If you wear eyeglasses, seeing clearly is important. Since eyeglasses -- especially prescription eyeglasses -- can be expensive, it's critical to maintain their upkeep and clean them correctly. For example, using a dry tissue to clean lenses can leave small scratches on the glass from the harsh woven fibers in the tissue or from abrasive sediment already settled on the lenses. Never ever use glass cleaner or other harsh abrasives! However, there are other tricks you can use to successfully clean dirty eyeglasses.