Calculator I built that is a copy of Napier’s “bones” calculator that is a rendition of a calculator from ancient Mesopotamia. This calculator can compute numbers as large as 10^18 which is 1 million trillion. It was used for trade in Mesopotamia and for tax calculations and commodities in Europe from 1600 onward. It also does square and cube roots or any integer nth root that I have a bar for. I got so fast with this I could beat an electronic calculator with high precision. For division, it computes fractional remainders because the decimal point was not invented or in widespread use until the 19th century. Napier invented the log scale and many other common math expressions we use today. The term “counter top” refers historically to this machine, and the operator of the device was done by… an accountant !

I did this build on a whim after seeing one in a museum and becoming obsessed with it. I’m an amateur mathematician and I’m a trustee at a prestigious math institute where I get to mingle with famous (real) mathematicians like Roger Penrose, Jim Simons, Dave Eisenbud and my math mentor Elwyn Berlekamp. Elwyn hired me back in the 80s to work on the film “Terminator 2” for which he principally designed the Oscar winning sound system. Elwyn got me the gig at MSRI (the math institute) after I left Oculus. I stayed in touch with Elwyn for 35 years until his passing in 2019.