The air duct in our living room

My Grandfather used to work on the railroad.  He was the guy who was on the caboose. Back then, you had to steer the caboose as well as it was responsible for some of the braking.  My grandpa used to say how he could feel the heat coming off the metal wheels as they screeched to a stop. I used to prefer sitting and listening to him talk about it all when he was younger.  One of his number one topics was about the heating system that he had in the house. I remember that old heating system. It was in the family room. They burned coal and there was always a giant bucket of coal on the floor next to the good old heating system. There was a big air vent that went through the floor, that was directly above the heating system. This allowed the heat to flow up into the upstairs, which is where everyone slept. I remember being upstairs as well as listening to everyone downstairs as they talked together. I often thought that no one could see me because I was off to the side of the air vent. When I got older, I realized they could see my cousin as well as I as all of us sat up there.  My Grandma and Grandfather thought it was funny. They would make a lot of cool things to eat as well as wait for one of us to come down as well as say all of us had to go over to the bathroom as well as then they would ask if we wanted some of their goodies. I miss that old heating system as well as most especially, I really miss that air vent.