It’s defined here Rhiannon. http://www.britishdowsers.org/EEG_site/Glossary/page1.shtml I must say I couldn't see why there would be a spring almost on top of a hill, like WKLB is but it says “It is thought that the water is forced to rise up the vertical fissure due to a narrowing of the feeder stream.”

Is that right? If a subterranean stream encounters a narrow bit wouldn’t the water just back up rather than squirt upwards? It happens with artesian wells because the water table is higher than the well but that doesn’t apply at WKLB does it?