There are very few things that Helen Keller experienced which scared her according to her autobiography, The Story of My Life. She had the extraordinary ability to learn from everything - from "life itself."(Ch 7)
In chapter 10 Helen is about to realize one of her dreams "to touch the mighty sea and feel it roar." She has no prior knowledge of the ocean, only her understanding from a book she has read called "Our World." Helen has lived "inland" without even "a whiff of salt air." She is fascinated by the images it has conjured in her mind. Helen and Ann spend some time by the sea and as soon as she can , she is in the water feeling the buoyancy. However, "ecstasy gave place to terror" as she is pulled under by the water which she describes as a "strange, all-enveloping element."
After Helen is thrown back to shore and safely into Ann Sullivan's grasp, she is as ever, quick to recover from her ordeal. From then on, the sea never loses its allure for Helen.