[ale] Engineering Archaeology

[DjPfulio at jdpfu.com]

Sounds like the movie Office Space.

On January 18, 2026 6:51:02 PM EST, "Jon "maddog" Hall via Ale" <ale at ale.org> wrote:
>Years ago there was a very famous case of a computer programmer that
>"misdirected" a lot of money by truncating fractions of a cent, instead of
>rounding, and storing those fractions of a cent into their own account.
>This has come to be known as "salami slicing" and is a lot harder to do
>with modern accounting systems.
>
>md
>
>On Sun, Jan 18, 2026 at 11:51 AM Jeff Lightner via Ale <ale at ale.org> wrote:
>
>> I owned a slide rule in high school but electronic calculators were around
>> by the time I was a senior so I was never terribly proficient with it.
>>
>> The well to do kids were buying the high end TI calculators but I could
>> only afford a model with basic functionality.   It weighed a lot and the
>> battery didn't last long.   That was back in the days they would blank the
>> display after a few seconds of inactivity, trying to preserve battery.
>>
>> It was just as well though.   In my math and science classes we weren't
>> allowed to use devices when doing calculations on tests so it forced me to
>> do things by hand.
>>
>> Later in my hospitality/accounting career they initially didn't have
>> electronic or computerized systems early on.   Many of the financial books
>> and reporting I did were done by hand.  As time went by electronic systems
>> appeared and quickly evolved to computerized systems.    I always had to
>> laugh when the computer went down as co-workers would say we couldn't check
>> people in or out.   I explained that hotels actually existed long before
>> such systems so it was in fact possible.
>>
>> -----Original Message-----
>> From: Ale <ale-bounces at ale.org> On Behalf Of jon.maddog.hall--- via Ale
>> Sent: Sunday, January 11, 2026 1:44 PM
>> To: Atlanta Linux Enthusiasts <ale at ale.org>
>> Cc: jon.maddog.hall at gmail.com <jonhall80 at comcast.net>
>> Subject: Re: [ale] Engineering Archaeology
>>
>>
>>
>> "If we applied such logic to when we were starting out - "slide rules work
>> just fine, don't need no electricity, storage, keyboards, monitors, etc."
>>
>> Slide rules are an interesting example. Stop and think about the
>> incredible application of logarithms being painted on two sticks, then
>> slide those sticks back and forth to be able to multiply two numbers via
>> adding two logarithms of them.
>>
>> Genius.
>>
>> And a fine example of analog mathematics being able to solve engineering
>> issues.
>>
>> Usually only used to calculate to three levels of precision, they were
>> "good enough" to do the calculations in an age where three levels of
>> precision was about all we could do in any type of manufacturing....so why
>> calculate to any greater precision, whether you are manufacturing a door
>> knob or a bridge?
>>
>> Fast forward to floating point arithmetic in a computer.   How many of us
>> have fallen into the trap of trying to "equate" two floating point numbers,
>> only to realize that "two" really has a value of
>> "1.999999..something-mumble"
>>
>> When I was teaching at Hartford State Technical College in 1975 the school
>> store was cleaning out their inventory and found about ten beautiful
>> "Aristo-Multilog Slide Rules", still in their box, complete with leather
>> carrying case and instructions.
>>
>> The store was selling them for five dollars each, down from their original
>> price that was probably close to 100 dollars.   I bought all ten, then gave
>> them out as prizes to good students, showing them how to use them and
>> explaining the significance in computer science.  I have two left.
>>
>> I did not expect the students to become as expert at using the slide rule
>> as I was, but I was happy to see that they understood the significance of
>> the lesson
>>
>> md
>>
>> > On 01/10/2026 8:36 PM EST Ron via Ale <ale at ale.org> wrote:
>> >
>> >
>> > Jeff Lightner via Ale wrote on 2026-01-10 14:50:
>> >
>> > > In my later years when I would speak to people about “the old days”
>> > > and things such as RS232-C and/or Hayes modem commands I realized
>> > > that while it was likely true I’d forget much of the detail it
>> > > didn’t mean younger folks would never know more than I’d forgotten.
>> > > They would instead have no need for what I’d forgotten (for the most
>> > > part) and eventually would learn things I’d never learn.
>> >
>> > Insightful comment.
>> >
>> > Of course, usual disclaimers of "not everyone, not always, not
>> > everything" apply:
>> >
>> > The "kids today" are learning lots of great new things and pushing
>> > boundaries in new directions. They're exploring new ways to do stuff
>> > and aren't sold on "we've always done it this way, so we should
>> > continue to do it this way".
>> >
>> >
>> > Too often I see that attitude by other, fellow tech old-timers.
>> >
>> >
>> > If we applied such logic to when we were starting out - "slide rules
>> > work just fine, don't need no electricity, storage, keyboards,
>> > monitors, etc." - I'm sure most of us would've found it unconvincing.
>> >
>> >
>> > Let them have their chance, some ideas will work, some won't, and it's
>> > their world now.
>> >
>> >
>> > Anyway, appreciate the thought provoking post.
>> >
>> > _______________________________________________
>> > Ale mailing list
>> > Ale at ale.org
>> > https://mail.ale.org/mailman/listinfo/ale
>> > See JOBS, ANNOUNCE and SCHOOLS lists at
>> > http://mail.ale.org/mailman/listinfo
>>
>> _______________________________________________
>> Ale mailing list
>> Ale at ale.org
>> https://mail.ale.org/mailman/listinfo/ale
>> See JOBS, ANNOUNCE and SCHOOLS lists at
>> http://mail.ale.org/mailman/listinfo
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.ale.org/pipermail/ale/attachments/20260119/4bafa54a/attachment.htm>