Cincinnati Children's Archives on Twitter: "The Archives hold two early electric calculators, Monroe Model 88N-213 and a Marchant, the supercomputers of their time. The Monroematic, made in the 1950's was used in
Pamphlet, Instructions for Operating Monroe-Matic CAA Model Monroe Calculator | National Museum of American History
![1954 Monro Matic Simplex 8N Calculator Vintage Look Funny Aluminum Metal Sign Funny Easy to Mount Indoor & Outdoor Use 8 x 12 : Amazon.ca: Office Products 1954 Monro Matic Simplex 8N Calculator Vintage Look Funny Aluminum Metal Sign Funny Easy to Mount Indoor & Outdoor Use 8 x 12 : Amazon.ca: Office Products](https://m.media-amazon.com/images/I/81k1jEneuzL._AC_SL1500_.jpg)