Thanks for the additional info, Frank.
I have also had some extra snippets very recently from another source and this begins to tie together quite well.I would appreciate the following comments and images being viewed solely as part of this message and not copied or used elsewhere.
(Although the evidence is beginning to make sense, much of the detail still needs to be sorted out and anything taken out of context could be misleading. Also, I might change my mind on some of my current assumptions or conclusions!)
It is most likely that the "Leamington" referred to in Dave Moir's details was actually the "Lemington" (without the "a") that Adam D mentioned. This is a place [not marked on general UK road maps] adjacent to Newcastle Upon Tyne, where there was a very old glassworks which eventually was owned by Sowerby. Frank Eisner being at Lemington is backed up by a marked and dated item - sorry, but details not yet available for general sharing.
Dave M's commenyt about Frank Eisner also being at Waterford ties in with something else. I had already known for some time of a paperweight with very good etched details suggesting Frank Eisner worked for Waterford (but location may not have been the actual Irish place?) in the late 40s or early 50s.
Rgarding the type of "Eisner flower" weight we are talking about, these are not (usually?) "Bohemian style flowers in a vase". They are like those shown in my Ysart Glass conference images - some of which are shown below.
Two examples (profile only): http://i3.tinypic.com/vxozsy.jpg
These two show a typical form of the ground and of the flowers. The ground can also appear in other colours or even in clear glass. Most often the ground is decorated with scattered coloured bits.
The weight on the left of the above image was a "must have" since it has one whole cane (albeit misshapen) and some part canes which match to Ysart work! The weight also has a blue-purple tint to the dome, similar to that seen in some "1930s" Paul Ysart weights and various weights from early Vasart days. The Ysart cane is shown here:http://i3.tinypic.com/vxp1g7.jpg
I bought two "Eisner" flower weights from the same source, one of which was a typical example. The other was rather different:http://i3.tinypic.com/vxp1rm.jpg
Three of the flowers are of the same general form, bu the the fourth has many more petals. There are leaves, which is not a regular feature and the ground is a mottled green-and-white which is also not typical.
All examples I have viewed under UV have shown the same reactions - the same as early Ysart weights. But this does not prove they were made from the same glass as the Ysarts used.
All it means is that the UV reaction suggests a soda-lime composition. Very similar results can be seen for various items from various countries. I have not therefore placed much reliance on the UV reactions of these "Eisner" weights to suggest attribution, except to say that they have all been similar to one another. It's the other evidence that is needed to confirm or deny things.