From 1914:

Cream ½ cup of butter with ½ cup of brown sugar, add pinch of salt, ¼ teaspoon of ginger. Sift 2 ½ cups of flour.
Put 2 even teaspoons of soda into 1 cup of boiling water. Add one third of the hot water to the sugar mixture, stirring in half the flour, beat hard, add another third of water and the rest of the flour. Beat hard. Add rest of water and 2 eggs well beaten. Grease long baking-pan, turn in batter, bake in the slowest possible oven.