Umberto Boccioni made a distinguished contribution to Futurist painting, then in 1912 he turned to sculpture, impatient with the way it was lagging behind modern developments. He formed a Futurist theory of sculpture, publishing the Technical Manifesto of Futurist Sculpture in 1912 and The Plastic Foundations of Futurist Sculpture and Painting in 1913. His aim was to make sculpture which would represent the dynamism of modern man, in motion in the modern world. 'Unique Forms of Continuity in Space' is the fourth of a series of striding figures, the other three now lost, in which Boccioni worked out his aim. The titles of the others are highly evocative: 'Synthesis of Human Dynamism', 'Spiral Expansion of Muscles in Movement', and 'Muscles in Speed.' Surviving photographs of them show how Boccioni worked out a series of variations of flowing forms which he developed to express movement. These forms were derived partly from the blurring effect seen in photographs of objects moving at speed. but mostly from the effects of overlapping and extended images seen in the chronophotographs of the pioneer photographer Etienne-Jules Marey, who used a single plate to record successive phases of a movement. Boccioni also wanted to express the way in which objects in motion interrelate with their surroundings as they pass, which he saw as an interpenetration of background elements cutting across the moving figure or vice versa. In his Technical Manifesto he wrote 'We ... proclaim the ABSOLUTE AND COMPLETE ABOLITION OF DEFINITE LINES AND CLOSED SCULPTURES, WE BREAK OPEN THE FIGURE AND ENCLOSE IT IN THE ENVIRONMENT.' 'Unique Forms of Continuity in Space' is the last of the series and, in the words of the art historian John Golding, '... blindingly simple and totally successful'. He also points out that by placing the figure on small blocks Boccioni forces on us 'an awareness of the full span of the figure's giant stride ... there is a sense of weightlessness and the sense of speed is now euphoric and heady ... The bulging muscles, half metal, half flame, are pulled back to reveal the trajectory of earlier phases of motion.' It has also been suggested, by the art historian Marianne Martin, that the figure can be associated with the vision of Marinetti (the founder of Futurism) of a mechanical superman 'built to withstand omnipresent speed. He will be endowed with unexpected organs adapted to the exigencies of continous shocks ...' One of these organs was 'a prow-like development of the projection of the breastbone which will increase in size as the future man becomes a better flyer'. This sounds very like the curved, cruciform projection jutting out from the head of 'Unique Forms of Continuity in Space'.
Simon Wilson, Tate Gallery: An Illustrated Companion, Tate Gallery, London, revised edition 1991, p.143