When I started doing the 'Bursts' [paintings Gottlieb started c. 1958] I began to do part of the painting horizontally. It was necessary to do that because I was working with a type of paint which had a particular viscosity, which flowed, and if it were on a vertical surface it would just run. If it were on a horizontal surface, I could control it... I was using a combination of brushes and knives, palette knives... and spatulas... I've tried everything, rollers, rags, I've put paint on with everything.