By this action, the highly elastic axis
must be bent at the lower extremity, where it is naturally slightly curved; and I imagine it is by this elasticity alone that the zoophyte is enabled to rise again through the mud.
The motion of the profile is described by functions [alpha](t), representing the rotation around the elastic axis TR, and H(t), denoting the vertical displacement; see Figure 2.
alpha]H] denote the static moment around the elastic axis TR, the moment of inertia around TR, the mass of the profile and the stiffnesses of the profile elastic support.
i], i = 1, 2, are the coordinates of the elastic axis [x.