My original interest in abaci started in Tokyo in 1964 when I bought a Soroban with Kojima’s book "The Japanese Abacus: Its Use and Theory". That sparked my interest in computers.
After getting my M.Eng.(Elect.) at Cornell, my 30 year career included designing and constructing nuclear power plants, missile systems computer programming, and industrial and engineering computer systems sales and systems engineering.
Deciding to become a high school math teacher at the end of 2000, I took a History of Math course as part of my M.Ed. Program at UMassLowell. I was struck by how easy it would be to use ancient Roman, Greek, Egyptian, and Babylonian numerals to record abaci calculation results. Prof. Gonzalez said, "Yes, but how would you do multiplication and division?"
So as a hobby, I've worked the last 9 years to rediscovered the schematics and programming rules of the computers the Ancients used to design their weapons, do their accounting, and in general support and power the greatest empires in human history.
For work, I teaches precalculus and calculus at Lowell High School, Lowell, MA. http://sks23cu.net/MT.