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Blackberry Preserve
The berries are prepared in the same manner as plums, excepting that water is not added, the berries being usually very juicy. Use glass jars in preference to stone ones.
This entry is a cross-reference rather than a standalone recipe: it tells you to follow the book's plum preserve method minus the water, and gives no weights, no sugar ratio, no boiling time and no sealing instructions. That absence is the problem.
- No sugar ratioNo sugar ratio given here -- A preserve keeps because sugar concentration and acidity make the syrup inhospitable to spoilage organisms. This entry states no fruit-to-sugar proportion of its own; whatever ratio applies would have to come from the book's plum method, which is not reproduced on this page.
- No processing stepModern practice for any sealed fruit preserve is a measured boiling-water bath, timed and adjusted for altitude. This entry says nothing about processing or sealing; whether the plum method it points to describes anything more than filling and closing the jar cannot be judged from this page.
- No cooking time or set pointNo cooking time or set point on this page -- Nothing in these two sentences tells you how long to boil the blackberries or how to judge doneness; any such guidance would be in the plum entry being referred to. Undercooked preserve stays thin and dilute and the sugar never concentrates enough to do its work.
- The jar advice is period-specific"Glass jars in preference to stone ones" most likely means glazed earthenware or stoneware crocks, which could not be sealed reliably and which, depending on the glaze, could carry lead. The book gives no reason itself. The instruction is sound as far as it goes, but a modern two-piece canning lid on a tested Mason jar is a different thing entirely from a period glass jar with a rubber ring.
- Why no water is addedThe one genuinely useful line in the entry: blackberries release a great deal of juice on heating, so the water needed to start plums would only thin the syrup. That observation is still correct.
- What to do insteadUse a current, tested blackberry preserve or jam recipe with stated weights and a processing time. Read this entry as a document of how preserving was described before those standards existed.
Blackberries in nineteenth- and early twentieth-century American household books were often gathered wild, though cultivated varieties were also widely available by this date; the terseness here is better explained by the book's own structure. The Butterick Cook Book (1911), published by the pattern company as part of its broad line of domestic manuals, organises its preserving chapter around a few master methods, and individual fruits are then handled as brief variations on them, which is why blackberries get two sentences. The preference for glass over stone reflects a real transition of the period: glazed earthenware crocks, long a default for putting food by, were giving way to screw-top and clamp-top glass jars that let the cook see the contents and seal them more reliably. Safe home canning as we understand it, with tested ratios and timed water baths, was still being worked out by agricultural extension services in the decades that followed.