While watching some of those documentaries, some of the steam engines have what I would refer to as "blinders". You know, those things you put on a horse when you don't want them looking anywhere except straight forward? Well, the steam engines have these big flat panels located on both sides of the front portion of the boiler just below the smoke stack like blinders. Clear as mud? It seems to be more common on engines not of the U.S. What are they called and what is their purpose?