This is David Marks and Richard Kammann's _The Psychology of the
Psychic_ (1980, Prometheus Books).  Essentially, it's an attempt by
these two researchers to determine if purported psychic phenomena were
real.  They looked into the allegedly psychic feats of Uri Geller and
the Amazing Kreskin, and also did a replication of the SRI remote
viewing experiments.  Contrary to Riley's claim that the book was
intended from the start as a hatchet job, they were open-minded about
whether the results would be positive or negative.  In fact, at first,
they thought that the remote viewing experiments were successful and
they were quite excited about this.

   Also, what is muscle reading?  (In the above context, it sounds like
   a form of subtle communication between hoaxsters.)

If you ever saw any of the old Late Night with David Letterman shows
that had on ``famed Russian psychic Lev Schneider'', that was an
example of very clumsy muscle-reading.  Essentially, in a trick that
involves the use of muscle-reading, the psychic has someone who is not
a confederate hide something (e.g. Kreskin would have them hide his
pay check).  The psychic then asks for a volunteer, also not a
confederate, who knows where the Maguffin is hidden and takes him or
her by the hand and proceeds to the correct location.  The way this
works is that the volunteer unconsciously resists, ever so slightly,
going in the wrong direction, and will tend to instinctively pull the
``psychic'' in the right direction.  Hence, the name ``muscle
reading'': a good muscle reader can feel the slight tensing and laxing
of the muscles and will move in the correct direction.  There is a
real continuum of skill here.  The Amazing Kreskin would apparently
hold onto one end of a handkerchief and have the volunteer hold onto
the other when he would find his pay check, quite a feat.  On the
other hand, so to speak, the aforementioned Lev Schneider would firmly
clasp both of his hands on the arm of the volunteer, which is pretty
lame.

The interesting thing about Marks and Kammann's book is that were able
to figure out how most of the tricks were done and, in many cases,
explicate how psychic performances make use of normal, but sometimes
subtle, aspects of human behavior and psychology.  It's a fun book
and, given that, unlike a professional magician like Houdini or Randi,
they did not know the standard tricks ahead of time, it reads a bit
like a detective story, as they observe each purportedly psychic
phenomenon and then try to determine how it might be done by
non-psychic means.