Thanks Jindrich,
Sorry for the delay in replying, I have been waiting the return of my Hi Sklo book which has been out on loan. The book has been returned now and I can see what you mean with regard to the Machovska vase which is also featured on the back cover. I think I should have included a side on photo which will show that my vase is very bulbous around the middle, so here it is from that angle.
Bryn