Original vintage farming industry magazine ad for  PURINA MILLS of St. Louis, MO.  Make Your Hens Lay Winter Eggs with Purina Chicken Chowder.  A hen absorbs back into the system the yolks that are unlaid.  This makes her fat and stops egg production.  Fat hens are poor layers. Feed her high protein feed. Old 1918 color farm equipment and supplies advertisement, would display beautifully matted and framed.