"I now replaced the nail and regarded it attentively. A person passing out through this window might have reclosed it, and the spring would have caught—but the nail could not have been replaced. The conclusion was plain, and again narrowed in the field of my investigations. The assassins must have escaped through the other window. Supposing, then, the springs upon each sash to be the same, as was probable, there must be found a difference between the nails, or at least between the modes of their fixture. Getting upon the sacking of the bedstead, I looked over the headboard minutely at the second casement. Passing my hand down behind the board, I readily discovered and pressed the spring, which was, as I had supposed, identical in character with its neighbor. I now looked at the nail. It wa
