Set 1 on B to 0·23 on A, and under index of A read (1)/(0·23) = 4·35
on B.
Set 1 on C to 4·35 on E, and under 1·77 on C read 13·5 on E.
As with the Davis rule, the exponent scale C will be read as ⅒th its
face value if its R.H. index (10) is used in place of 1.