Bach and Equal temperament, or Bach and Well temperament?

[Vinny_Samarco@ima.connections.com]

Hello List,
     Well I'm back after a long absence.  Besides studying piano
tuning, I am a music History teacher and have been writing and
researching a college-level course for a number of years.  
I had always read that Bach tuned in equal temperament. 
Recently, a former tuning teacher from PHTC told me that Bach
tuned in well-temperament, not equal.  
First of all, Could someone tell me what is well-temperament? and
Secondly, could you tell me hhow you know that Bach did not tune
in equal temperament.
     Here is a quote from a booklet accompanying a recording of
the Wtc.


"The only vague testimony we have on the subject comes from his
obituary written by his son C.P.E. Bach, and his pupil J.F.
Agricola.  where it states that in the tuning of harpsichords he
achieved so correct and pure a temperament that all the keys
sounded pure and agreable.  He knew no keys which because  of
impure intonation, one must avoid"

Now, that is all I have ever seen on this subject. 
     Since I want to teach my students correctly, if any of you
have more insite and information on this subject, i would love to
hear from you.  
     Because I only have access to the internet through e-mail,
since I live in a remote location, I can't browse or download
from the net.

     Thank you very much for any assistance you can give me.

               Sincerely,
               Vinny Samarco