Put on the safety glasses and gloves. Apply a commercial polishing compound to the glass and polish it using a variable speed drill set on low. Most compounds contain cerium oxide as an abrasive. This removes glass until the surrounding area is level with the pit. As the glass is being removed, some of it will begin to fill the pit and give a false impression that the pit is being repaired. To prevent this, continually flush the area by lightly squeezing a sponge that has been soaked with water to keep the compound damp. [links]