thinking caps on ?

[Sumpter250]

I think that thermic siphons is the correct name

That'll learn me to be two days late and twenty bucks short!

I knew what the were, but that raises the question......and I don't have any reference material that mentions....when did syphons first come into use in steam locomotives? I am going to assume it was sometime around the advent of "superpower", and superheated steam. One of the benefits of thermic syphons, was the flow of recirculated water, would keep water over the crown sheet for a short time after the water level in the boiler dropped below the crown sheet. A safety feature, but definitely not an excuse for letting water level drop too far.