Lemon Ice

A plain water ice built on a boiled sugar syrup, the standard American formula of the period. The only step the original leaves out is the freezing itself, which it hands off to a separate set of directions.

• The hinge: chill before you freezeThe syrup must be cold, ideally refrigerator-cold, before it goes into the machine. Pouring a barely cool base into a churn melts the surrounding ice, the mixture freezes coarsely, and you get grit instead of a smooth ice.
• Why the lemon goes in off the heatBoiling the water and sugar for five minutes dissolves the sugar fully and drives off a little water, concentrating the syrup. The juice is added after, since cooking it flattens the fresh, sharp aroma that is the whole point of the dish.
• Freezing without a churn"See directions for freezing" would have pointed to a hand-crank freezer packed with cracked ice and rock salt; period books commonly give something in the region of three parts ice to one of salt. A modern ice cream maker does the same job; failing that, freeze in a shallow metal pan and break up the crystals with a fork every 30 minutes until firm, about 3 to 4 hours.
• How many lemonsThree-quarters of a cup of juice takes roughly four to six lemons depending on size. Strain out pulp and seeds as directed, then strain again after chilling if any settles.
• Sugar is structure, not just sweetnessTwo cups of sugar to four of water is a generous but fairly standard proportion for a water ice; sugar depresses the freezing point and keeps the ice scoopable. Cutting it back gives a harder, more icy block that has to sit out before serving.
• Yield and servingRoughly 5 to 6 cups of base, which freezes to about 6 to 8 servings. Water ices of this type were served in glasses or cups, sometimes between courses as well as at the end of a meal.