Definition of "mournfully"

"Why have not we an immortal soul?" asked the little mermaid mournfully; "I would give gladly all the hundreds of years that I have to live, to be a human being only for one day, and to have the hope of knowing the happiness of that glorious world above the stars."

1836, Hans Christian Andersen (translated into English by Mrs. H. B. Paull in 1872), The Little Mermaid

The steamer itself had vanished, but the great scroll of smoke still hung in the air and drooped like a flag mournfully in valediction.

1927 May, Virginia Woolf, To the Lighthouse (Uniform Edition of the Works of Virginia Woolf), new edition, London: Leonard and Virginia Woolf at the Hogarth Press, […], published 1930, part I (The Window), page 140

So she dared not tell anyone how she felt, but went about mournfully, with a heavy heart.

1956 , Johanna Spyri, Heidi, translation of original by Eileen Hall, page 104