@Rodger Willows 'pre-1911', yes, but even the latest possible date could be a little earlier than that because that wonderful tank top legend layout still inclues the term 'PATENT'. @gieorgijewski posted an insightful discussion here regarding the expiration of patent protections in relation to Primus stoves, and how that linked to changes in tank legends. And indeed examples of this discus tank top design are in the gallery both with and without the designation 'PATENT. More to the point those without 'PATENT' in the legend include examples not just with the 1911 'A' coding, but also without the 'A' date code. So the 'PATENT' wording itself had to have been dropped pre-1911, meaning those with 'PATENT' must be pre-1909/10.
@igh371 Thank you very much for your input and the link - quite insightful indeed! So, perhaps a little older than I'd considered!
