Elasticity belongs essentially to this system. This property is very
evident, 1st, in the fibro-cartilages of the ears, when we bend them;
2d, in those of the nose, when twisted in various directions; 3d, in
those of the trachea, when we compress them, or after having cut them
longitudinally, we separate the edges of the division, as is done in
tracheotomy, when the object is the extraction of a foreign body. It
performs an important use in the kind of vibration which is made in
the first in the perception of sounds, in the second in the production
of the voice; 4th, it is in virtue of their elasticity, that the
articular fibro-cartilages serve as a kind of cushions which favour,
by contracting and expanding, the motion of the osseous surfaces to
which they correspond; 5th, that those of the vertebræ in particular,
flattened during the day, re-act during rest, and thus make the
stature in the morning something more than it is in the evening; 6th,
finally in the sliding of the tendons upon their fibro-cartilages, the
elasticity of these last favours the motion in an evident manner.
This elasticity of the fibro-cartilages is united to a remarkable
suppleness; they bend in all directions without breaking. By the first
property they resemble especially the cartilaginous system; by the
second they approximate the fibrous. It is not astonishing that being
intermediate to these two systems in their texture, they should be so
also in their properties.