8) Jim and Rosy could elope; 9) Jim gave the powder not to Rosy but to her father.

8) Jim and Rosy could elope;
They might have considered eloping if they were deeply in love and unable to get married with Mr. Riddle's consent. However, this was not the path they took in this story.

9) Jim gave the powder not to Rosy but to her father.
This is a crucial plot point that explains the misunderstanding. Jim intended the drug for Rosy, but it ended up with her father, leading to the tragedy when the father mistakenly administered it to his daughter.