Napier's Bones with Storage Box

Napier's Bones is a system to simplify the process of multiplying large numbers, originally invented by John Napier in the 17th century. The bones are also used for division and finding square roots with a high degree of precision. Procedures are available on the [Wikipedia article](https://en.wikipedia.org/wiki/Napier%27s_bones).

My version includes a row selector that mates with the tray, and a storage box that uses the tray as a sliding lid. The storage box holds three copies of each numbered bone that are easily accessed by pressing down on either end to pop them out of their slots. The special square root bone and row selector also store neatly in the box. The lid is retained by small nubbins when closed but is very easy to remove by lifting from the notch.

Prints without supports. Insert a filament change with your slicer to make the numbers easier to see. Use a brim if your filament is prone to warping.

Happy printing!