This is odd
I was looking @ the rear cell on my B&L lens, and it's 23 1/4" f/l.
The front cell is 18 7/8" f/l.
The old B&L table never put a longer cell in the rear.
I got the camera from the original family owner, and it was apparently ordered this way in 1923.
Makes me wonder ... any thoughts on this anomaly?
This sounds suspiciously like a convertible lens. The front and rear elements used alone behind the shutter will give their marked focal lengths. The two together form a third focal length, shorter than the individual elements used separately. It may very well be the case that someone assembled them backwards.