After Longfellow died his brother, Samuel Longfellow, wrote a book about him and included the below poem. It was actually written in 1842, when Longfellow was 35 years old but it was only published in 1886. The title, “Mezzo Cammin,” is Italian for the middle of life. The words come from the opening line of Dante’s Divine Comedy.

Mezzo Cammin

Half of my life is gone, and I have let

The years slip from me and have not fulfilled

The aspiration of my youth, to build

Some tower of song with lofty parapet.

Not indolence, nor pleasure, nor the fret

Of restless passions that would not be stilled,

But sorrow, and a care that almost killed,

Kept me from what I might accomplish yet;

Though, half-way up the hill, I see the Past

Lying beneath me with its sounds and sights,—

A city in the twilight dim and vast,

With smoking roofs, soft bells, and gleaming lights,—

And hear above me on the autumnal blast

The cataract of Death far thundering from the heights.

*~*~*~*~*

I found this poem in an article in the Oxford Research Encyclopedia article on Longfellow, by Susan Balee and Dana Gioia. https://doi.org/10.1093/acrefore/9780190201098.013.714

One of the vivid images in The Divine Comedy comes when Dante and Beatrice are traveling high up in heaven and they look down and see the earth below. Longfellow called the earth a “threshing floor” in his translation and it is a rich symbol. “Mezzo Cammin” also evokes that moment of looking down and backwards into the Past.

Paradiso Canto 27: lines 79-90 (I think)

Whereat the Lady, who beheld me freed
    From gazing upward, said to me: “Cast down
    Thy sight, and see how far thou art turned round.”

Since the first time that I had downward looked,
    I saw that I had moved through the whole arc
    Which the first climate makes from midst to end;

So that I saw the mad track of Ulysses
    Past Gades, and this side, well nigh the shore
    Whereon became Europa a sweet burden.

And of this threshing-floor the site to me
    Were more unveiled, but the sun was proceeding
    Under my feet, a sign and more removed.