Sentence:  Their reign has never ceased, but only waned in power a little, for the <WSD>Sidhe</WSD> still pass in every wind, and dance and play at hurley, and fight their sudden battles in every hollow and on every hill; but they cannot build their temples again till there have been martyrdoms and victories, and perhaps even that long-foretold battle in the Valley of the Black Pig. 
Meaning of the word marked with <WSD> tags:  "Alternative capitalization of sidhe."