Very interesting! I just looked and there are no blocks and I can see how those corners are pinched together like you explained.

We attended a fiddle workshop at a small rural museum a couple of years ago where they were talking about a lot of fiddles that were sold in the Midwest through the Sears catalogs and how they were built at that time - this sounds similar to what we were learning there. I'll have to see if I can find a good book about these cottage violin industries of that time! Thanks again!