What is the scientific inquiry used to investigate a natural pneumonia known as?

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.

the most likely explanation for this is that his wounds have started to scab over and that stops the bleeding.