12.13.25: Happy Plus-Equals Day! #MathyDay

I'll take the opportunity to slip-in another #ShamelessPlug for my Mathy 2026 t-shirt, available at my Etsy shop: https://inspiredbymath.etsy.com

“Common People”!!!! You can hear Raina talk about this pick and the rest of her ballot on the livestream we had last night! #XPNcountdown #shamelessplug

RE: https://bsky.app/profile/did:plc:6x7zqldbl3qvjsj2fgwjgwuz/post/3m7pmidqw7222

#shamelessplug

Happy #ShamelessPlug Day!

I've added "Mathy 2026" t-shirts to my Etsy shop, just in time for holiday shopping ... and shipping!

https://inspiredbymath.etsy.com

The front features the digits of 2026 incorporated into an equation (oh-so-cleverly using an upside-down exclamation point to indicate the inverse-factorial function). The back lists over forty mathy dates (in MDY format ... sorry DMY-ers!).

Buy one of these, and you can ignore my #MathyDay posts for a full year.

Thanks for your support! :)

Happy #ShamelessPlug Day!

For when My Dear Aunt Sally enlists in Starfleet.

via my Etsy shop: https://inspiredbymath.etsy.com

I’m Not on Bluesky, but the Blog Is

I’m told that Ancient World Twitter was a thing and many of the same people have moved to Bluesky. I am an open web person not a corporate social media person, but if you prefer following this site on Bluesky to following it on RSS or by email or on Mastodon or by checking the URL every few days, there is a way. For a few months, it has been possible to follow bookandswordblog at https://bsky.app/profile/bookandswordblog.scholar.social.ap.brid.gy

I am not there! I am unlikely to see any likes or replies. I think all corporate social media funded by other people’s money will follow the same path as Facebook and Reddit and birdsite. I wonder if in a thousand years people will talk about microblogging like the Romans talked about the time they invited the Goths across the Danube then started to shake them down and enslave them without calling in the army first (or maybe like the Athenians talked about how they realized that speaking persuasively was a skill that could be taught for money). But if you want to follow this site on Bluesky, that is possible.

(scheduled 12 October 2025)

#mediaCriticism #modern #shamelessPlug #socialMedia

https://fogwave.printify.me/product/24023692/la-izquierda-libera-unisex-stonewash-tank-top ✊ #nokings #shamelessplug

Happy #ShamelessPlug Day!

Just a note that, if you like my triggy math-o-lantern t-shirt, then you might want to order one in the next day or two for delivery by Halloween. (In my experience, delivery takes about a week, but holiday shipping could cause delays.)

https://inspiredbymath.etsy.com

Thanks for your support! :)

Happy #ShamelessPlug Day!

I've added a triggy Halloween t-shirt to my Etsy shop. The design features a jack-o-lantern (math-o-lantern?) with iconic 30°-60°-90° and 45°-45°-90° right triangle eyes (with sides in proportion 1:√3:2 and 1:1:√2, of course), an equilateral triangle nose (1:1:1), and a sinusoidal grin (or grimace).

While I'm at it, I'll mention my design for fans of the Oxford/Harvard/serial comma. Pi-Tau COEXIST, Kangleroo, and other options also available.

https://inspiredbymath.etsy.com

Thanks for your support! (This is my only source of income at the moment.)

#pullrequest sent.

In other news, there's no tool quite like #Emacs #orgmode for gathering data from multiple sources in multiple formats and massaging it into an #estimate of effort for migrating a capability from one #vendor to another. #shamelessplug

Stitch Witches!

Halloween is coming and I thought I'd share these patterns which I think are pretty neat. Using glow in the dark threads they reveal themselves after lights out.

#ShamelessPlug

https://thesteadythread.com/collections/halloween/products/crystal-ball

https://thesteadythread.com/collections/halloween/products/halloween-blackwork-blackwork-ghost-pattern-pdf-modern-blackwork-embroidery

When the author regrets making that one character for the plot and now they’ve had enough 📖

Also, surprise plug! I have a brand new website with a blog I’ve been posting on for the last week:

https://thornwoodonline.wordpress.com

Head on over there to hear me ramble some more at the Bored Stiff Blog!
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#BookTok #writertok #blog #website #sketch #shamelessplug #characters

NULL Train demo is now available for Linux and SteamOS 🎉 Play the demo. Wishlist it: https://store.steampowered.com/app/3717840/NULL_Train/

#gamedev #gameplay #gameplayshorts #nulltrain #indiedevs #indiegamedev #steamgame #gamedemo #pixelart #wishlistideas #wishlist #roguelike #madeinhawaii #steamdeck #steamos #linux #shamelessplug

This is the second time I featured Raye on a playlist. The first time was last December’s jazz themed #ILikeToWatch playlist. She’s so gosh darned cute! 🥰

#ShamelessPlug
https://youtube.com/playlist?list=PLGkQ2CMSV2Yuq_3zWm65JPNngYzWwb5ba&si=1apj_XYyaKqS5Lu6

Yes, The Book of PF, 4th Edition Is Coming Soon https://nxdomain.no/~peter/yes_the_book_of_pf_4th_ed_is_coming.html (also tracked https://bsdly.blogspot.com/2025/07/yes-book-of-pf-4th-edition-is-coming.html) #openbsd #freebsd #bookofpf #pf #packetfilter #book #networking #security #freesoftware #libresoftware #shamelessplug @nostarch

@martinsteiger
Ich hab übrigens (hauptsächlich mal für mich selbst) das hier gegen #Phishing geschrieben:

https://chromewebstore.google.com/detail/urlscope/bmiajkolcloejdcanegkhdleglejdpgd

#shamelessplug

Finally, a #ShamelessPlug reminder:

My pi-and-tau t-shirts (and others) are available in the InspiredByMath Etsy shop.

https://inspiredbymath.etsy.com

Order today and I can pretty-much *guarantee* delivery in time for both #PiDay and #TauDay ... 2026.

