How can one explain the Napierian logarithm without calculus?
What's wrong with Mathworld's page?
What's with the seemingly arbitrary power of 7; is that an archaic artifact of Napier's? Can one design a slide rule, in theory, that calculates powers by addition of the logarithm of logarithms?
Napier's logarithm isn't the logarithm we use today -- I would assume the 7 made his tables of logarithms numerically convenient for the numbers of interest.
You can compute powers with an ordinary slide rule:
log (a^b) = b * log a
and we know how to multiply with a slide rule.
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