Among her many accomplishments not the least astonishing is her power for appreciating music, which she “hears” by placing her hand lightly on the piano and receiving its vibrations. It occurred to Doctor Louis Waldstein, a pioneer in the study of subconscious mental processes, that quite possibly her appreciation of music was connected with latent memories of music she had heard before her illness. To test this theory he obtained from her mother copies of two songs which had often been sung to Miss Keller as an infant in Alabama, but which she had not heard since. These he played in her presence, with a remarkable effect. She became much excited, clapped her hands, laughed, and communicated: “Father carrying baby up and down, swinging her on his knee! Black Crow! Black Crow!” It was evident to all present that she had been drawn back in memory to the surroundings of her infancy. But no one knew what she meant by the words “Black Crow,” until her mother, in answer to a letter of inquiry, explained that this was the title of a third song which her father used to sing to her. “What you wrote,” commented Mrs. Keller, “interested us very much. The ‘Black Crow’ is her father’s standard song, which he sings to all his children as soon as they can sit on his knee. These are the words, ‘Gwine ‘long down the old turn row, something hollered, Hello, Joe,’ etc. It was a sovereign remedy for putting them (the children) in a good humour, and was sung to Helen hundreds of times. It is possible that she remembers it from its being sung to the younger children as well as herself. The other two I am convinced she has no association with, unless she can remember them as she heard them before her illness. Certainly before her illness her father used to trot her on his knee, and sing the ‘Ten Virgins,’ and she would get down and shout as the negroes do in church. It was very amusing. But after she lost her sight and hearing, it was a very painful association, and was not sung to these two little ones” (the younger children). Almost by itself this impressive bit of evidence justifies Doctor Waldstein’s unhesitating declaration, as set forth in his interesting book, “The Subconscious Self”: