Preheat oven to 350 degrees. Stir shortening, vanilla and salt together. Add 1/2 cup sugar. Cream until light. Add cocoa. Mix. Add flour, water and soda water. Beat egg whites and add 1⁄2 cup sugar. Fold into batter. Line 8” or 9” round cake pans with wax paper. Bake for 25 minutes.