IBM 1620; was: Early Programming Books

Van Snyder van.snyder at
Mon Jun 21 18:00:11 CDT 2021

On Mon, 2021-06-21 at 17:26 -0400, William Donzelli via cctalk wrote:
> > Of course, nowadays, the old R22 systems are being refilled with
> > purified propane, called R290.  Cheap, with better thermal properties
> > than R22, but probably not legal when LCM picked up the 6500.
> When cleaning out a 3rd party CDC dealer quite a few years back, he
> remarked that the CDC machines going way back all the way to the 800s
> were fantastically unpicky about how they were cooled. He just used a
> garden hose connected to the building potable water, and if the
> machine under test needed more coolant because it was running warm, it
> just pumped more supply. Heated waste water went down the drain.
> This unlike the IBM water machines.

I was once told that the most valuable guy in a Honeywell 6080 Multics
shop was the plumber.

> --
> Will

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