I don't have all the information at hand. However...
 
the W. H. Greener co. is not related to the more famous W. W. Greener Co.
(I don't think)
The "Far Killing Duck Gun" is advertised and illustrated in the Johnson
Sporting Goods catalog c. 1888
 
I thought someone else would have answered your question by now. But, since
they haven't I'll look up the references tonight and post tomorrow.
 
If you'll send me a fax number I'll fax a copy of the catalog page.
 
 
Jim Barnes
U.S. Army Corps of Engineers
1222 Spruce St.
PD-AC
St. Louis, MO   63103
(314) 331-8863
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