I clearly remember one of my high school English assignments. We were asked to pick a song we liked and find a poem to compare it to. (I think it was like that actually. I think the assumption was that we knew and liked a great many songs and that we would have to go out and find a poem. In my case, I don't think that assumption was too far off.) I chose Duke Ellington's "The Blues" from Black, Brown and Beige and Longfellow's "The Rainy Day". We had to make a poster, and I drew a picture of a film noir detective (to illustrate jazz, I guess) standing by a "mouldering wall" in the rain. I remember my teacher remarking on the wall.
There were some really obvious similarities, which made the assignment easy. "The Blues" opens with the line "The blues ain't nothing but a cold grey day"; Longfellow's poem begins "The day is cold, and dark, and dreary." They provided an obvious way of comparing the blues to romantic melancholy. But there is also an important difference. The romantic poet accepts his melancholy, while the blues singer renounces it. Longfellow says
Be still, sad heart! and cease repining;
Behind the clouds is the sun still shining;
Thy fate is the common fate of all,
Into each life some rain must fall,
Some days must be dark and dreary.
The victim of "The Blues" takes it altogether more personally:
'Tain't nothin' I want to call my own
'Tain't sump'n' with sense enough to get up and go.
'Tain't nothin' like nothin' I know.
If I were to do the assignment today, I think this is what I would focus on. Should we dwell upon our melancholy, knowing that it is "the common fate of all" and that it inevitably passes? Or should we see it, while it befalls us, simply as a "one-way ticket from your love to nowhere"? Ellington tells us the blues "ain't nothing but a dark cloud marking time". Longfellow says, "Behind the clouds is the sun still shining". What image is the more precise presentation of the emotion?