is articulated, is a highly-flexible column, capable of moving in any direction which may be necessary, and during its movements forming a series of elegant curves, so truly described by the ancients as the serpentine line of beauty; these curves also serving to keep the head within a line drawn from the top of the head to the ground, called the centre of gravity. Were it not for this provision, the erect position could not be maintained for even a short period. In erecting a column, the builder will take care to make the base broader than the apex; but the contrary is the case in the human figure. The want of this peculiar elasticity is the reason why artists have never succeeded in constructing statues which would stand without a pedestal, and such would also be the case in the human conformation were it not for the action of the muscles by which the spine is supported.
As we have already described, the clavicles or collar-bones exercise considerable influence in expanding the shoulders and chest; and this is an essential provision, for the purpose of counteracting the traction of the pectoral muscles, or those of the chest, whose tendency is to pull the shoulders forward, and by their action diminish the size of the thoracic cavity. The clavicles, however, would form
