Remove the strings from the beans, and, if nice and young, they can be left whole. Wash them, then cook in boiling water for five minutes. Remove from the boiling water and plunge at once into cold water, then drain, and arrange neatly in jars. Fill up the jar with slightly salted water, using one teaspoon salt to every pint of water; adjust the rubbers and screw down lids loosely, or, in the case of spring-top jars, adjust the clamp but do not fasten down. Pack the jars in the boiler or saucepan as directed in "General Rules For Canning Vegetables," and sterilise again for one hour. Repeat the process the third day, screw down the lids tightly, or fasten down the clamps of spring-top jars, and put away in a dry, cool place.
This three-day method is the most reliable process for canning beans, although success may also be attained by sterilising them for two hours on two successive days instead of one hour for three days.