Thixotropy : is sometimes
offered as an explanation as to why the blood of St.
Januarius allegedly liquefies twice a year. Thixotropy is
actually a property that is exhibited by certain gels (semisoild,
jellylike colloids). A thrixopic gel seems at first to maintain its
shape and act and behave like a solid. However once subjected to
forms of disturbance such as shaking, it then flows freely and takes on
the properties of a sol or semifluid colloid.