This page has nice pictures of two types of memory used in some tabletop calculators in the 60s. (I find the mechanical delay line memory especially fascinating

This page has nice pictures of two types of memory used in some tabletop calculators in the 60s. (I find the mechanical delay line memory especially fascinating.) http://www.vintagecalculators.com/html/calculator_memory_technologies.html http://www.vintagecalculators.com/html/calculator_memory_tec...