Around the mid-1930s Calder developed what has become the classic form of the mobile: an elegantly balanced network of wires and painted pieces of sheet metal, suspended from the ceiling. Rather than following a series of predetermined movements, these mobiles are continually changing. In a text from 1932, Calder envisaged works with ‘each element able to move, to stir, to oscillate, to come and go in its relationships with other elements in its universe’. This delicate series of interrelations means that the work as a whole seems to sway with its own independent life.

In 1933 Calder moved to an old farm at Roxbury, Connecticut. As his sculptures seemed to become less geometric and more organic in form, critics would draw parallels with the natural world. Titles such as Vertical Foliage and Snow Flurry I reinforce the connections with the spreading growth of the tendrils of plants, or with Calder’s impressions of a blizzard.

The floor-based works in this room show that Calder continued to experiment with the ways in which his sculptures occupy space, using slender wires to outline volumes. There are still echoes of his fascination with popular entertainment, from Tightrope (along which abstracted wire symbols are balanced like circus performers) to the carousel-like form of Untitled 1937.