Describe jem ,scout, and dill do in the radley yard at the beginning of the chapter. what do they see that makes them run away ?

They sneak into the Radley's back yard with the goal of peeping in one of the windows to get a look at Boo. Scout and Jem hold up Dill to a window so that he can get a lookin the window, but all he had seen were curtains and "a little teeny light way off somewhere". They move onto the back of the porch, where Jem tip toes up to look into another window. They suddenly saw a shadow of a man, which frighten the children so they ran as fast as they could out of the yard.