Page:Mrs Beeton's Book of Household Management.djvu/2119

Rh inflated, the breast-bone and ribs rise, the chest expands, and, with a sudden start, the infant gives utterance to a succession of loud, sharp cries, which have the effect of completely filling the lungs with air.

At the same instant that the air rushes into the lungs, the valve, or door between the two sides of the heart—and through which the blood has previously passed—is closed, and the blood taking a new course, bounds into the lungs now expanded with air, where it becomes oxygenated and made fit to nourish the different organs of the body.

What the key is to the mechanical watch, air is to the physical man. Once admit air into the mouth and nostrils and the lungs expand, the blood rushes to the remotest part of the body; the mouth secretes saliva, to soften and macerate the food; the liver forms its bile, to separate the nutriment from the digested aliment; the kidneys perform their office; the eye elaborates its tears, to facilitate motion and impart that glistening to the orb on which depends so much of its beauty; and a dewy moisture exudes from the skin, protecting the body from the extremes of heat and cold, and sharpening the perception of touch and feeling. At the same instant, and in every part, the arteries are everywhere laying down layers of muscle, bones, teeth, and, in fact, like the coral zoophyte, building up a continent of life and matter; while the veins, equally busy, are carrying away the debris and refuse collected from where the zoophyte arteries are building; this refuse, in its turn, being conveyed to the kidneys, is then excreted and leaves the body as urine.

All these—and they are but a few of the vital actions constantly taking place—are the instant result of one gasp of life-giving air. No subject can be fraught with greater interest than watching the changes which are wrought upon the living baby the moment the external air acts upon it.

The Stomach.—Digestion.—Next to respiration, digestion is the chief function in the economy of life, as, without the digestion and absorption of food, there would be nothing to supply the immense and constantly recurring waste of the system, caused by the activity of the vital processes, especially during infancy and growth.

In infancy (the period of which our present subject treats), the series of parts engaged in the process of digestion may be reduced simply to the stomach and intestines, and the liver, or rather its secretion, the bile.

The stomach is a thick muscular bag, connected above with the gullet, and, at its lower extremity, with the commencement of the small intestines. The duty or function of the stomach is to secrete a sharp, acid liquid, called the gastric juice, which, with a due mixture of saliva, softens, dissolves, and gradually digests the food or contents of the stomach, reducing the whole to a soft pulpy mass, the chyme. This passes into the first part of the small intestines, where it comes in contact with the bile from the gall-bladder and the pancreatic juice