
How to Use a Differential Analyzer - janvdberg
https://twobithistory.org/2020/04/06/differential-analyzer.html
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tzs
This could use a lot more visual aids.

Here's a film that goes over a lot of the basics: "BASIC MECHANISMS IN FIRE
CONTROL COMPUTERS" [1]. It's a 1953 US Navy instructional film explaining how
mechanical fire control computers worked.

These machines took inputs giving the speed and direction the ship was
traveling, the speed and direction the target was moving, the distance and
direction to the target, the wind speed and direction, and other factors, and
computed how to aim the guns to shell the target.

[1]
[https://www.youtube.com/watch?v=gwf5mAlI7Ug](https://www.youtube.com/watch?v=gwf5mAlI7Ug)

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anitil
These old-school education videos are such a treat. One of my favorite is on
differential gearing -
[https://www.youtube.com/watch?v=K4JhruinbWc](https://www.youtube.com/watch?v=K4JhruinbWc)
(apologies about the clickbait title)

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Arnavion
[https://www.youtube.com/watch?v=yYAw79386WI](https://www.youtube.com/watch?v=yYAw79386WI)
is the non-clickbait-title version, hosted by the channel with other popular
recovered films in the same genre.

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peter_d_sherman
The Antikythera mechanism
([https://en.wikipedia.org/wiki/Antikythera_mechanism](https://en.wikipedia.org/wiki/Antikythera_mechanism))
"variously dated to about 87 BC,[22] or between 150 and 100 BC,[13] or to 205
BC,[23][24]" \-- may have been an early _differential analyzer_ \-- but that's
a hypothetical conjecture...

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mywittyname
I didn't see this covered in this article and I don't remember. How were the
coefficients for these differential equations calculated?

Also, how useful were these? Today, I think most people use vector field plots
because differential equations are so complicated. And I can't think of an
easy way to get from the output of this machine to a vector field.

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peter_d_sherman
Basically, a differential equation is just a description of a _rate of change_
in exact _mathematical terms_.

