Berwick Sponge Cake

From 1922:

The following recipe is from a collection of recipes in the possession of an elderly woman who has lived her life in Berwick, Mo. She says this recipe is reliable, or to quote her: “It never fails if directions are followed.”

Beat three egg whites and yolks together, two minutes. Add one and one-half cups of sugar. Beat five minutes.
Mix two level teaspoons of cream tartar with one cup of flour. Beat into cake two minutes.
Dissolve one level teaspoon of soda in one-half cup of cold water. Add to cake mixture and beat one minute.
Finally add another cup of flour mixed with one-half teaspoon of salt and beat one minute.
Then add the juice and grated rind of half a lemon. Bake 30 minutes in moderately hot oven.