The work is preceded by a sketch in which some figures of unskilled workers distributed on the proscenium, anonymous dark masses bent on heavy wheelbarrows, give life to a further homage to the epic of workers in accordance with the theme of The Fourth Estate. Over time the bridge undergoes a radical metamorphosis whereby the eloquent social message is replaced by a more subtle symbolic content. A canvas of considerable size, the composition is centered on the solid linear structure of the bridge and on the curvature of them that intersects it in the center formed by the bed of the stream, on the ground, and by the trajectory of the cloud, in the sky, located in the median plane to the right, the three silhouettes against the light of a man prone on the water to quench his thirst and of a woman with a child in her arms, a little further on a shepherd who goes away with the small flock just visible in the half-light. All around, nothingness: only the silent peace of the evening that falls slowly and inevitably. After the unenthusiastic reception of the painting at the 1905 Venice Biennale, Pellizza undertook a real general revision, defining, among other elements, a more prominent profile of the mountain range in the background, a tribute to the themes and ways of Giovanni Segantini.