The MagicBrain Calculator was manufactured in 1955 by the Chadwick Company, this early calculator was operated using a stylus, and could perform addition, subtraction and multiplication calculation
Powerhouse Collection - Two Magic Brain pocket calculators
Slide calculator - Wikipedia
Is the human brain more like a digital computer, an analogue computer, or a combination of both? - Quora
Magic-Brain Calculator (2) - Calculator - Computing History
The Magic Brain Calculator – I Remember JFK: A Baby Boomer's Pleasant Reminiscing Spot
Calculator - Exactus Mini-Add, Pocket Model, circa 1950
Slide Rules & Calculators — The National Museum of Computing
Pocket Calculator Isn't A Brain Or Magic
Life is math, a Calculator is what you need!
From Historical Artifacts to Natural Treasures, These Discoveries Were Found in the Least Expected Places