'Keuffel & Esser, the dominant maker of these calculating devices, made its last one in 1975'
slide rule
FORMER TECHNOLOGY: Keuffel & Esser, the dominant maker of these calculating devices, made its last one in 1975
Keuffel & Esser, the dominant maker of these calculating devices, made its last one in 1975
Keuffel & Esser, the dominant maker of these calculating devices, made its last one in 1975
FORMER TECHNOLOGY
slide rule
FORMER TECHNOLOGY