This section is from the book "Save It For Winter.", by Frederick Fry Rockwell. Also available from Amazon: Save It For Winter; Modern Methods Of Canning, Dehydrating, Preserving And Storing Vegetables And Fruit For Winter Use, With Comments On The Best ... For Saving, And When And How To Grow Them.
Prepare the berries as for canning. Place two quarts in a wide-bottomed preserving kettle and cover them with one and a half quarts of sugar. Place the kettle over a slow fire. Do not stir the berries, but shake the kettle frequently as if popping corn. Gradually the sugar dissolves and the liquid covers the berries, when this point is reached, increase the heat enough to cause boiling, and continue the boiling slowly for fifteen minutes. Place a new rubber on a jar, fill it to overflowing with berries and syrup, and seal it at once. Proceed likewise with other jars until all the fruit is sealed.
Caution: Strawberries heated thus scorch very easily, so the fire must be carefully watched. Strawberries cannot be preserved successfully by this method if a small-bottomed kettle is used. After the boiling-point is reached, avoid hard boiling; allow the berries to simmer.
Prepare the berries and a heavy syrup as for canning, while the syrup is boiling rapidly, drop in large, firm berries until the syrup is thick with them but not crowded. Lower the heat somewhat and continue the boiling for fifteen minutes, or until the berries are a rich red color and the syrup is thick. Place a new rubber on a jar, fill it to overflowing with the berries and syrup, and seal it at once. Proceed likewise with other jars until the preserves are all sealed.
Caution: Do not cook more than two quarts of berries in the kettle at one time.
Marmalade affords the best means of utilizing small and overripe berries free from decay, wash the berries carefully and quickly, stem them, place them in a preserving kettle, crush them, and add three-fourths as much sugar as there is crushed fruit. Boil the marmalade over a slow fire for twenty minutes, stirring it often enough to prevent scorching. Seal it in jars.