In Chapter 7, Helen uses an extended simile to compare a child's mind to a shallow brook:
[Miss Sullivan] realized that a child’s mind is like a shallow brook which ripples and dances merrily over the stony course of its education and reflects here a flower, there a bush, yonder a fleecy cloud; and she attempted to guide my mind on its way, knowing that like a brook it should be fed by mountain streams and hidden springs, until it broadened out into a deep river, capable of reflecting in its placid surface, billowy hills, the luminous shadows of trees and the blue heavens, as well as the sweet face of a little flower.
The first simile here is "a child’s mind is like a shallow brook." Helen writes that such a brook "ripples and dances merrily" and reflects whatever it comes into contact with. The second simile says that a child's mind, much like a brook, "should be fed by mountain streams and hidden springs" until it can become a "deep river" capable of producing more nuanced reflections. In other words, much like a brook that deepens into a river, a child's mind will, with proper education, become a place of deep reflection and contemplation. The use of water as a symbol for the human mind and spirit appears frequently in the memoir, and here Helen credits her teacher with knowing the nature of her own and other children's minds.
This simile also shows Helen's appreciation for education and reflection. She thinks more deeply about these things after attending the Perkins Institute. The generosity and perseverance of figures like Miss Sullivan and Dr. Bell have a great impact on her, and she continues to express her gratitude for them throughout the text. This simile represents one of many little odes of gratitude to her teachers and reveals the depth of impact her teachers had on her mind. It also reinforces the novel's recurring natural symbolism and makes an association between nature and the human mind.
Throughout The Story of My Life, Helen describes the joys and difficulties of learning how to communicate with other people. In Chapter 9, she uses a simile to convey her comparative isolation from other children:
We had scarcely arrived at the Perkins Institution for the Blind when I began to make friends with the little blind children. It delighted me inexpressibly to find that they knew the manual alphabet. What joy to talk with other children in my own language! Until then I had been like a foreigner speaking through an interpreter.
Prior to learning sign language from her teacher Anne Sullivan, Helen felt "like a foreigner speaking through an interpreter." This simile shows her feelings of otherness compared to people who have the ability to see and hear. However, when she arrives at the Perkins Institute, she is "delighted" by the fact that she can speak to children her own age. They have all lost their sight and have had the same education in the manual alphabet. Helen describes the alphabet as "[her] own language" and seems not only comfortable but joyful when she uses it.
Helen frequently uses similes to make her experiences more accessible to the average reader; her story is extraordinary, but she tries to make it understandable. Many people experience feelings of otherness or foreignness during adolescence, and this simile communicates the distance between herself and other people prior to being around similarly-abled people at the Perkins Institute. Despite her initial feelings of isolation, she learns to communicate and connect with others.