Ever seen one of these??

was there like a drying shelf on the bottom? looks like there are lugs to hold a shelf on the bottom.

Is that HW or Steam? The manual vent looks like it would be water. Might make a nice seat on a cold day……..for a short time

Or a piece of steel between the lugs you could cook breakfast on it.

I wonder what the purpose of the step in it was?

a "piddle catcher"!

No..."I think um in love...." Eddie Money...Mad Dog

For @Stet, Back in the day, we would need to work (or play) in the snow. We would wear something my father called galoshes over our shoes to protect them from the wet snow and ice. At the end of the day, that shelf at the bottom of the radiator might be a nice place to dry out your shoes and/or galoshes so they were dry for the next day!

As far as @psb75's contraption is concerned, That might be a Semi-automatic Humidifier. As the trough dries out, you just open the bleed port to refill for more humidity. It might be a once an evening thing. But eventually you would need to add water to the boiler if there was no auto feed in the basement.