Thank you both for your input. I have been reading on
http://www.pressedintime.com/davidson.htmabout Davidson. I thought this excerpt was interesting too:
"Sheilagh Murray in her book The Peacock and the Lions tells a very interesting story regarding the crescent shaped boats. These moulds had been ordered from Germany, but the ship had been wrecked on the Black Midden rocks at the mouth of the Tyne. Four years later some of the moulds were recovered, but had become so corroded that bases were made in England. You can see the differences in workmanship in the piece where the sides of the glass are German in a bold fashion, whereas the bases are far more detailed with the traditional star design"
According to this site paper labels were introduced after 1909 and I don't know whether the reg. no. would still have been use - I guess it would if the same moulds were used. Anyway if anyone knows when this amber colour was being made ----- (My piece has the traditional star design on the base)
Thanks again