sw imply a silent agitation, or a softer kind of lateral motion; as sway, swag, to sway, swagger, swerve, sweat, sweep, swill, swim, swing, swift, sweet, switch, swinge.
"A Grammar of the English Tongue"
Samuel Johnson
Yes'm, I'se got sw-e-et straw-ber'ies des f'om de coun-try!"
"Virginia"
Ellen Glasgow
1255-1258. This passage is a good illustration of the constant parallelism of word and phrase characteristic of A.-S. poetry, and is quoted by sw.
"Beowulf"
Unknown