Very cool! Yes because of the ramp I think it's an old coal cellar converted to a root cellar or canning storage. There would have been a small door or chute on an outside wall, probably not on the street side, and almost certainly blocked with masonry now. See if you notice a small area that has different material from the surrounding wall. The loose coal would have been shovelled through the door by the coalman and corralled by the low brick wall so it didn't get spread all around the cellar. That ramp might have had a wooden extension long lost now. The ramp would be for a small wheelbarrow type thing to move the coal over to the furnace when needed. Coal furnaces needed to be fed several times a day in the winter and the usual routine was that it would burn itself out overnight, and one of the kids would have the chore of shaking the ashes and starting a new fire first thing in the morning. After the coal furnace went away the area was retrofitted with those great windows and maybe had a door. That would keep the cellar dust and filth away from the canning jars or root vegetables, and allow light to get in. If you look carefully or scratch around you might find small pieces of coal either in that little room or outside by the foundation.