Light code ornament in the hallway of Sonneveld House. The light code ornaments are part of an electric doorbell system. The ornaments are half built into the wall. The ornaments have two or three built-in buzzers with corresponding lights. The buzzers vary in pitch. The lights have a yellow, green or red window. Red and green: front and back door. Yellow: dining table bell. Only the ornament of the kitchen has all three buzzers and lights. This system allowed the servants in the house to immediately see where their help was requested.