A Painted Sketch

I've been working in gouache and casein on small panel and paper with the intention of redressing my interest in the water medium I once used as an illustrator.  I now find I also have to take another look at  "the sketch" just what is a sketch?  Issues of size, intent, medium, and function are the most common determinants used  to separate one type of artistic endeavor from another.

In the eighteenth century, France had a scale of preliminary works that  progress from croquis, to pochade, to etude. and the categories did not stop there. "The Painted Sketch"an anticipation or maybe a taste.