Sentence:  Forty years ago an English writer , W. L. George , dealt with this subject in Eddies of the Day , and said , as an example , that ' Saint George for Merry England ' would not start a <WSD>spirit</WSD> half so quickly as ' Strike frog eating Frenchmen dead '' ' ! 
Meaning of the word marked with <WSD> tags:  any incorporeal supernatural being that can become visible (or audible) to human beings