I had to sit and mind the gift shop at our local art league (http://www.capecoralartleague.org/ )and to pass the time I decided to try the brushes I bought several years ago that have water in the handle of the brush by Aquaflow. I thought they might be handy for painting in confined places where you might not want to have a cup of water. It was frustrating in the beginning because I'm so used to rinsing my brush frequently in water; with this brush you have to squeeze it to flush whatever pigment you are using out of it before going on to another. It's nessesary to have something absorbent handy to catch the drips and to wipe the brush; papertowel or sponge work well. I painted on a postcard sized piece of w/c paper trying to keep in mind a confined space. It's no masterpiece but it gave me some insight into painting with these interesting brushes. The Aquaflows have a valve in them that keep the pigment from being sucked into the water in the handle which was a problem with another brush that I had. I'm thinking that I might even be able to do quick sketches while riding in the car on long trips.
