He was, in fact, on the point of regretfully abandoning his efforts on the supposition that she had retreated to her own room when her voice rang suddenly down the back stairs.

She was calling agitatedly for help.
It was enough for Bertie.

He tore up the stairs with lightning speed, boldly announcing his advent as he went.
He found her at the top of the house in an old cupboard used for storing fruit.

She was mounted upon a crazy pair of steps that gave signs of imminent collapse, and to save herself from the catastrophe that this would involve she was clinging to the highest shelf with both hands.
"Be quick!" she cried to him.

"Be quick! I'm slipping every second!" The words were hardly uttered before the steps gave a sudden loud crack and fell from beneath her with a crash.