Glasgowken, I must tell you a story told to me by the Janny in a school I taught in years ago.
Ron started his working life on the Glasgow trolley buses as a conductor. On his first day his bus was going to the terminus at Riddrie library. When it got there, the driver told Ron to change the direction of the frog (the pole that hung onto the electric wires up above and powered the trolley bus). The driver then went off to use the toilet nearby.
Ron got off the bus and looked up at the frog. How was he going to move it to face the other way? How could he get up to it? He took off his cap and jacket as they were brand new, and he didn't want them dirtied on his first day. Then he slowly and gingerly set about climbing onto the roof of the bus. When he got there, watched by all the folk at the bus stop, he carefully unhooked the frog and re-attached it at the other end. The queue applauded heartily as Ron carefully climbed down.
Just then, the driver re-appeared and slapped Ron across the head!
"Ya daft bugger!" he cried. "Look!" and he pointed to a long pole on the side of the bus. "Ye use that, ya eagit!"
Poor Ron! He was covered in thick, greasy, black muck and all the spectators gave him a hard time. They knew about the Changing Of The Frog, but enjoyed his antics too much to tell him!