The main crimes committed in Part One (Chapters 1–10) are the kidnapping of Sis, Edmund's sister, the theft of the California gold, and the murder of Aunt Pru, Edmund and Sis's maternal aunt.
Five quotes from characters that show a connection to the crimes that were committed are:
1) "Sir, a few days ago, before my aunty disappeared, she said she was going to meet a man who might help her." (Chapter Four)
These words are spoken by Edmund to Mr. Dupin. The man that Aunt Pru meets, Mr. Peterson, ends up killing her in the mistaken belief that she is Mrs. Rachett (Edmund and Sis's mother). In the story, Aunt Pru and Mrs. Rachett are twin sisters. Basically, the "man" in the quote above refers to Aunt Pru's murderer.
2) "Unless someone else had a key, there was only one other way out: through the window of your room--to the window in the building opposite." (Chapter Four)
These words are spoken by Mr. Dupin to Edmund. Mr. Dupin's words indicate how Sis was kidnapped from a locked room in the tenement building.
3) "Not on her own. Of course not. She was forced." (Chapter Five)
These words are spoken by Mr. Dupin to Edmund as they search for Sis in the apartment opposite Edmund's own. Mr. Dupin deduces (from the pearl button found at the site) that Sis was kidnapped. This means that Edmund's sister did not walk the plank from one building to the other of her own volition. The pearl button and the wooden plank constitute evidence that Sis was abducted.
4) "In short, Edmund, the people your mother was consorting with, the man your aunt went to meet and who perhaps killed her, the ones who stole your sister--they are all one and the same." (Chapter Five)
These words are spoken by Mr. Dupin to Edmund. The plot bears out the truth of what Mr. Dupin (Edgar Allan Poe) says here. We later learn that Mr. Peterson was responsible for killing Aunt Pru and that Mr. Rachett (Edmund's step-father) kidnapped Sis while Edmund went in search of Aunt Pru. Both Mr. Rachett and Mr. Peterson worked together for monetary gain.
5) "Yes," Dupin agreed, laboring for breath, "no grown person could." (Chapter Eight)
This is a very short quote. However, Dupin's words here demonstrate his astute analysis that the thieves used Sis to steal the California gold from the Providence bank's vault. Sis was lowered down to the vault through a shaft that was no more than a foot wide. Mr. Peterson confirms Mr. Dupin's suspicions when he tells him that no grown person could have come down the shaft:
"It's far too narrow, isn't it? I'm fairly thin myself, but even I couldn't get through."
Also, another one of Sis's pearl buttons is found at the scene of the crime. It is identical to the button Mr. Dupin found in the apartment located opposite from Edmund's own.