Jim Kelley wrote:

I think we both understand that light travels at a velocity which is
dependent on the medium through which it is travelling. You seem to
want to continue to argue about that, and to tell you the truth I can't
see much difference between that, and the kind of debate going on over
and over in this newsgroup.

This isn't the first time I've failed to communicate, and I'm sure it
won't be the last.

The sole point I was trying to make is that the letter c is just about
universally used, as far as I can tell, to mean the velocity of light in
a vacuum. That symbol is not generally used to mean the speed of light
in any other medium.

Roy Lewallen