The Demoulin & Berger Interpretation of LCT
¥Degeneracy:  Motions parallel to B do not directly affect apparent motion of magnetic features.
¥Apparent horizontal motion ULCT is from a combination of horizontal motions and vertical motions acting on non-vertical fields.
Flows parallel to B donÕt affect the motion of  Magnetic Features.  Therefore we
consider only flows normal to B, and set
v¥B=0.  This constraint, plus the Demoulin & Berger interpretation,
leads to  this solution for v^ and vz: