before slide rulesEdmund Gunter was a clergyman and mathematician who is known for his survey chain, but also invented a "gunter", a mechanical device...

better than a robotMy helper beats a robot all to pieces, another registered land surveyor 🙂 plus he helps me carry gear,offers insight and the occa...

How about using a tag that they use to affix to cattle ears, fastened the same way and with the same tool.