Many of Ernst's works can be found in a special exhibit at the Smithsonian's National Gallery in DC. I visited the exhibit yesterday with my wife and parents. One of the pieces, energetically entitled The Gramineous Bicycle Garnished with Bells the Dappled Fire Damps and the Echinoderms Bending the Spine to Look for Caresses, is pictured below:
Dada sought to recast the rules of art, or to break them entirely -- in doing so, the movement revealed its artists' perception of the giddy unreality and inhumanity of the First World War and its aftermath. The obviously incomplete clockworks of Francis Picabia remind me of proto-Rube Golberg Machines, and The Gramineous Bicycle, above, puts me in mind of Ernst Haeckel's Kunstformen der Natur and its astounding drawings of microscopic organisms, here recast as cogs in what is merely a machine.
If you're in the DC area, visit this exhibit! You have until May 14.