Third in a series about the national pavilions at the Venice Biennale.

Some artworks call up tears by jerking you around until your eyes can't help but water up. They're sentimental and manipulative, like melodrama, and relatively common. Others, much rarer, get you crying by honestly displaying how tragic a place the world can be. A piece by Juan Manuel Echavarria, one of several talented Colombians representing their nation in the Venice Biennale of contemporary art, which opened here Sunday, brought a lump to my throat. I didn't feel as though some operatic artist had put it there.

Echavarria's piece is called "Bocas de Ceniza" -- "Mouths of Ashes," apparently the name of the estuary of the Magdalena River where corpses of the victims of 40 years of civil war tend to wash up. It consists of seven color videos shown one after the other, lasting about 15 minutes overall.

Each video gives a static close-up of the face of a Colombian peasant, shown against a simple white background. All seven sitters -- six men and a woman, mostly of African descent, one apparently a blind albino -- then sing a song about the sorrows in their lives, written by themselves. (English subtitles run below.) There's just a face, a voice, a simple tune and some heartbreaking lyrics.

One man, shaking with emotion, sings about the horrors he and his brother faced when fighters accused them of treachery. The brother, his face half-smashed -- one eye seems blind -- sings about the time he survived a massacre.

A handsome black teenager sings about the day fighters set fire to a church sheltering fellow villagers. As he ends, tears start pooling in his eyes. I dare viewers to keep tears out of theirs.

Domingo Mena is one of the singing subjects of Colombian artist Juan Manuel Echavarria's moving series of seven short videos.