## A Conversation for Peer Review

### A1093600 - Napier's Bones - a 17th-Century Calculation Aid

Gnomon - time to move on Started conversation 3 Weeks Ago

Entry: Napier's Bones - a 17th-Century Calculation Aid - A1093600

Author: Gnomon - time to move on - U151503

If this is thought to be suitable I can do better diagrams.

### A1093600 - Napier's Bones - a 17th-Century Calculation Aid

SashaQ - happysad Posted 3 Weeks Ago

Very interesting - thank you for writing this up for the Guide

Just one typo: "the left and right sides of the squares should not marked on the rods. " - should not be marked on the rods

"This arrangement ensures that a set of 10 rods can multiply any number of up to 4 digits in length and also many bigger numbers, as long as they don't have too many repeated digits." - I see that 10 4-sided rods can work with numbers less than 11,111, as there will be no more than 4 repeated digits. Perhaps that sentence could be made clearer about what 'bigger' and 'too many' mean.

The tables and photo of your Napier's Bones are very helpful, so I could visualise how it works in the examples

### A1093600 - Napier's Bones - a 17th-Century Calculation Aid

Gnomon - time to move on Posted 3 Weeks Ago

Thanks for your reply, Sasha.

I've fixed the typo.

It's not easy to specify exactly which long numbers can be represented. If a number has four 1s, for example, it can't also have four 2's because one of the 2s has already been used in the rods used for the four 1s. Rather than getting into an exact and boring specification, I had hoped that "not too many" would be enough information for most people.

Glad you like the diagrams.

### A1093600 - Napier's Bones - a 17th-Century Calculation Aid

SashaQ - happysad Posted 3 Weeks Ago

Aha - I was thinking about numbers with only five digits, but there will be some 10 digit numbers that 10 rods can work with, I see now

Key: Complain about this post

### A1093600 - Napier's Bones - a 17th-Century Calculation Aid

### More Conversations for Peer Review

- A88024250 - The 1939 Voyage of the St Louis, Refugee Ship [2]

Yesterday - A88014332 - How To Make Another Cat Toy [6]

Yesterday - A88023440 - 'The Complete and Utter History of Britain' - the Television Series [4]

Yesterday - A87986146 - Culture Clash: Japanese Anime's Influence from and Inspiration on Western Animation [6]

3 Days Ago - A88019553 - Roald Dahl Films: 2001-2020 [4]

4 Days Ago

### Write an Entry

"The Hitchhiker's Guide to the Galaxy is a wholly remarkable book. It has been compiled and recompiled many times and under many different editorships. It contains contributions from countless numbers of travellers and researchers."