Set the jars in a pan of water over a low burner.

Wash berries in a bowl of cold water to make sure they are free of grit and dust. Remove berries by hand and place them on a clean, dry towel to drain. Then remove the caps and crush the berries slightly with a clean, odorless, wooden pestle or a strong coffee mug.

Pour into a non-aluminum saucepan and set over a low flame to heat.

Meanwhile, heat the sugar either in a double boiler or in a dish in the oven, being careful not to brown it, but making sure it becomes very hot (about 10 minutes in a 350° oven). Now pour the hot sugar over the berries, turning the burner up while stirring the sugar around. The cooking should be as brisk as possible without scorching; it should take about 9 minutes in all.

As soon as the preserves begin to boil up, a scum will rise on the surface; skim it off right away with a wooden or silver spoon. It is much better to skim while it’s rapidly boiling, because that seems to cause the scum to remain in a mass and it’s easy to dip it out without getting too much of the syrup.

After 9 minutes of rapid cooking, pour the preserves into the hot jars, filling to about 1/8 inch from the top. Lift the jars out onto a dry surface to cool.

When cold, carefully melt paraffin and pour into the filled jars. When paraffin is cool, put on the lids and seal.