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In Which Hank is the Nerdiest Nerd

2015-02-27 · explainer · Hank · 3:59 · watch on YouTube

Topic: Science & nature (also: History & curiosities) · mode: Explainer

Hank takes apart an antique all-metal adding machine to learn how it carries digits, finds that a key-blocked gear and a pin released at zero do the work, and praises the beauty of its hand-powered design.

What is said

The parts of the video and what is said in each (★ — how much it matters to the video).

00:00:00 — Greeting; Hank found an all-metal mechanical adding machine at an antique mall and brought it home to take apart

  • ★★ Hank says he found a thing at an antique mall that amazed him so much he had to take it apart, and it is now in his home. — 00:00:04
  • ★★ Hank says the machine weighs at least 25 pounds, is made entirely of metal and can add and subtract, and only sort of multiply. — 00:00:12
  • ★★ Hank says that when it was purchased the machine probably cost about as much as a really nice laptop today. (hedged) — 00:00:25

00:00:34 — The puzzle: adding one cent to 99 cents rolls over to a dollar; how does a mere machine carry the digit?

  • ★★ Hank says that the machine carrying a digit forward when 1 cent is added to 99 cents amazes him: how does a mere machine figure that out? — 00:00:38

00:01:17 — Taking it apart: fuzz like a dead animal, a 1980 dime, individually stamped parts, stuck flat-head screws

  • ★ Opening the machine, Hank finds fuzz he jokes is a dead animal and a 1980 dime rolling around inside, 'so it's not that old'. (playful) — 00:01:28

00:02:22 — Figured out: the key blocks the gear that turns the number wheel; 1930s factory oil; a pin freed at zero advances the next digit

  • ★★★ Hank explains that pressing a key pushes a lever that frees the gear turning the number wheel, and the pressed key blocks it at a point, so the wheel moves by that key's value. — 00:02:37
  • ★ Hank says the oil on his fingers was put on the machine by someone in a factory in the 1930s. — 00:03:06
  • ★★★ Hank explains the carry: at zero a notch holds a pin, and when the pin is moved out of the way the next wheel automatically advances; 'that pin is the secret'. — 00:03:18

00:03:28 — The beauty of its hand-cranked functionality and thanks to the forgotten people who made such devices; sign-off

  • ★★ Hank says it is the kind of thing we would never make today, but its hand-cranked functionality has a beauty he is a big fan of. — 00:03:28
  • ★★ Hank thanks the people, whose names we won't remember, who put their time and energy into creating these devices. — 00:03:41

In the description and comments

  • ★ The description jokes that Hank has been declared winner of the International Competition for Nerdiest Nerd. (playful) — video description

Threads in this video

Where the stories that moved here went next

Mentioned

Central: Carry (arithmetic) · RC Allen 805

Also: nerd

Only in the description or credits: Enigma machine · Games With Hank · Numberphile

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