The statement: The line "I scarcely grieve, O Nature!" is an example of apostrophe," is true.
In literature, apostrophe refers to a figure of speech, and an arragement of words which sometimes expresses exclamations, such as “Oh.” When a writer or speaker implements an apostrophe, he/she is speaking directly to someone who is not present or is dead, or is addressing to an inanimate object or an abstract idea.