  Modifications on a recently introduced fast dynamo operator by Chiconne et al
[Comm Math Phys 173, 379 (1995)] in compact 3D Riemannian manifolds allows us
to shown that slow dynamos are Lagrangean stable, in the sense that the
sectional curvature of the Riemann manifold vanishes. The stability of the
holonomic filament in this manifold will depend upon the sign of the second
derivative of the pressure along the filament and in the non-holonomic case, to
the normal pressure of the filament. Lagrangean instability is also
investigated in this case and again an dynamo operator can be defined in this
case. Negative curvature (Anosov flows) dynamos are also discussed in their
stability aspects.
