John Mason's 1858 Patent for the Mason Jar Lid

An 1858 invention by John L. Mason that introduced a threaded glass jar and a screw-on metal lid to create an airtight seal for home food preservation.

What it covers

The patent describes a method for sealing glass jars using a threaded neck and a corresponding metal screw cap. By incorporating a rubber gasket between the glass rim and the metal lid, the design creates a vacuum seal when the jar cools after being filled with hot contents. This mechanism effectively prevented air from entering the jar, which was essential for long-term food storage before the widespread availability of refrigeration.

What it doesn't cover

• —Does not cover non-threaded glass containers or those using cork stoppers.
• —Does not cover the process of heat-treating or canning food itself.
• —Does not cover plastic lids or modern vacuum-sealing machines.

The clever bit

The innovation was the use of a threaded glass neck that allowed a metal cap to be tightened down directly onto a gasket, creating a reliable, reusable airtight seal that was simple enough for home use.

Why it matters

This invention revolutionized domestic life by allowing families to safely store seasonal harvests for year-round consumption. It became a staple of American kitchens and remains a cultural icon of home preservation today.

Real-world examples

• 1.Classic Ball Mason jars
• 2.Home canning supplies
• 3.Vintage glass food storage containers