A couple of corrections...
- this lens is not a rapid rectilinear. Apparently I was misled on this point. It is definitely a wide angle, but I don't know the exact optical formula.
- the aperture numbering system is on the old "Uniform System" which does not correspond exactly to the f-stops that we have now. The aperture marked 16 equals f/16 in the modern system, but the numbers above that are not to be read exactly as indicated. The wheel number sequence is 16-32-64-128-256. In modern parlance, this equals f/16-f/22-f/32-f/45-f/64. I could give you a long explanation as to why. If you want it I would be happy to provide it once payment has been received : )