"All things move, all things run, all things are rapidly changing," wrote the Futurists, one of them Balla, in 1910. Elaborating on Cubism's experiment in fracturing forms into planes, the Futurists further tried to make painting answer to movement: while the Cubists were concentrating on still lifes and portraits—in other words, were examining stationary bodies—the Futurists were looking at speed. They said: "The gesture which we would reproduce on canvas shall no longer be a fixed moment in universal dynamism. It shall simply be the dynamic sensation itself."
The backdrop to this painting is fixed architecture—a window, a drainpipe, a balcony—but the arcs that snake across the foreground are pure rush. The shapes of the swifts (are there four or forty of them?) repeat in stuttering bands, but their substance seems to evaporate: melting into light, the birds are lost in the paths of their own swooping soar. "Dynamic sensation," in Balla's time, was newly susceptible to scientific and visual analysis. Balla knew the photography of Étienne-Jules Marey, which described the movements of animals—including birds—through closely spaced sequences of images; Swifts emulates Marey's scientific visual analysis, which, in Balla's time, subjected "dynamic sensation to scrutiny," but adds to it a sense of exhilarated pleasure.