Grape Juice Sauce

This is a foamy dessert sauce built on unbeaten-then-beaten raw egg white, and the printed text has run three separate sauce recipes together. Both facts matter before anything else.

• The raw egg white is never cookedThe whites are beaten with sugar and fruit juice and served immediately, with no heat at any stage and no acid strong enough or long enough in contact to matter. Raw shell eggs can carry Salmonella in the white as well as the yolk, and a sauce like this is typically served to whoever is at the table, children and elderly guests included. A current recipe using pasteurised egg white or a cooked meringue method should be used instead.
• The page is three recipes, not oneAfter "serve at once" the text jumps to a creamed butter-and-sugar hard sauce (1/3 cup butter, 1 cup powdered sugar, flavouring), then breaks off mid-way into a third with 3 egg whites and 1 cup powdered sugar and no method at all. Nothing is missing from the grape juice sauce itself, but the lines below it do not belong to it.
• Powdered sugarIn American books of this period "powdered sugar" generally means a finely ground sugar, close to what is now sold as confectioners' or icing sugar, though usage varied from book to book. The 7/8 cup reads as a deliberate measure rather than a misprint.
• Grape juiceThe juice intended is most likely the sweet unfermented bottled grape juice, commonly Concord, that became widely available around the turn of the century, rather than a wine or a reduced syrup. It is dark, quite sweet and strongly perfumed.
• Serving intentA foamy sauce of this kind would have been spooned over steamed puddings, cottage pudding or plain cake. Foams of this sort collapse within minutes, which most likely accounts for "serve at once".