Beat egg whites until stiff, then add two cups sugar and beat until it forms peaks. Set aside.

Beat egg yolks with remaining sugar until lemon colored. Gradually add oil, cocoa, vanilla and lemon. Fold into beaten egg whites.

Add flour and baking powder, alternating with juice and water. Mix until smooth.

Pour into the prepared baking pan. Bake for one hour.

Preheat oven to 350 degrees Fahrenheit. Line a 10- x 16-inch baking pan.