In Chapter 7, why wasn't the letter Scout and Jem left in the tree delivered?
In Chapter 4 of Harper Lee's To Kill a Mockingbird, the novel's young narrator, Scout, is rushing past the mysterious, somewhat foreboding Radley house on her way home from school. Something in one of the large old oak trees on the Radley property caught her eye. Upon investigating, Scout discovered that somebody had put sticks of chewing gum in a knot-hole in one of the trees. With that discovery, a game of sorts develops involving Scout, her older brother Jem, and their friend Dill. The children begin to find items in the knot-hole on a regular basis, including old pennies, a ball of twine, figurines carved out of soap, and, finally, an old pocket watch.
The children continue to be mesmerized by the items they find in the knot-hole of the oak tree on the Radley lawn. Most importantly, they are understandably curious about the identity of the person placing those items in the tree. They speculate about the identity of that person until Jem decides to write a letter to the mysterious individual thanking him or her for the gifts that the two decide must be intended for them. Jem and Scout both sign the letter and eagerly anticipate a reply. As Scout describes the chain of events, however, it is clear that their plan has encountered an obstacle:
"Next morning on the way to school he ran ahead of me and stopped at the tree. Jem was facing me when he looked up, and I saw him go stark white. 'Scout!' I ran to him. Someone had filled our knot-hole with cement."
The "someone" who had filled the knot hole with cement was Nathan Radley, Boo Radley's father. When questioned by Jem as to the reason for filling in the hole, Nathan explains that it was necessary because the tree was dying. The tree, however, was not dying. Nathan Radley was merely trying to contain the actions of his son, Boo, who was responsible for placing the various items in the tree for the children to find. That is why Jem and Scout's attempt at thanking whoever was placing gifts in the knot hole was unsuccessful.
In Chapter 7, Jem and Scout decide to write a thank you letter to the anonymous person who has been leaving them gifts in the knothole of the Radley tree. The following day, Jem runs over to the tree, only to discover that the knothole has been filled in with cement. Jem is both shocked and disappointed that the hole has been filled in. The next day, Jem sees Nathan Radley and asks why he filled the knothole with cement. Nathan Radley responds by telling Jem that the tree is dying, which is why he needed to fill it with cement. However, Jem realizes that Nathan lied to him and Atticus confirms that the tree looks healthy. Nathan Radley more than likely was attempting to stop Boo from communicating with the children, which is the real reason why he filled in the knothole.
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