How much memory fit in a six-foot-tall cabinet in 1964?

IBM’s site has a blurb about the IBM 2361 core storage unit.

In each 2361, almost 20 million ferrite cores — tiny doughnut-shaped objects, each about the size of a pinhead — were strung in two-wire networks and packaged, with associated circuitry, into a cabinet only five by [two and a half] feet and less than six feet tall. The first memory was installed for use in a complex of five powerful IBM 7094 Model II data processing systems. Four additional memories were added to the NASA Real Time Computer Complex (RTCC).

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The 2361′s design provided for storage of 524,000 36-bit words and a total cycle time of eight microseconds in each memory. The 2361 was the first IBM memory to use two-wire core storage to increase storage capacity, improve performance and reduce unit size.

Now, I don’t know if my math is correct, but here’s what it shows. 524,000 36-bit words means 18,864,000 bits. According to Google, 18 864 000 bits = 2.24876404 megabytes.

2.2 MB is nothing today. Imagine it! A box 5 ft x 2.5 ft x 6 ft, and it stores less than two standard 3.5″ floppy disks!
IBM Archives

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