Heinrich Barella expired in 1893 so by the time this example was peddled, his son Max Barella and other Nephew August Barella were doing the sourcing for their retail outlets in Berlin(W8 - Französischestraße 25/26) & Frankfurt. I think the advertising on the tube of "H. Barella Berlin Könglich Kaiserlich Hofbüchsenmacher" was used as they touted their clients like the King of Italy & Romanian as well as the Tsar of Russia and other affluent folks in Austria, Indian, North Africa & Turkey. In 1867 he divulges that he was sourcing tubes in the raw state from Belgium and components from England to "make by hand" in his shop his upper rung offerings peddled from Behrenstraße 29. His nephew Heinrich Leue, along with Fritz Timpe, advertised as Kaiserlich Französische Hofbüchsenmacher till they split the sheet in say 1876?
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Kind Regards,

Raimey
rse