Sentence:  The evergreen! How beautiful, how welcome, how wonderful the evergreen! ... You will think me <WSD>rhapsodising</WSD>; but when I am out of doors, especially when I am sitting out of doors, I am very apt to get into this sort of wondering strain. 
Meaning of the word marked with <WSD> tags:  To speak with exaggerated or rapturous enthusiasm ("about, (up)on" or "over" something).