the old. But, by some mysterious and incomprehensible means, the sun has power to lock them, so to speak, in their new forms, so as to require a special condition of things for the releasing of them. Thus they form a reserve of force, which can be held in restraint until the conditions required for their release are realized.

The process can be illustrated more particularly by a single case. Water, one of the substances absorbed by plants, is composed of oxygen and hydrogen, which are united by an affinity of prodigious force. It is the same with carbon and oxygen, in a compound called carbonic acid, which is also one of the principal substances absorbed by plants from the air. Now the heat and other emanations from the sun, acting upon these substances in the leaves, forces the hydrogen and the carbon away from their strong bond of union with oxygen, and sets the oxygen free, and then combines the carbon and hydrogen into a sort of unwilling union with each other—a union from which they are always ready and eager to break away, that they may return to their union with the object of their former and much stronger attachment—namely, oxygen; though they are so locked, by some mysterious means, that they can not break away except when certain conditions necessary to their release are realized.

Hydrocarbons.

The substances thus formed by a weak union of carbon with hydrogen are called hydrocarbons. They comprise nearly all the highly inflammable vegetable substances. Their being combustible means simply that they have a great disposition to resume their union with oxygen—combustion being nothing other than a more or less violent return of a substance to a union with oxygen or some other such substance, usually one from which it had formerly been separated by force—giving out again by its return, in the form of heat, the force by which the original separation had been effected.

A compound formed thus of substances united by very weak affinities, so that they are always ready to separate from each other and form new unions under the influence of stronger affinities, is said to be in a state of unstable equilibrium. It is the function of vegetable life to create these unstable combinations by means of the force derived from the sun; and the combinations, when formed, of course hold the force which formed them in reserve, ready to make itself manifest whenever it is released. Animals receive these substances into their systems in their food. A portion of them they retain, re-arranging the components in some cases so as to form new compounds, but still unstable. These they use in constructing the tissues of the animal system, and some they reserve for future use. As fast as they require the heat and the force which are stored in them they expend, them, thus recovering the force which was absorbed in the formation of them, and which now, on being released, re-appears in the three forms of animal heat, muscular motion, and cerebral or nervous energy.

There are other modes besides the processes of animal life by which the reserved force laid up by the vegetable process in these unstable compounds may be released. In many cases it releases itself under ordinary exposures to the oxygen of the atmosphere. A log of wood—which is composed chiefly of carbon and hydrogen in an unstable union—lying upon the ground will gradually decay, as we term it—that is, its elements will separate from each other, and form new unions with the elements of the surrounding air, thus returning to their normal condition. They give out, in so doing, a low degree of heat, which, being protracted through a course of years, makes up, in the end, the precise equivalent of that expended by the sun in forming the wood—that is, the power expended in the formation of the wood is all released in the dissolution of it.

This process may be greatly accelerated by heat. If a portion of the wood is raised in temperature to a certain point, the elements begin to combine with the oxygen near, with so much violence as to release the reserved power with great rapidity. And as this force re-appears in the form of heat, the next portions of the wood are at once raised to the right temperature to allow the process of reoxidation to go on rapidly with them. This is the process of combustion. Observations and experiments on decaying wood have been made, showing that the amount of heat developed by the combustion of a mass of wood, though much more intense for a time, is the same in amount as that which is set free by the slower process of re-oxidation by gradual decay; both being the equivalent of the amount absorbed by the leaves from the sun, in the process of deoxidizing the carbon and hydrogen when the wood was formed.

The force imprisoned in these unstable compounds may be held in reserve for an unlimited period, so long as all opportunity is denied them of returning the elements that compose them to their original combinations. Such a case occurs when large beds of vegetable substances are buried under layers of sediment which subsequently become stone, and thus shut the hydrocarbonaceous compounds beneath them from all access to oxygen. The beds of coal thus formed retain their reserved force for periods of immense duration; and when at length the material thus protected is brought to the surface, and made to give up its treasured power, it manifests its efficiency in driving machinery, propelling trains, heating furnaces, or diffusing warmth and comfort around the family fireside. In all these cases the heat and power developed from the coal is heat and power derived originally from the sun, and now set free, after having lain dormant thousands and perhaps millions of years.

