What is the subject of a participial phrase?

But the hand which I now saw, clearly enough, in the yellow light of a mid-London morning, lying half shut on the bedclothes, was lean, corded, knuckly, of a dusky pallor and thickly shaded with a swart growth of hair.

This is from the classic novel Strange Case of Dr. Jekyll and Mr. Hyde. I wonder what was lying half shut on the bedclothes. Was it a hand or speaker itself?

It was the hand.

There is technically some ambiguity, but we do not talk of people lying half shut, or for that matter parts of the day - a mid-London morning might just as well have been modified by lying half shut.