1051. In the act of germination the skin or outer covering of the seed, having been softened by water, cracks; and this allows the embryo, which has had its vital force excited by warmth, to swell, or, in other words, to expand and separate the particles of concentrated carbon of which it principally consists. The carbon thus expanded has a great affinity for oxygen, which it abstracts, partly from the water which it decomposes, and partly from the air, the hydrogen and nitrogen thus set free also appearing to combine with the carbon of the seed. A sweet mucilage is now formed, in which are found numerous vesicles or incipient cells, which are the rudiments of vegetable tissue.
