In response to my inquiry about my 12 with the successor company of H. Atkin which is in possession of Atkin's records, I received the following:
"It is described as a 12 bore top bar A+D ejector 27" barrels and is No 2 of a pair. Built for Howard Erie and completed on 25/2/1938."

What is meant by "top bar"? Hallowell is silent as to this term. Gil