This simple case of the formation of hydrocarbons from the elements furnished by carbonic acid and water is only adduced as an illustration of the general principle. The modes by which the power of the sun actually takes effect in the decomposition of stable compounds, and the formation of unstable ones from the elements thus obtained, are innumerable, and the processes as well as the combinations that result are extremely complicated. These processes include not only the first formation of the unstable compounds in the leaf, but also an endless series of modifications and re-arrangements which they subsequently undergo, as well in the other organs of the plant as in those of the animal when they are finally introduced into an animal system. In all, however, the general result is substantially the same—namely, the forcing of elements into unnatural combinations, so to speak, by the power of the sun acting through the instrumentality of vegetation, in order that they may subsequently, in the animal system, give out that power again by the effort they make to release themselves from the coercion imposed upon them, and to return to the natural unions in which they can find again stability and repose.

One of the chief elements employed in the formation of these weakly-combined substances is nitrogen—its compounds being designated as nitrogenous substances, and noted, as a class, for the facility with which they are decomposed. Nitrogen is, in fact, the great weak-holder of nature. Young students in chemistry, when they learn that nitrogen is distinguished by the weakness of its affinities for other elements, and its consequent great inertness as a chemical agent, are often astonished to find that its compounds—such as nitric acid, nitre, which gives its explosive character to gunpowder, nitro-glycerine, gun-cotton, and various other explosive substances which it helps to form—are among the most remarkable in nature for the violence and intensity of their action, and for the extent to which the principle of vitality avails itself of them as magazines of force, upon which to draw in the fulfillment of its various functions.

186 GENTLE MEASURES.

But this is really just what should be expected. It is the very weakness of the hold which nitrogen maintains upon the elements combined with it that facilitates their release, and affords them the opportunity to seize with so much avidity and violence on those for which they have a strong attraction.

It is as if a huntsman should conduct a pack of ferocious dogs into a field occupied by a flock of sheep, quietly grazing, holding the dogs securely by very strong leashes. The quiet and repose of the field might not be seriously disturbed; but if, on the other hand, a child comes in, leading the dogs by threads which they can easily sunder, a scene of the greatest violence and confusion would ensue.

In the same manner, when nitrogen, holding the particles of oxygen with which it is combined in the compounds above named by a very feeble control, brings them into the presence of other substances for which they have a very strong affinity, they release themselves at once from their weak custodian, and rush into the combinations which their nature demands with so much avidity as to produce combustions, deflagrations, and explosions of the most violent character.

The force which the elements display in these reunions is always—and this is one aspect of the great discovery of modern times in respect to the persistence or constancy of force which has already been referred to—precisely the same in amount as that which was required for dissevering them from their original combinations with such substances at some previous time. The processes of vegetation are the chief means employed for effecting the original separations, by the power of the sun, and for forming the unstable compounds by which this power is held in reserve. The animal system, on the other hand, takes in these compounds, remodels them so far as is required to adapt them to its structure, assimilates them, and then, as occasion requires quires, it releases the concealed force, which then manifests itself in the forms of animal heat, of muscular motion, and of cerebral and nervous power.

In what way, and to what extent, the knowledge of these truths should influence us in the management and training of children in respect to their extraordinary activity, is the question we have next to consider.

Practical Applications of these Principles.

If we watch a bird for a little while hopping along upon the ground, and up and down between the ground and the branches of a tree, we shall at first be surprised at his incessant activity, and next, if we reflect a little, at the utter aimlessness and uselessness of it. He runs a little way along the path; then he hops up upon a twig, then down again upon the ground; then "makes believe" peck at something which he imagines or pretends that he sees in the grass; then, canting his head to one side and upward, the branch of a tree there happens to strike his eye, upon which he at once flies up to it. Perching himself upon it for the moment, he utters a burst of joyous song, and then, instantly afterwards, down he comes upon the ground again, runs along, stops, runs along a little farther, stops again, looks around him a moment, as if wondering what to do next, and then flies off out of our field of view. If we could follow, and had patience to watch him so long, we should find him continuing this incessantly changing but never-ceasing activity all the day long.

We sometimes imagine that the bird's movements are to be explained by supposing that he is engaged in the search for food in these evolutions. But when we reflect how small a quantity of food his little crop will contain, we shall be at once convinced that a large proportion of his apparent pecking for food is only make-believe, and that he moves thus incessantly not so much on account of the end he seeks to attain by it, as on account of the very pleasure of the motion. He hops about and pecks, not for the love of any thing he expects to find, but just for the love of hopping and pecking.

The real explanation is that the food which he has taken is delivering up, within his system, the force stored in it that was received originally from the beams of the sun, while the plant which produced it was growing. This force must have an outlet, and it finds this outlet in the incessant activity of the bird's muscles and brain. The various objects which attract his attention without, invite the force to expend itself in certain special directions; but the impelling cause is within, and not without; and were there nothing without