11 Jan
2023
11 Jan
'23
8:25 a.m.
On 2023-01-11 12:44 a.m., Joe Harrington via Contra Callers wrote:
I heard recently (I believe from Angela DeCarlis) of a mechanical sorting
system based on the Jacquard loom concept that became the Hollerith punched
card system. I've never seen it in use. Does anyone do this?
See https://en.wikipedia.org/wiki/Edge-notched_card
[Ah, Jeff Kaufman beat me to it.]
Figure out the ten or so characteristics you might
want to sort on. For
example, easy, medium, hard, bouncy, flowy, separates partners, sweetheart
(keeps partners together), etc. Take a stack of cards and drill holes near
the bottom edge, one per characteristic (you can drill a stack of cards if
you sandwich them between wood and clamp them). Now, on a given card, punch
out the rest of the paper between the hole and the edge of the card for each
hole the card DOESN'T match.
Alternatively, you could punch out the margin when it *does* match (which
would probably be less work). Then in the selection procedure, the cards
that fall out (as opposed to the ones that stay on the needle) are the
selected ones.
[...]
Good hole alignment and clean punching would matter, I think. If you are a
real dance sorting fanatic, you could get like 30 holes around the card
edges, but that would limit the writing space.
Back when I was young and had lots of time (and no computer), I made a deck
of edge-notched cards to 'play' the game Mastermind:
https://en.wikipedia.org/wiki/Mastermind_(board_game)
(4 pegs of 6 possible colors, so 1296 cards, each with 24 holes and 4
notches.) As I recall, during the selection procedure, cards with a notch at
the selected hole (which *should* fall out) would sometimes 'stay on' the
needle just from friction with the neighboring cards. So I'd have to jostle
the deck a bit to shake those loose.
Also, V-shaped notches increased the chances that a card would fall out when
it should.
One way to avoid these problems is to have two opposite sets of holes, with
complementary notches. In the selection procedure, you use two needles,
placed in complementary holes, and you pull them apart to separate the cards
you want from the ones you don't.
-Michael