A friend lent me an old book that had a section on Hide Glue that he thought I might be interested. I read the part about making a glue brush from a piece of basswood. I thought they meant the inner bark as illustrated in Hide Glue-Historical & Practical Applications illustrated below.
But the book said a piece of basswood, so I thought I would rebuke this with a simple test. I found a piece of basswood and using a small froe [made by Blacksmith Brian Westover] and split out a piece of wood so the grain would be straight. I then used my coffin smoother and spokeshave to round the wood into a proper shape.
Then according to directions ‘soak end in water for 2 to 3 days’, which I did replacing the water every day as some was soaked up by the basswood. After 3 days I took the wet piece of basswood and with a hammer smashed the ends, the hardy-hole anvil worked great. As I was pounding water was squirting out the ends, which I carefully removed from the hammer and anvil when finished.
To my surprise it delaminated and turned fibrous much like the inner bark does when softened by dry pounding. It hardens up when dry but softens again when soaked in water. As it wears down new fibers can be made by soaking and pounding again. Learn something new every day.