It started with haemorrhage, and some of the blood got into the lungs, and caused pneumonia.

He is better now, nearly well, in fact.

The prison doctor seemed a sensible man, and he spoke as if he were interested in Michael.
From what he said I gathered that he did not think Michael would survive another winter there.

The prison[1] stands in a sort of marsh.

It is a very good place to prevent prisoners escaping, but not a good place for them to keep alive in.