But the egg, what of that? Can we describe its nature and construction in a way sufficiently clear for our readers to understand? Let us try:--it is like a series of cases or envelopes, one within the other; the outer one only, which is the last formed, being hard and unelastic, that is, it will not stretch or change its shape. Like the shells of some fish, and other testaceous animals, it is composed of carbonate of lime, which the animal has the power of secreting, as it is called, from its food. Hens sometimes lay soft eggs, without a shell; this shews a deficiency of the secreting power, or a want of the necessary material, and may generally be remedied by mixing some chalk with the food, or scattering it about the yard. Next to the shell is a skin called the _membrana putaminis_, that means the membrane or skin of the shell; it has also a Greek name--_chorian_; it is divided into two layers, which separate at the larger end, and leave a space called the _vesicula aëris_, that is, air vesicle, or little bladder; this contains the air necessary for the chick to breathe before it chips the shell. Enclosed in this membrane is the _albumen_, or white fluid, sometimes called the _glair_, from the Latin _glarea_; in the same language _albus_ means white; and our readers who live in Albion, so called from her chalky cliffs, ought to see at once from whence we derive the word _albumen_; the little chords by which this bag of fluid is suspended are called _chalaza_; this word comes from a Greek root, and has reference to the connection between the suspending chords and the germ, or spot, in which is the vital principle. We now come to what may be called the provision bag, because it encloses the yolk, which serves as food for the animal in embryo; it is called _membrana vitelli_, or the skin of life. Thus our examination of the egg has brought to view the three great necessities of all existence--_protection_, the shell and albumen; _nutrition_ or food, the yolk; and the _vital principle_, to understand the nature of which has puzzled the greatest philosophers that the world ever saw. It is said in the Scriptures that God breathed into man the breath of life, but what this may be we can none of us tell; it is given to us and we _live_, it is taken away from us and we _die_; and so do all God's creatures, which by Him, and Him alone, live, and move, and have their being. Man can do many wonderful things, but he has not yet been, nor will he ever be, able to make an egg, much less to produce a chick from it.