I learned something new from browsing through 1921 magazines. Did you know that string beans could be canned using a pressure cooker that long ago? I didn’t until I saw this photo and the accompanying article. Here’s what it said.
String Beans Canned in Pressure Cooker
Wash beans thoroughly, cut ends, and remove strings and cut as for the table. Dip in boiling water for two minutes, using a wire basket. Fill into cans, heat, and add boiling water and one teaspoonful of salt to each quart can of beans. Put on rubber ring and glass top. (Do not secure the top tight until after the cooking is done and the jar removed to cool.) Place on rack in pressure cooker, put on cover and process fifty minutes at 235 deg., eight pounds pressure.
American Cookery (August – September, 1921)