conclude who was the murderer who died or who look straight over mrs salmon?

His name was Adams.

"So she went to the window and saw Adams(that was his name) on the steps of Mrs Parker's house. He had just come out and he was

wearing gloves. He had a hammer in his hand and she saw him drop it into the laurel bushes by the front gate. But before he moved away, he had looked up - at her window."