How things were built "back then"

As you know we are remodeling an older farm house to rent, to allow us to afford to finish a new farmhouse, to live in, on 12 acres.
Work on the old farmhouse has been going along nicely. we have replaced the entire floor structure in one bedroom, off the garage. We have now moved on to a seriously dilapidated and rotten floor in the living room. The Floor was collapsed, we think, because of a cast iron woodburning stove. (that was supposed to sell with the property but didn't). This room is what we think comprised the entire original home in 1920, and as is the norm, was added onto repeatedly since then.  The newspapers in my previous post were beneath several layers of linoleum, above the original hardwood flooring (tongue and groove, fastened with square nails)
The layers went from barn wood subfloor and railroad tie floor joists, to the original layer of hardwood. then tar paper backed linoleum type product (added after 1955), then a double layer of cardstock paper, more linoleum, a layer or tarpaper, and even more linoleum, then OSB subflooring (obviously a later renovation) carpet padding and carpet. There may have been 4 layers of linoleum, I can't recall, but definitely at least 3 layers! It was a lot of work getting all that out, and gingerly removing the hardwood, to hopefully refinish and reuse in another room.

Saving the hardwood will be a neat adventure, as we had hoped to do so on our current home, but it turned out that it was pine, and much too damaged to try to use. I am hoping to clean, and lightly sand the flooring, and consider if stain is needed before finishing it with poly urethane.
The pillars and joists were an interesting discovery.
The wood used for the original joists are milled lumber (very rough) and perhaps rail road ties. Or some similar beams. The pillars were constructed by using stacked flat stones.

 


We plan to add a new footer and foundation wall and rebuild the floor structure completely. we are debating how much of the original structure to leave behind. And perhaps repurpose some of the old pillar stones somewhere at the new house, as a "keepsake" of the older history of the property.