The constituent elements of the body are not found in the same
relative proportions at different periods of life, or in different
individuals of the same age. In middle life the muscular system
predominates, and the body is remarkable for the compactness of its
fibres, its strength, and its power of endurance.
In the child there is an excess of fluids, which renders the body
more plump and round and the form beautiful, though more frail and
delicate than at a later period. In advanced age, the soft tissues
become greatly diminished, and the form wrinkled and wasted.