Window Pain

It was 3.00am in the morning when we were awoken by an almighty thud followed by a brief bong. That was three weeks ago. Three hours later we prepared to journey to London for three days without having detected the source of the eerie, resonant sound. Upon our return we noticed that the central panel of nine identical stained glass panels had cracked from corner to corner with minor fractures all over it. The damage was all on the inside, as if a giant bat had flown into the window at great speed. When inspected, the glaziers were baffled as to what caused it. The packing was intact, and, moreover, this is "Grade A" glass. They removed the panel and filled the hole with chipboard until the art company that customise stained glass have made another identical panel.