As usual, Parabola is exactly right. I owned one of these for several years.
The 84 refers to the bore diameter, so 84 bore equals about .390" from memory. There was no extractor as the paper case was meant to be burned up when fired. Often the needle is broken or too short, burnt and corroded by combustion. They date from about 1850 until about 1870 or so, and longer in Continental Europe.
W. Richards of Liverpool was a big retailer and many of their guns went abroad on the ships leaving Liverpool.
HB
