This work is registered in the archives of the Calder Foundation, New York, under application number A07475.
The following remarks are personal recollections by the original owner: "In 1954 at my invitation from abroad Calder created this present mobile. In a bare, unfinished room, which was turned into a makeshift studio in a building under construction, equipped with basic tools, stands and benches, Calder managed to create the bustling scene similar to the atmosphere and clutter of his studio in Roxbury.
With the exception of his own favourite pair of special pliers brought with him, all of his tools (chisels, files, wrenches, etc.) were borrowed from or improvised for him by the craftsmen and builders on site. His materials were the same simple ones he had always used: steel wires, steel bars and aluminum sheets.
He worked on the bench with a medium sized vice mounted on it. At the
bench, Calder moved with quick almost jerky but sure motions, but
seemed never to make the wrong move, thinking out his designs
beforehand without sketches and working fast to create them.
While building this mobile Calder became the center of attraction and was accepted as a craftsman and friendly colleague by all metal workers, carpenters, plumbers and other fellow craftsmen working on the building site, who all found his work fascinating and quite mystifying."