MJ

Very interesting points. Thanks for them...

When you were posting the measurements of the passage I thought about measuring stairs;
carpenters divide the risers into the total height so they are all equal, and the runners into the total length so they are all equal, and the actual length of a staircase laid flat is...
whatever it is!

I wonder if the perhaps seked was the critical part of a sloped passage, not the final length?

Jammer