Friend of the Earth; pen name of Willimina Leonora Armstrong) (August 14, 1866 – November 2, 1947) was an American physician, writer, and lecturer.

She is best known for her book Incense of Sandalwood (1904)[1] and stories of India written in collaboration with Will Levington Comfort and published as Son of Power (1920).

[4] In 1887 she went to India as a medical missionary and served with her older sister, physician Saleni Armstrong-Hopkins.

[5] She wrote eighteen stories of India under the pen name Zamin Ki Dost published in collaboration with Will Levington Comfort as Son of Power.

[9] Willimina Leonora Armstrong died in 1947, and is buried at Glen Haven Memorial Park, Sylmar, California.