Thomas Fowler Calculator - 1840
"Fowler's machine utilizes a simple mechanism to multiply or divide two numbers. The machine uses signed ternary, a variation of base three where each digit is represented by either "-", "0" or "+". This model is only a small portion of the machine Fowler envisioned. The capacity of this machine is seven places in the product, equivalent to a decimal value of 1093. Fowler planned a machine with 55 places, equivalent to a decimal capacity of 8.72 x 1025.

Fowler never documented his machine. He built a model of it, but it did not survive"


Source: Mark Glusker - Reconstruction of Thomas Fowler's calculating machine

X-Number World of Calculators