Sentence:  It was the Lost <WSD>Oasis</WSD>, the <WSD>Oasis</WSD> of the vision in the sand. […] Deep-hidden in the hollow, beneath the cliffs, it lay; and round it the happy verdure spread for many a rood. […] Yes, the quest was ended, the Lost <WSD>Oasis</WSD> was the Found! 
Meaning of the word marked with <WSD> tags:  A spring of fresh water, surrounded by a fertile region of vegetation, in a desert.