It's funny when a book this old calls something "old-fashioned." It was hand-written in 1938.
Old-Fashioned Jelly Roll
5 eggs
1 cup sugar
1 teaspoon vanilla
2 cups flour
2 teaspoons KC (not sure what that is, I'm guessing it's Baking Powder.)
Beat eggs to a lemon color. Gradually add sugar, vanilla, flour, and baking powder. Roll out and bake in hot oven. Have a warm damp towel ready. When roll is done, roll up in towel and let stand awhile; then unroll and spread with jelly then roll up again. This will prevent the roll from cracking.
I'm guessing the modern baking directions are at 425 degrees for 15-20 minutes, like most pastries.