On Wed, 14 Jul 2010 20:41:47 -0700 (PDT), Sonny wrote:

There's a good chance it's just stuck.

Thanks,
Will

That window pane unit is really heavy. That's a large window. It may
not readily move with gentle pressure, but you have to be careful with
whatever pressure you apply.

Will do. Careful, careful, and more careful.

If there are rubber spacers around the
sash unit, they may be flattened, some, at the bottom and they are
likely stuck down, also. Try running a thin knife blade around the
edges... see if you can feel something that would be contributing to
the "stuckness".

Mostly it won't penetrate at all. Around the bottom, it will go
thru half-way (only) in places.

To be on the safe side, tape the panes well, just in case one/they
break. Is there some small printing or a logo "tattoo" on one of the
lower corners of the panes, indicating tempered glass?

No. I checked all 4 corners.

I didn't see
any, in the pics. If there is no logo or printing, the glass is
plate glass and would break into dangerous shards.

The glass looks thin, like 1/8 " or less. When you look thru it at
an angle (maybe 30 degrees or less), the image is "rippled". Cheap
plate glass?

I took a tap hammer and a little block of wood to it to see if the
mounting might break loose a little. Nothin' shakin', but the spider
got very, very nervous. :-)

Looks hopeless?

Thanks,
Will