Update : This old L.C Smith maker of Baker 10 gauge pre 1884,
push the front trigger forward to open breach.
after much inspection and measurement I fired both barrels with the RST-10 ga, 2 7/8 length, 1150, 1 1/8 oz #8 shells, What a rush-
I'm hooked on these really old ones, It was a BLAST pun intended !

Richard