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Blackberry Jam
2 pounds sugar Wash and pick over blackberries, heat, then press through a sieve. To this purée add sugar and boil one half hour. Pour into glasses and cover.
Black, Red, and White Currant Jam 4 pounds currants 4 pounds sugar Stem currants, crush slightly; add sugar, let stand over night; in the morning cook slowly one half hour, stirring often. Turn into glasses and cover.
Green or Ripe Grape Jam Wash and stem grapes. Separate skins from pulp.
Cook skins until tender, press through a sieve. Cook pulps ten minutes, press through a sieve. Combine purées; add one pound of sugar to every quart of purée; boil one half hour, stirring often. Pour into glasses and cover. Raspberry or Strawberry Jam 4 pounds raspberries or strawberries 2½ pounds sugar 21 pounds sugar Mash berries; add sugar; cook thirty minutes, stirring very often. Pour into glasses and cover. 4 pounds currants
A cluster of four jams set down in the telegraphic style of a 1900s preserving chapter, with the fruit weight for the blackberries lost somewhere in the typesetting. The proportions and the sealing method are where modern practice diverges.
- The missing and doubled quantitiesThe blackberry entry lists only "2 pounds sugar" — the fruit weight has dropped out, and the surrounding recipes suggest it was 4 pounds of berries. The raspberry/strawberry entry prints both "2½ pounds sugar" and "21 pounds sugar"; the latter is plainly a misprint and 2½ pounds is the intended figure. The stray "4 pounds currants" at the end belongs to the currant recipe above.
- Sugar ratioThe berry jams run leaner than the classic pound-for-pound jam: roughly 5 parts fruit to 3 parts sugar in the raspberry/strawberry entry, and 1 pound sugar per quart of grape puree. The currant jam, by contrast, is pound-for-pound. Less sugar means a softer set and a shorter shelf life, and the half-hour boil concentrates the mixture by evaporation.
- Judge the set, not the clock"Boil one half hour" reflects the wide, shallow preserving pans usual in this period. In a modern heavy pot, cook to 220F on a candy thermometer, or until a spoonful chilled on a cold saucer wrinkles when pushed. Thirty minutes at a hard boil in a narrow pan will overcook berry jam to a dark, caramel-tinged paste.
- "Glasses" and coveringThese are jelly tumblers, commonly covered in period practice with a disc of melted paraffin. Paraffin sealing is no longer recommended — the wax shrinks and cracks and lets in mould. Ladle into hot canning jars, leave a quarter-inch headspace, fit two-piece lids and process in a boiling water bath for ten minutes, or refrigerate and use within a month.
- Why the currants sit overnightStanding with sugar draws juice out by osmosis, so the fruit needs less added liquid and less boiling. Currants are also among the highest-pectin fruits in the garden, which is why they need no help to set; strawberries are much lower and blackberries vary with ripeness, so both tend to give a looser jam.
- The grape methodThis is written for slip-skin American grapes — Concord and its kin — where the pulp pops free of the skin. The two purées are cooked separately because the skins need long cooking to soften while the pulp only needs enough heat to release the seeds. Seedless table grapes do not behave this way and need no separation.
- SievingBlackberry and grape purées are pressed to remove seeds. A food mill with the fine plate does in two minutes what a wooden pestle and hair sieve did in twenty; a chinois and ladle work as well.
- YieldFour pounds of fruit with sugar gives roughly six to eight half-pint jars, depending on how far the boil is carried.
Lowney's Cook Book was compiled by Maria Willett Howard and issued by the Walter M. Lowney Company, the Boston chocolate manufacturer — one of the many general cookbooks a food business put out in the early 1900s partly to sell its own product, though the preserving chapter has nothing to do with cocoa. What dates these recipes most precisely is what they lack: commercial powdered and liquid pectin did not reach American kitchens until the following decade, so a cook setting jam in 1907 relied entirely on the fruit's own pectin, on long boiling to concentrate it, and on the acid and sugar already present. That is why currants and grapes are handled confidently while berry jams are simply boiled hard and hoped for. The jelly tumbler sealed with paraffin, universal here, remained standard household practice for a long time afterward, before extension services began advising against it.