How did water most help to shape the Grand Canyon

In "The Train From Rhodesia", the young woman carries around a great deal of shame that can be attributed to a certain specific situation. Her husband has given her an item made by a native artist as a gift. The little amount he paid for it makes the husband proud, but it has the opposite effect on the young woman. She feels like she's being an accomplice of the poor treatment of the artist, who is only accepting the low price and selling-off his work short, out of sheer necessity. The situation makes her feel like she's wrongfully taking advantage of someone.

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