Napier's bones calculating device - GIF

[WmRMeyers]

In the seventeenth century the ability to multiply was probably rare so the bones may have helped to reduce errors although, IMO, the procedure is complex enough to be easily confused.

Napier's invention of logarithms was far more useful. We can thank him for the decimal point as well.

This reminds me of an old mathematician's joke...

Noah has finally beached the ark and the animals are being released to repopulate the world. The mating is going well but Noah's son reports that the adders are not getting it on. "Not a problem" says Noah and throws them on the dining table made of oak logs, whereupon they begin making baby adders.

Noah's son is astounded and asks his dad why that worked.

Noah responds, "Don't you know, even adders can multiply on a log table?"

I'll get my hat now.

I was promised that there would be no math! Rotten teacher lied! Though it was probably really too late for me anyway.

Bill