In church today we sang "Wondrous Love," an American hymn whose harmonies surround the tenor line, rather than supporting the soprano.
(It's 439 in the 1982 Hymnal.) I believe this is the "shape-note" harmonization I learned about from
Anonymous Four a while back, and it's fascinatingly different from other kinds of harmony. As the singers move from the first verse, sung in unison, to the harmonized verses, the voices spread out in both directions, like a river rising along both banks. It seems to come from the gut, and really, well,
swells.