Hi Nic,
I was going to comment when you put this on w/f's.com, but I wasn't convinced that the pattern was Webb's 'Fircone'. Unfotunately, the small picture profile does give that impression, but when you blow it up it loses the detail of the moulding.
When I first saw your photos I thought T. Webb, but which pattern? I've checked Steve Leslie's reference just to try and stimulate the ol' grey cells - but that hasn't helped. The shape of the bowls that you have do not conform to the range illustrated in the Lesley Jackson article in the Glass Association Journal, vol 5, 1997 - page 51. This doesn't necessarily mean that yours aren't, just that it hasn't been proved conclusively.
Let's see if anyone here has the information that you need........
Cheers, Nigel