Bugbear finds a scaling rule of some sort:

B18 3/4 1.0 B19 1/2 .96 B20 1/2 .9231
         B21 .888 B21 3/4 .8627 B22 1/2 .834 B23 1/4 .808
         B22 .7843 B24 3/4 .7582

It will not have escaped your attention that the B scale numbers are
inversely proportional to the length of the marked intervals; e.g.,
18.75*1 is (within reasonable measuring tolerance) = 19.5*.96 = 20.5
*.9231, etc.

And no, I don't have a clue what that adds to the understanding of this
rule--just thought I'd make the point explicitly.

John Wadsworth, in Delhi, NY, who has a mysterious set of Starrett scale
rules he ought to post about


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