Sponge Cake

Directions

1. 1
   Beat egg whites very stiff and add 1/2 sugar.
2. 2
   Beat egg yolks until thick and lemon color.
3. 3
   Add remainder of sugar, lemon juice and rind; fold whites into yolk mixture.
4. 4
   Sift flour and salt; fold into egg mixture.
5. 5
   Bake in ungreased pan for 1 hour.
6. 6
   First 15 minutes bake at 300°, gradually increase temperature to 350° for the last 45 minutes.