I have made a reasonable facsimile of this sprite paper (US letter size). Please feel free to use.

This may be my last Chisanbop book to archive. I just received in the mail a copy of "Mathpattes", presented as a french language version of Ed Lieberthal's "Complete book of Fingermath". Published in Switzerland, 1986 #chisanbop archive.org/details/math...

Pascal's 1630 Machine, and the knockoffs! Pascaline Review www.youtube.com/watch?v=CROr...

Strange phenomenon: Every time I post a new video, I lose subscribers. My interpretation: There are some subscribers who aren't really into me anymore. But they don't seek out my channel just to unsubscribe. They will only unsubscribe when they are reminded of me, which only happens when I post.

New video: I went to see the Pascaline! They did not let me touch it. youtu.be/CROrLQpN6dc

Just posted at @archive.org: instructions for the transparent "Pascal-type calculator" (also called the SEE calculator). archive.org/details/pasc...

My dad took me down to the #nokings

Ladies: if he says "heighth" he aint the one

Now available! (but pretty boring tbh) archive.org/details/stag...

On an auction site someone is claiming to have a Comptometer for sale, but the picture is some kind of AI-generated rubbish. I don't see the point, but it makes for a fun game: How many errors can you spot?

The pascaline is in New York! No original stylus though 👎

Just received in the mail the ultimate Chisanbop holy grail- the blue “Stage 2” book by Pai and Lieberthal! I thought it was never published- I said in my video it was never written. But Randi found a copy at her mom’s house! Thanks again Randi!

New archival project: the Lawson Perspective Charts! It's a set of big (25x22in) charts for perspective drawing. Eight charts, various angles to the plane & horizon. With original instructions! The highest quality scans I could muster. I'll make a video when I have time. @archive.org links below

I just realized this item will be on public display in New York next week! Look for me in the crowds! hope you get to try-before-you-buy

+1 vote for national apologies! This is what strength looks like, “Christian nation” bros apnews.com/article/sout...

don’t get any ideas

This morning, one of my students: "My roommate is in your other class! She says you're a great teacher."

An ORIGINAL Pascaline for sale- doesn’t even say how much for the shipping smh press.christies.com/la-pascaline...

An expository talk I gave yesterday about Nielsen Theory. Nine variations! Should be accessible to anyone with a little topology background. (fixed audio from prior upload) youtu.be/8tJVWOXV1GU

New gizmo: 4D tape measure youtube.com/shorts/f5oqK...

In Spain if there’s a fire you dump this giant bottle of sriracha on it.

Yesterday I checked out El Rasto market in Madrid. Highlights: - two auto-numbering Bates-type stamps - fancy old stapler - abacus-like shipping list thing

Today’s yard sale find: a curved aluminum ruler and French curve. Looks like they could do some damage.

Progress! I’m shocked- it wouldn’t do anything 10 minutes ago! I still don’t really know what all the buttons do…

New old adding machine seems jammed. Should be able to pop the case and figure it out, right?

@itsmebenmarsh.bsky.social Did you delete your substack? I know I'm slow but I was planning to read "Serpent on the Mount" after I finished my other book last night. But now I can't find it!

New sign on the office wall. Don’t make me point at it!

I am on the list! (My dad too!) Probably everybody who publishes math papers. But the journal publishers own all the rights, so I guess they are the ones who would be compensated in a settlement?

who hurt you bro?

Dae-Woong Lee, P. Christopher Staecker Homotopy equivalence of digital pictures in $\mathbb{Z}^2$ https://arxiv.org/abs/2509.03023

Math props in Batman: Arkham Knight. Classic NCR inspired- not interactable, and the buttons aren't even 3D-modeled! Just painted on. And honestly I'm not sure why this is even here- the game is set in "present day". Some lore I'm not privy to I guess.

As I was walking home today, I had this idea: Is it possible to turn a QR code into a Truchet tiling that's still a functioning QR code? Yep.

Too rich for me but this is wild! I didn’t know this existed. ebay.us/m/CqmsIC

I just received this amazing set of hand-crafted wooden Golomb Rulers from Todd Sanders. (I made the much more pedestrian 3d-printed stand.) Thanks so much @lackriver.bsky.social‬!

Why do they always say "am I being detained"? Who made them think this is some kind of magic word? Is it some kind of magic word?

Just saw this listing for a really cool machine- with the ORIGINAL box! I’ve never seen the box before. Didn’t know there was one. It’s plastic but I love this machine. ebay.us/m/P8HG6O

Bought two peaches

Spotted today: Royal typewriter with homemade cover, and box o horns

New video: A "Trade Stimulator" from the 1890s! The direct precursor to the slot machine, designed to be legally ambiguous. youtu.be/ghy68syYtC8

This weekend yard sale curiosities: fully automatic craps table? Royal typewriter, strange 4-color style stitch work, and an old stereoscopic photo set.

NCR electromechanical cash register in the wild in upstate NY. Still in use!

Original!

Seen on reddit- very cool idea www.reddit.com/r/Sliderules...

slide that decimal point over and we got a deal

Weekend flea finds: Labubu AND Lobobo, those squirts water toys, and Nemo from Finding Nemo. Nuthin good though

U admin: It's OK to reduce our library's physical collection- we have beautiful licensed eBooks! Those beautiful eBooks: (not downloadable)

some youtube guy just followed me @vsauce.bsky.social

“Staecker”. And “Korean finger counting method”? Have I taught you nothing?

There’s a set on eBay now! But $55 seems a bit much- you can get the whole box new for $75, minus 25% with my promo code!