As you can see, water from the air condenses on this plate and runs off it into this receiver.
In winter, the inner surface of the steel frame gets so cold that water condenses on it.
The water then evaporates and condenses on the bottom of the covering glass.
Knapen's intention was that water should condense on the cool inner column.
If the conditions are right, the excess water will condense out of the air until the lower saturation point is reached.
The dew point is the temperature at which solid or liquid water will condense from the air.
When you bring it inside a warm house, water will condense on its surface.
(This is why water often condenses on the sides of the bottle and then freezes).
Replies: The water condenses on the surface, it just doesn't make a fog.
Nor does it change when water evaporates, or condenses into droplets.