What are the important objects in the speckled band?

In "The Adventure of the Speckled Band," key objects include the snake, which serves as the murder weapon, and the bell-pull, a seemingly innocuous feature that conceals the snake's entry point. The ventilator is also crucial, as it connects the victim's room to the killer's, allowing the snake to be delivered. Additionally, the gypsy's campfire and the whistle used by Sherlock Holmes play significant roles in the resolution of the mystery. These objects collectively contribute to the story's suspense and ultimate revelation of the crime.