A Treatise on Domestic Economy; For the Use of Young Ladies at Home and at School

_f_, is the _cheek bone_; _g_, the _upper_, and _h_, the _lower, jaw bones_; _i_, _i_, the _spinal column_, or back bone, consisting of numerous small bones, called _vertebrae_; _j_, _j_, the seven _true ribs_, which are fastened to the spine, behind, and by the _cartilages_, _k_, _k_, to the _sternum_, or _breast bone_, _l_, in front; _m_, _m_, are the first three _false ribs_, which are so called, because they are not united directly to the breast bone, but by cartilages to the seventh true rib; _n_, _n_, are the lower two _false_, which are also called _floating, ribs_, because they are not connected with the breast bone, nor the other ribs, in front; _o_, _o_, _p_, _q_, are the bones of the _pelvis_, which is the foundation on which the spine rests; _r_, _r_, are the _collar bones_; _s_, _s_, the _shoulder blades_; _t_, _t_, the bones of the _upper arm_; _u_, _u_, the _elbow joints_, where the bones of the upper arm and fore arm are united in such a way that they can move like a hinge; _v_ _w_, _v_ _w_, are the bones of the _fore arm_; _x_, _x_, those of the _wrists_; _y_, _y_, those of the _fingers_; _z_, _z_, are the round heads of the thigh bones, where they are inserted into the sockets of the bones of the pelvis, giving motion in every direction, and forming the _hip joint_; a b, a b, are the _thigh bones_; c, c, the _knee joints_; d e, d e, the _leg bones_; f, f, the _ankle joints_; g, g, the _bones of the foot_. The bones are composed of two substances,--one animal, and the other mineral. The animal part is a very fine network, called the _cellular membrane_. In this, are deposited the harder mineral substances, which are composed principally of carbonate and phosphate of lime. In very early life, the bones consist chiefly of the animal part, and are then soft and pliant. As the child advances in age, the bones grow harder, by the gradual deposition of the phosphate of lime, which is