That is a rightious old J. Stevens Arms & Tool Co. double. Up thru Catalogue No. 52 they made doubles using the demi-bloc construction method. They were offered with either "high Pressure Steel", Twist, Damascus or Krupp Fluid Steel tubes screwed into the mono-bloc. By J. Stevens Arms & Tool Co. General Catalogue No. 53 (circa 1911) they had gone to chopper-lump barrel construction.
I am fully & totally aware of the use of the term "Demi-Block" in reference to Chopper Lump construction. I am also aware of J Stevens use of Chopper Lump bbls. But re-read Researcher's post here & quit skipping the issue. These bbls "ARE NOT" chopper lumped. According to Researcher they were cataloged by J Stevens as "Demi-Block", ""BUT"" the bbls were "Screwed into the front of the block", that's not Chopper Lump.
My question was & is a pure & simple one, was the breech end of these bbls (Block) made in one piece ala Mono-Block, ""OR"" was it made in two parts, assembled & the tubes then screw in place. This would be a construction which would greatly resemble a chopper lump bbl which has been cut off & sleeved. I thought this was a fairly simple question, but no one seems able to fathom it.
PS; Researcher did use the term mono-block in his description of these early J Stevens bbls. What my question really amounted to was, "Were they built on true mono-block construction", or did he just use this term as a "Figure of Speech" like so many today refer to sleeved bbls as having a mono-block regardless of original construction type.