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WE think that many of our young readers, particularly those who live in the country, will be glad to learn something about the trees which they see around them on all sides in their daily walks; and we purpose, therefore, giving a short account of a few interesting facts connected with trees in general. To say all that could be said on the subject would require a volume instead of a chapter.
If we cut open the ripe seed of a tree, for instance, an acorn, which, as everybody knows, is the seed of an oak, there is found a small body, which is the germ of the future tree. When the seed is cast into the ground the germ swells, bursts the skin of the seed, and begins to grow in two directions, one end of it shooting upwards above the ground, and the other part shooting downwards and penetrating into the soil. The part which appears above the ground forms the stem, and the part which penetrates beneath the soil forms the root. The stem throws out branches in all directions, and, in like manner, the root spreads itself underground, often extending to a considerable distance from the stem. The branches bear the leaves and flowers, and from the latter is produced the seed. We shall have a few words to say upon each of the different parts, and we will begin with the root.
1. The root. This is that part by which the tree is supported, fed, and kept alive. The water which exists in the soil, together with the different sub
stances dissolved in it, is sucked in by the roots, passes into the other parts of the tree, and affords nourishment to the whole plant. The parts of the root which are most active in sucking in the food are the young extremities. It is, in fact, a question whether any other parts have this power; and the reason why trees are so apt to die when transplanted, is, that sufficient care is not taken to preserve the extremities of the roots uninjured during the process of moving. It is a curious circumstance that the roots have no power of selecting the food best adapted for keeping the tree in health. They will absorb poisons as easily as other substances, provided only the poison be so dissolved as to pass freely into the delicate extremities of the root. Although trees will thus absorb whatever is presented to the roots, yet, in order to preserve them in health, it is necessary that different trees should have different sorts of nourishment. We accordingly find that one kind of tree will flourish most in sandy soils, others in clayey soils, others in chalk, and so forth; the ingredients * of each of these different soils forming, when dissolved in water, the particular food best adapted for each particular tree.
2. The stem. This, as we have stated, is that part of the tree which grows upwards, and from which the branches proceed. The stems of the trees which grow in our English woods increase in growth, year by year, by the formation of new wood on the outside. If the stem of a tree of some years' growth is sawn across, there are seen a number of circles, one within the other, each circle being the formation of
* Ingredients.] The parts of which a thing is made up.
a single year. By counting the number of these circles, therefore, the age of the tree may be ascer tained. We mention particularly the trees of our English woods, because there are other trees, for instance, palms, which are met with in tropical countries, in which the mode of growth of the stem is quite different from that of our oaks and elms. The manner in which the branches proceed from the stem, and afterwards spread out into smaller branches, is the cause of the great variety of appearances which are found in different trees. Thus, in the cedar, the branches spread nearly at right angles, whilst in the poplar they form a sharp angle with the stem. In the birch and willow the branches bend with their own weight, causing the elegant drooping appearance of those trees.
3. The leaves.-These may be called the breathing organs of trees, that is to say, it is by means of the leaves that trees inhale, or draw in, from the air around them, the vapour and gases which are necessary to their well-being. It is through the leaves, also, that the vapour and gas which is contained in the tree, and which is not required to aid its health or growth, finds a means of escape or is exhaled. This breathing takes place by means of little pores, or breathing-holes, which are placed on the upper or under surface of the leaves in extraordinary numbers. In the leaves of the white lily there are about sixty thousand in a square inch on the under surface, and about three thousand in the same space on the upper. The greater part of leaves is made up of a vast number of little transparent* cells or bladders, and
* Transparent.] Which may be seen through.
their green colour arises from the colour of a certain waxy substance which is found within these cells. The beautiful tints which are seen upon different leaves in autumn are owing to a change of colour in the contents of the cells, caused by the action of the air. 4. The flowers. We have left ourselves but little space to speak of the flower. The flowers of some of the trees which are met with in our woods and gardens, as the elm, the oak, the hornbeam, &c., attract but little notice; others, as the horse-chestnut, the hawthorn, and the laburnum, produce blossoms of very great beauty. The flower is the most essential part of a tree, being the part in which the seed is produced.
5. The seed. The seed, as we have mentioned, contains within itself the rudiments* of the future tree. In due time, when fully ripened, it falls to the ground, and remaining buried for a short time, reappears in the form of a young plant, which passes through its stages of growth in a manner precisely similar to the parent tree, and exhibits in itself the wonders and the beauties of which, in the present chapter, we have given a short account.
*Rudiments.] First beginnings.
LABOUR AND CAPITAL.
Master. As you are to work for your living, Harry, have you ever thought what employment you would
Harry. I once thought it would be pleasant to
work in the fields and observe all the beauty of Nature; but I see that there are many trades in which the labourers are much better off than farm labourers. I think I should like to be a carpenter.
Master. If workmen in other trades are so much better off, why is it that all men do not choose to be carpenters, bricklayers, or the like?
Harry. They have not learnt the trade; I have been taught carpentering, and I know it takes a long time and a great deal of trouble to learn.
Master. It requires practice to be expert in any employment; but it is easier to learn the work of a farm labourer than of a carpenter, and a boy can sooner in that way make himself useful and earn wages. God has wisely ordered that the kind of labour of which most is wanted is most easy to practise; and the labour on a farm is healthful and improving to those who, in the works of Nature, look up to Nature's God. If the farm labourer has less wages, he must remember that he has had less trouble to learn his trade, and has sooner begun to profit by it. What is it then that you must have before you can attempt to be a carpenter?
Master. Very well. Skill is the gift of God. He has given you opportunity to learn, and has enabled you to profit by the lessons you have received. Your knowledge of this trade is a talent, and you are right to improve it to your own benefit, to the good of your fellow-creatures, and to the honour of God. Is anything else wanted before you can set up as a carpenter ? Harry. I must find a place where I am likely to obtain employment.