Duchampian Sliding Screens Salesman Sample (or Moire Pattern Making Machine) early printing block but these are the first

but these are the first that I've found

7 1/4" x 5 1/4"

10 1/4" x 8"

and I believe yellow wax crayon on white watercolor paper

Duchampian Sliding Screens Salesman Sample (or Moire Pattern Making Machine) early printing block but these are the firstAnother example of a thing made for one purpose, but which, recontextualized, feels quite like an artwork, this one feeling very Duchampian to me, including for his ongoing interest in thresholds and portals (doors, windows, peepholes, glass, etc..) I believe it was made as a salesman sample for sliding screens, here with three screens, each with handles for sliding them in one direction or the other. They can all be slid, one by one, to one side or