Sponge Cake

From 1922:

This is the most inexpensive recipe I have, 5, 6, and even 7 eggs being used in sponge cake. This recipe contains 3, and, in addition, 4 tablespoonfuls each flour and sugar, and a wee pinch of bi-carbonate of coda. Boat the eggs and sugar to a cream, beating for quite 15 minutes; then add flour and soda and mix all as quickly as possible. Put it into a tin lined with buttered paper sprinkled with sugar, and bake in a good oven at once. Either of these cakes may be covered with simple icing, and will be quite suitable for a wee girl’s birthday cake.