Gayle,
MJ Research manufactures a Thermocycler with options for insitu work
called a PTC-200 DNA Engine.  It is really a remarkable machine in that
one purchases separate "alpha units" that hold either tubes or 2 columns
of 16 slides for in situ PCR.  I have used this instrument for years for
traditional PCR reactions but have not tried the insitu alpha unit.  I
can say that my experience with the PCR cycler has been excellent and in
fact bought my third unit when I moved to a new lab.
MJ Research number is (888-735-8437) and web site is located at:
www.mjresearch.com.
Valerie DeGroff
Ohio State University