shifting the tail

["Bonnie Blackwell, x 3332" <bonn@qcvaxa.acc.qc.edu>]

for those  of you having a hard time visualizing this idea, try this.
go to your local swimming pool.  float in a horizontal position.
o----------|
try lifting your head simply by contracting the muscles in your neck.
the effect is to swing the whole body into a vertical position.
similarly tightening the bum muscles (in an attempt to squeeze a dime
between your cheeks) will raise the feet to a near horizontal position.
it obviously do not work in quite the same way on land, but the principles
are the same.  the body is a giant lever balanced about the fulcrum, the
centre of mass.
b

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Bonnie Blackwell,                               bonn@qcvaxa.acc.qc.edu
Dept of Geology,                                (718) 997-3332
Queens College, City University of New York,    fax:  997-3349
Flushing, NY 11367-1597