My determination to find the profound in every aspect of European daily life led me to notice that the main fountain in Tivoli was designed by Niels Bohr!
Niels was one of the fathers of Quantum Mechanics, a branch of physics which describes the behaviour of sub-atomic particles. Very important stuff for Nuclear Physics and Astronomers, not understood one whit by most of the world. I imagined that Niels was attempting to illuminate an aspect of his arcane mathematics with these objects:
They are vertical glass tubes filled with water and bubbles of air rising through them. Mmmm... I stood there and pondered. Pondered two questions. Firstly what is Quantum Mechanics about?, and secondly: what was Niels trying to demonstrate here ?
In answer to the first I managed to dredge up snippets from Fritjov Capra's "The Tao of Physics" which had shed some light on the subject for me many years back. Wave/particle duality, 'fuzziness', mmmm not much more sprung to mind except a "quant"ity of mental fuzziness. So to the second question - what on earth was Niels trying to display?
As I watched the bubbles gurgling upward, the only thing that seemed relevant was the mathematics of turbulence. Very complicated stuff of which I understand nothing but I know folks who use it daily as they investigate airflow over aircraft wings and the flow baby food through pipes. Perhaps Niels was interested in turbulence? The fountain is in front of the "Moorish Palace" - could it be inspired by the fountains and flowing water often found in Moorish Palaces...?
The tubes looked like the air filters you see in aquariums.
Later on I looked in my Guide to Denmark and found this quote:
"This is an unusual sculpture designed by the Danish Physicist Niels Bohr. Bohr was inspired by gazing at his aquarium."