Just procured (via eBay) a Wilkinson's soda bottle in neat condition. Probably pre-dates the 40's but I'll leave that to the experts.
The text imprinted on the bottle reads:
W.A. WILKINSON
REGISTERED
(image of unicorn)
TRADEMARK
SODA WATER MANUFACTURER
NORTH SHIELDS
UPDATE: 30.03.06
Site visitor Dr Jim Rickard comments:
"I have looked at the photo of the bottle you bought on ebay, this bottle is found on late Victorian and Edwardian rubbish dumps from Blyth to Newcastle and Sunderland. It dates from around 1900 and was used in great numbers, it is probably the easiest to acquire bottle from Wilkinson. I have a broken example of a variation of this bottle that has the words "1/2d deposit charged on this bottle" embossed on the rear. a reminder that these bottles had deposits and would have been used many times before finally being thrown away (sometimes you can see a lot of wear on the base to prove this)."