All of the Anabaptists in Indiana trace back to Somerset County. So I do know a little about it and its history. I have ancestors from that community.

In PA, there was a lot more intermingling then there was in Indiana. People came out here largely to establish their own communities, in a way to get away from everyone else. Amish farmers came to Indiana, for example, to start Amish colonies. In our region there was a very strong distinction between the ethnic communities until maybe 40 years ago, and even now that past leaves its mark. The Lutherans of Western Howard County did not associate with the Scotch Irish to the north and east, the Dunkards and Amish remained in their own communities, etc.

Berne Indiana is a good example of this, where people of Swiss Background -Amish, Mennonite, Reformed- came and established a Swiss settlement that was to be and remains distinct and separate from everyone else around them.

Back to barns,

I measured this barn today. It is, in fact, 40x80 on the upper level, the drive bays being about 20 foot 6 inches wide, and the tie beams in the center bents spanning a full 20 feet.

Posts in the walls are 9x9, the center posts in the center bents are 9x11.
The tie beams are 9x10 to 9x11, the plates and purlins roughly 10x10
The sills of the upper level are nearly 12x12
All timbers in the basement level except the foundation sills are 12x12, the sills are slightly larger.

The spacing of timbers and bents to me seems to be somewhat exceeding good design principles, but it seems top have survived the past 150 years pretty well with most major issues being the result of late 'repairs' like replacing portions of the foundation with concrete, or modifications like cutting out the lower sills to allow entrance of wheeled vehicles or cutting out the girts to add additional doors and windows.

Two of the center bents had their uppermost tie beams cut out to allow a hay claw to move hay from the driving floor into the side lofts. This modification does not seem to have severely compromised the integrity of the structure (doubtless due to the triple tie beam arrangement in the center bents, and the fact that the centermost bent retains its upper tie.)

I inspected another very unique barn today. This barn is very unusual, as it did not begin its life as a barn. It was originally a timber framed house that was later modified to serve as a barn, a more modern solid brick house having been built near it over 100 years ago. The center frame is doubtless exceedingly old for this area.

I didn't get any pictures, but I'll be back there sometime in the next few days.

One interesting fact about this house frame, the corner posts were hewn out to solid 12x12 (I'm guessing) dimensions but the inside corner notched out so as not to intrude into the interior. I was not aware of this practice being in use in this area. But I have seen very few timber houses locally.