This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
Use a paste made of vinegar and baking soda with a small amount of salt added. The ingredients should he mixed in a large dish and applied to the wall with a cloth. The grease and fly specks as well as the carbon deposits from kitchen smoke are quickly removed. The mixture is harmless. After the wall is thoroughly cleaned, it should be washed with warm water and soap, then dried with a cloth. The mixture works equally well on enameled baths and glass or white porcelain.