The young lady had just retired to her room when sounds of a struggle ensue, and cries of "Murder!" and revolver shots ring out. When her locked door is finally broken down by her father and a servant, they find the woman on the floor, badly hurt and bleeding. No one else is in the room. There is no other exit except through a barred window. How did the attacker escape?

The young lady had just retired to her room when sounds of a struggle ensue, and cries of "Murder!" and revolver shots ring out. When her locked door is finally broken down by her father and a servant, they find the woman on the floor, badly hurt and bleeding. No one else is in the room. There is no other exit except through a barred window. How did the attacker escape?