Nice blog about Sacred Harp!
FYI, the book was first compiled in 1844 by Benjamin Franklin White, but shaped notes were invented in 1801 or 1803, I can't remember which. And this style of music existed in New England in Colonial times, though singing in the square probably originated later.
We have a singing convention at the end of September, 2 days, all day with potluck lunch at noon. Everyone come! No singing experience necessary.
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