"we will go back; your health is precious. You are rich, respected, admired, beloved; you are happy, as once I was. You are a man to be missed. For me it is no matter. We will go back; you will be ill, and I cannot be responsible.
The nitre! We will go back, Your cough.
You can't possibly be a mason!?
This is my sign
He kills Fortunato by walling him in.
By: Luke Maisel
When Montresor pulls out the trowl it foreshadows what's about to happen next. It's a very odd detail that hints to the reader that he is planning something which builds suspense in the story.