Collaboration with Evaporation

water glass, ink and watercolor residue, 3”x3”x4”, ongoing
The same water glass is used to rinse my brush when doing ink drawings (a common form of sketching for me). A ring of color graphs the amount of time that passes (the amount of water that evaporates) since the last time I made ink drawings. The glass is complete when I see that all of the water has evaporated since the last time I used it.
There are currently three completed glasses.