Yes, dig young'uns, dig. I would say that that London gave up the ghost earlier & sourced the Birmingham mechanics, who had well established rough tube sourcing lines to Liège. 1st, just rough tubes finished by Birmingham mechanics then probably something closer to finished tubes. One might look @ the British import laws to see if the U.S. of A. patterned their >>rough tube<< verbiage(reduced rates for >>rough bore tubes<<) after the Brits. More than likely the realization occurred in the early 1880s?

Cheers,

Raimey
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