THE MINSTRELSY OF THE WOODS. INTRODUCTION. "Their little lives are free from care, And hears them when they cry. For ever blithe and blest are they, BLACKWOOD. EVERY study, the pursuit of which leads the young student out into the fields and woods, to observe, in minute detail, the wonderful works of the Author of nature, and learn how "in wisdom he hath made them all,"-every such study is alike healthful to body and mind. The botanist, with his fragrant wild-flowers and wreathed garlands; the entomologist, with his insect train, and all their wonderful transforma B tions and beautiful forms; the mineralogist, with his no less astonishing and interesting detailsall have their respective claims on our notice. But who comes on the field with more attractive trophies than the ornithologist? Who is there, that has not watched the swift-flying birds with delight, and listened with charmed ear to their thousand, thousand songs? The unpaid choristers of the groves are they-the musicians of all times and places. Roaming in the woods or fields, playing in the garden, climbing the mountain, or lingering by the side of the river or the sea-shore at home, or abroad, have you not often marked with delight, the rapid flight of the various birds passing swiftly through the air? Have you ever considered how it is that they can fly, while you can only walk and run? Perhaps you will say, because they have wings, and we have not. But this is not the only reason. Though you have no wings, you have arms and hands to supply their place, but with these cannot fly. It would be of no use to you to possess the power, and therefore the great Author of nature has not given it you. Your business is on the earth; but the necessities of birds require that they should be able to move freely through the air. To enable them to do this, they are very differently formed from you man and other animals. If it were possible for you to run as swiftly as the birds can fly, in a few minutes you would become almost breathless, and quite exhausted with the exertion. In order that they may be able to sustain the great efforts they make in flight, and the wonderful speed with which they move, they are formed in such a manner as to have a store of breath provided for their great necessities. To secure this advantage, there are air-vessels, or little cavities for the reception of air, almost all over their bodies; even in their bones, where air often supplies the place of marrow, as you may observe in the bones of a chicken, which have a much smaller proportion of marrow in them than the bones of quadrupeds. This singular provision of nature, besides enabling them to breathe more freely, increases their bulk without adding to their weight, and by that means gives a larger space for the muscles to act on, and so promotes the facility of their flight in another way This extension of the air-vessels, also effects more speedily the changes in the blood, and thus fits it for a more rapid circulation; by this means greatly increasing the heat of their little bodies, and enabling them to meet, without injury, all the changes of temperature to which they are subject in their passage through the air. The better to fit them |