All that can presently (June 2025) be gleaned about Augusta Phelps from sheet music covers and by Internet searching is that she was presumably an American actress/singer who has been featured on 3 works published between 1909 and 1910.
She had two mentions in Variety (December 1910) to whit:
The olio features had for a beginning three songs by Augusta Phelps which just barely passed; her style of working being all out of accord with the requirements of burlesque audiences. She has a fair voice but her "delsart" is poorly managed and entirely ineffective.
and
But the effects were pleasing and the women principals, the Misses Harris, Campbell, Davis, Aldah. Chrystie, Augusta Phelps and Helen Lawton, all changed frequently enough to keep pace with the general scheme of color and clothes.
Her portrait on the left is taken from All Aboard For Monkey Town (1910) music by George W. Meyer, words by Jack Drislane and published by F. B. Haviland Publishing Co. Inc., New York, USA.
Surfers are welcome to contribute any further information about this performer.