The Case of a Well and Things that May Fall in It (Fatwa best explains Ahadith 2-12 as well as the following chapter.)

5. Ahmad ibn Idris has narrated from Muhammad ibn Salim from Ahmad ibn al-Nadr from ‘Amr ibn Shimr from Jabir who has said the following: “This is about the case of al-Sam al-Abras (a poisonous snake) that falls in the well. Abu Ja‘far عليه السلام, has said, ‘It is not harmful. Just stir the water with the bucket.’”