Complex sentence: Sheltering in his house, the narrator sees a fleeing artilleryman moving through his garden, who later tells the narrator of his experiences and mentions that another cylinder has landed between Woking and Leatherhead, cutting off the narrator from his wife.
Split into simpler sentences: Sheltering in his house, the narrator sees a fleeing artilleryman moving through his garden. The artilleryman tells the narrator of his experiences and mentions that another cylinder has landed between Woking and Leatherhead, cutting off the narrator from his wife.