Grape Lemonade

A punch-bowl cooler that leans on bottled grape juice and a trace of peppermint oil. The proportions are sound, but two details in the original need pinning down before you start.

• The peppermint is the hingeFive drops of oil of peppermint is a genuine dose, not a flourish — the oil is many times stronger than the alcohol-based extract sold as "peppermint flavoring." Use a food-grade essential oil and count the drops; if all you have is extract, start at half a teaspoon and taste.
• Dissolve the oil in the syrup firstThe instruction to add the mint to the syrup is presumably meant to distribute the oil, which will not dissolve in water or juice; stirred straight into cold liquid it beads on the surface and one glass gets the whole dose.
• Syrup is unmeasuredNo quantity is given. Simple syrup is equal parts sugar and water by volume, boiled to clear; start with half a cup for the batch and add by the tablespoon. Grape juice is already sweet, so this drink needs less than a lemonade would.
• Limes, despite the nameThe title says lemonade but the ingredient is lime. Four limes yield roughly half a cup of juice. Lemons will work and give a rounder, less resinous result, but the lime is what balances the grape.
• Grape juiceUnsweetened bottled juice, most likely Concord, is the plausible intention here — purple, musky, and quite sweet on its own. Sweetened grape drink or cocktail will make the finished pitcher cloying.
• Carbonated water and volumeThree cups juice plus four cups seltzer plus syrup and lime lands near two quarts, so the ice is meant to chill rather than dilute. Add the seltzer last and stir once, not vigorously, to keep the fizz.
• YieldTwo quarts poured over ice gives six generous glasses, or eight punch cups. It does not keep well, as the carbonation fades quickly.