A shattered ceiling light bulb,Grahame ?

I don't expect for a minute, that the farmhouse had been scrutinised to the extent that the police would have been looking for bullet holes anywhere within the place,,as they wouldn't have taken into consideration the single shot that had been fired earlier in the evening.
It would have appeared that the shotgun hadn't formed part of the case,,,but in my estimation,because it would have been easier for Sheila to have handled,,it has one of the most important issues in this case.