Joe Marsala, "Topsy" 1942

Adele Girard may have been the first real "swing harpist."  There had been a couple of other instances of harp showing up on jazz records, but Girard appears to be the first harpist to be a regular featured soloist in a swing band.  Here's a good example of her sound recorded live in 1942 with Joe Marsala's band.

SWING THAT HARP