Ed.
The good news is the barn is over 100 years old and still standing. Says something about craftsmanship in that time.
The bad news is Eastern hemlock, as a structual species, is suspect. Yes, it is used sparingly in some timberframe projects even today.
I would strongly recommend you find a local timberframer or National Forest Ranger with the knowledge to survey the barn in detail to report on it's condition and strength. Armed with a good survey you can make the decision to save it, move it or burn it. Most Eastern Hemlock today is a pulp source for remanufacture into other wood based products. Without good information the decision cannot be reasonalby made.
Had I known about the barn prior to my return home in VA this evening I could have taken a cursory pre-check this afternoon. I drove within 30 miles of the site on my way down I81.
Good luck,
Emmett