With a self-enforced stay at home I've been catching up on reading matter, currently books on the Southern Rly 'Leader'. The bit that puzzles me is that each loco had no less than 144 piston/cylinder rings for the sleeve valves - 24 for each cylinder. Plenty of photos showing the sleeve valves, but none with grooves to take the rings. So where did they fit? Enlightenment, anyone? A cylinder drawing would help - assuming one exists.