Lady Knox Geyser,at Wai - O- Tapu, 27 km.from Rotorau, the ranger puts soap flakes down the geyser to get it to erupt.
This breaks the surface tension between the cold and very hot water,a few minutes latter and bingo a geyser,right on time.
Sort of like putting a Polo Mint into a bottle of Coke, in the science lab at school. Haven't spent much time in the Hen's Head - very pretty Country - To be truthful I don't like being shaken by the sub terranean forces.
Possum; AKA:- Ali El-Aziz Mohamed Gundawiathan
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