Your son is badly hurt. But he is not in any pain.
Use of nature and weather (setting)
This uses pausing to add tension because the woman at first thinks her son is alive and injured but after a few seconds she and the reader understand that he is dead
"Without, the night was cold and wet, but in the small parlour of Laburnam Villa the blinds were drawn and the fire burned brightly" this helps because it adds tension to the setting of the villa and makes it more spooky.