Hi Greg ,
Thanks for that ,its always interresting to hear of other peoples research on items they have , your reference to sealed Ravenscroft examples in this form is new information to me, though I must admit bottles and flasks have not been as major an interrest as the drinking glasses are to me ,the recent Bonhams Items if I remember correctly was in the Hartshorne sale I think ,the same one illustrated in Bickerton ,it has been the opinion of quite few for some time now that many of these flasks and that 1 in particular( I think the low selling prices reflected this thought) are not dated correctly and in fact could well be much later,in the style of 17thc examples,I have heard that Scandinavia was a possible place of manufacture for these later ones , so your contact with Oslo would have been interresting,I must say I am more convinced with your bottle though.
Cheers ,
Peter.