an American tinsmith and the patentee of the metal screw-on lid for fruit jars that have come to be known as Mason jars. He also invented the first screw top salt shaker in 1858. Mason invented a square-shouldered jar with threaded screw-top, matching lid, and rubber ring for an airtight seal – the Mason jar. Until the 1830s, long before refrigeration and hothouse gardens, many fruits and vegetables had been available only seasonally, but the recent development of jars had made canning a practical alternative to drying, pickling, or smoking to preserve food.
