I can't remember whether N.P.C. were living at Green Close or Crow Nest, but I well remember hearing tales of a cave system inside Silverband Mine, quite complex and with several interesting features. One day, Jack Myers gave me one of his inferior creatures looks and at the same time invited me to spend one night and a day in Silverband. This was immediately accepted, and arrangements were made to drive up to Appleby and across to Cross Fell. Jack informed me that the mine was closed and was in a very unstable condition, also we were not to be seen entering by the people at the weather station. So at dusk, we left the car at some safe distance from the entrance and made our way like thieves in the night until we reached a gate supposedly barring the way. This we easily passed by crawling on our stomachs. Once inside we walked along the rail tracks for some considerable distance whereupon Jack said that this was the spot to stop and feed and sleep. Out came the grub, candles and a bottle of wine. I'd never seen such luxury below ground.
After we'd wined and dined and had a natter about what we were going to see, he gave me one of his famous "Your education is about to be furthered" looks and proceeded to make his bed across the rails using one rail for a pillow and saying how comfortable it was. So I copied the bedding formula, and spent a very uncomfortable night interspersed with thoughts of someone driving a train over our necks. I was glad to get up to have a rest.
As usual, Jack was very organised. Breakfast was soon over and we proceeded through what seemed to me to be miles of very unstable mine working with lots of crystals growing in the roof. I think Jack said they were barytes (please check) - (check it yourself - Ed) many were coloured and well worth a photograph. It soon became clear why he'd brought me along. I was to be a photographer's labourer. To make matters worse he used his special flashless smokepowder and nearly killed me.
After a while he told me that he would show me cave passages that were formed during the time that the passages were completely flooded and which were subsequently drained during mining operations. He actually said "Phreatic caves with no vadose modification". I had often wondered how it was possible to have long, parallel passages developing from a narrow fissure. The acid water entering the crack would have used up its powers to solvate the rock very early on and should have formed passages big at the entrance tapering off towards the outlet. Here was one possible answer. The walls of the passage were like a crystalline hedgehog with the limestone walls about two inches below a maze of insoluble projections. These projections kept the slow-flowing acid water away from the limestone walls enabling the acidity to penetrate further into the passage until new surfaces became etched out thus enabling the acid water to penetrate further and further.
The floors of the tunnel were inches deep in debris that had been etched out of the walls. Jack was quite proud to have destroyed a bit more of my ignorance. In the vadose caves of my experience the evidence would have been washed away as the passages evolved from phreatic to vadose. In all, a very enjoyable trip.