Miss Beecher's Housekeeper and Healthkeeper / Containing Five Hundred Receipes for Economical and Healthful Cooking; also, Many Directions for Securing Health and Happiness

by Catharine Esther Beecher

The bones are covered with a thin skin or membrane, filled with small blood-vessels which convey nourishment to them.

Where the bones unite with others to form joints, they are covered with cartilage, which is a smooth, white, elastic substance. This enables the joints to move smoothly, while its elasticity prevents injuries from sudden jars.

The joints are bound together by strong, elastic bands called ligaments, which hold them firmly and prevent dislocation.

Between the ends of the bones that unite to form joints are small sacks or bags, that contain a soft lubricating fluid. This answers the same purpose for the joints as oil in making machinery work smoothly, while the supply is constant and always in exact proportion to the demand.

If you will examine the leg of some fowl, you can see the cartilage that covers the ends of the bones at the joints, and the strong white ligaments that bind the joints together.

The health of the bones depends on the proper nourishment and exercise of the body as much as that of any other part. When a child is feeble and unhealthy, or when it grows up without exercise, the bones do not become firm and hard as they are when the body is healthfully developed by exercise. The size as well as the strength of the bones, to a certain extent, also depend upon exercise and good health. So also they depend on the food, for fine flour is deprived of the materials that form bone, and growing children often have weak bones from having this for common food.

The chief supporter of the body is the spine, which consists of twenty-four small bones, interlocked or hooked into each other, while between them are elastic cushions of cartilage which aid in preserving the upright, natural position. Fig. 59 shows three of the spinal bones, hooked into each other, the dark spaces showing the disks or flat circular plates of cartilage between them.

Fig. 59.

The spine is held in its proper position, partly by the ribs, partly by muscles, partly by aid of the elastic disks, and partly by the close packing of the intestines in front of it.