John Landis Mason

Before the development of refrigeration and hothouse gardens, many fruits and vegetables were available only seasonally. From the 1830s, the development of glass jars made canning a practical alternative to drying, pickling, or smoking to preserve food. Unfortunately, the mouth of the jar was unthreaded, across which a round, flat tin lid was laid and sealed with wax. The canning procedure was messy, unreliable, and unsafe – if the wax was not applied properly, it allowed bacteria to thrive in the jar. Mason's innovation was a square-shouldered jar with threaded screw-top, matching lid, and rubber ring for an airtight seal. Mason's easy-to-use, re-usable jars made home canning popular among American settlers, homesteaders, and even in urban homes. Most Mason jars were manufactured by competitors after his patent expired in 1879. ==Personal life==

He was married and had eight children, six surviving to adulthood. He died in poverty in a tenement house in New York City in 1902. ==Patents==

United States patent 22,186, dated November 30, 1858, is primarily on the use of exterior threads in the jar and a corresponding metal cap. Later patents such as Nr.102,913 improved upon this in various ways such as the addition of rubber rings. • . • . In the case of the United States Supreme Court, 94 U.S. 92 (1876), CONSOLIDATED FRUIT-JAR COMPANY v. WRIGHT, the Court ruled that Mason's patent had been abandoned to the public. == References ==