 The classical "reticello" pattern is a small uniform mesh of white threads in clear glass, with a tiny air bubble in every mesh rectangle.To make an object in this pattern, the glassblower first uses white single-thread "vetro a fili " canes to blow a cylindrical cup shape, twisting as he forms it so the canes are in a spiral, and using care not to totally smooth the inside ribbing that remains from the canes.Setting this cup aside (usually keeping it warm in a furnace, below its softening point), he then makes another closed cylinder in the same pattern, but twisted in the opposite direction, and retaining some of the ribbing on the cylinder’s outside.