In Jack Finney's story "Contents of the Dead Man's Pocket," there is certainly an external conflict between the protagonist, Tom Benecke, and his surroundings, or "nature. This type of conflict is called external because it occurs between the character and an outside force; this particular kind of conflict is commonly known as man versus nature.
In "Contents of the Dead Man's Pocket," Tom struggles to make back into his apartment after finding himself in a very dangerous and precarious position on the ledge outside his window. When attempting to retrieve an important work document, Tom steps onto the ledge outside his window and follows the paper far enough to put himself in considerable peril.
When the yellow sheet containing Tom's assiduously collected data blows out the eleventh-story window, he climbs out to retrieve it and finds himself in danger on the ledge as he risks his life to regain it. When he does grasp the paper, Tom learns that he faces another challenge from his environment as the window from which he climbed has now slammed shut. He must risk death by punching the window's glass as hard as he can without losing his balance so that he can return to safety.