(Also: Etsy is currently running a seller promotion reimbursing a bit on sales made through the link; this doesn't help *you*, but *I* could certainly use the extra buck! :)

Thanks for your support!

Aprovechando nuevo perfil y los impulsos. Sigan mi Pixelfed, pa' animarme a subir más fotos 👀
@conejoxm

#shamelessplug #pixelfed #fotografia

Some of My Recent Publications

In the past year a number of my academic publications have come out (it often takes years from submitting an article to an academic venue to seeing it in print because almost everyone involved is a volunteer with a demanding day job and no personal assistant to help them organize and focus). This week I would like to talk about them.

From the Tigris to Lydia

In an honourary volume for my Doktorvater Robert Rollinger I wrote about how Tissaphernes marched west after he drove the Ten Thousand into the mountains of Armenia to freeze. To my knowledge, nobody has considered this question at length. I talk about Hittite, Assyrian, and Roman geography, about how the mountain passes and river valleys channel travel, and about what made a route suitable for an army. I had to cross-reference place names in Turkish, Arabic, Greek, Latin, Akkadian, and Hittite and understand the startling ways in which the Turkish government has changed the geography by building concrete dams and widening narrows with dynamite. Studying this question made me think about how people who are not orientalists underestimate the Ancient Near Eastern approach to travel infrastructure. The kings of Egypt and West Asia did not build stone bridges or paved roads like the generals of the Romans, but they built and maintained dirt roads and pontoon bridges and storehouses where messengers could camp for the night, collect rations, and learn about the road ahead. Every storehouse would have had people who could read and write Aramaic so there was no need to accost goatherds and charcoal-burners and hope they shared a language with you and could tell you which fork of the road to take. This network has vanished because it consisted of people and parchment lists and mud-brick buildings, but it made travel an experience we would recognize, an experience totally unlike a Roman army stumbling through Germania.

“The Other Katabasis: Tissaphernes’ Route West After Cunaxa,” in Kai Ruffing, Brigitte Truschnegg, et al. eds., Navigating the Worlds of History. Studies in Honor of Robert Rollinger on the occasion of his 60th Birthday (Harrasowitz Verlag: Wiesbaden, 2024) pp. 975-992 https://www.jstor.org/stable/jj.20829413 is available to anyone who asks for a copy.

My public speaking skills have become rusty like the Seven Weapons of Erra, so I would like to record a version of this paper as a talk to practice my public speaking.

The Long History of Plywood Shields

I fulfilled a goal I have had for a very long time when I published an article in the Journal of Roman Military Equipment Studies. Most people think of plywood shields as a Roman technology used for the long scutum from about the Punic Wars to the third century CE, when it was replaced by shields that look a lot like Viking shields but even bigger. Plywood shields don’t split as easily as shields from a single layer of wood, but they are harder to make. The ancients did not have mills that unroll a log into a 1/8″ strip of timber like a student peeling a carrot, so they had to split wood into narrow strips by hand then glue them together like a sheet of papyrus . None of the plywood shields were known from the pagan Anglo-Saxon and Norse worlds, even though thousands of shields from those cultures have been excavated. However, plywood shields have been found in sites from the Greek world and La Tène “Celtic” Europe hundreds of years earlier, and they reappear in European archaeology after the year 1000. They may have been used in Scotland as late as the eighteenth century. Plywood shields were not a distinctive Roman technology, and have a long legacy in Europe.

I apply my trademark methods of combing written and archaeological evidence, and bringing together evidence for the same problem that is usually known by different groups of researchers.

This raises the question whether some of the East Roman or Frankish shields were made the exact same way as shields from graves in England or ship burials in Denmark. Were plywood shields reinvented in the second half of the middle ages, or did the technology survive in places where people did not bury their menfolk with shields for archaeologists to study? Shields in Carolingian and Christian Roman art often look domed, but the Viking shields from Denmark are flat, and so are the pagan Roman shields from Dura Europus in Syria.

“Plywood shields in European history,” Journal of Roman Military Equipment Studies 23/24 (2022/23) pp. 9-23 is available for anyone who asks for a copy. I have not received my paper copy yet because I misplaced an email.

Aketons, Gambesons, Jupons, and Pourpoints

The first part of my study of linen armour in the second half of the middle ages has also been printed. Back in 2019 I started to get ready for a business idea by collecting evidence for linen armour in Catholic Europe between the years 1000 and 1350. It turned out that there are whole libraries of texts that nobody interested in warfare or material culture has ever discussed. Medieval terms which military historians take for granted, like “linen armour” (armour of many layers of fabric, or a few layers with scraps or unspun fibre quilted between) or “cuirie” (hardened leather breastplate) are not known by all dress and textile specialists, even though the same workers made quilted bedcovers and quilted coats for soldiers. So I mined every dictionary of medieval languages and encyclopedia of material culture in Innsbruck or Victoria or on the Internet.

I work with sources in Greek, Latin, Provencal, Old French, Ibero-Romance, Middle High German, Old Norse, Irish, and Arabic. That is nine dead languages only two of which I am formally trained in. In later parts I will address Low German and Middle German sources. The only important language I could not cover was Hungarian where I have neither language skills nor a contact who can help (there don’t seem to be dictionaries of Hungarian Latin alas). And just like my medieval research continues a tradition that died a hundred years ago, in a hundred years, when the internet as we know it is long gone, these print articles will survive and be useful.

“Linen Armour in the Frankish Countries, Part 1: The Twelfth Century,” in Cordelia Warr ed., Medieval Clothing and Textiles 18 (The Boydell Press: Woodbridge, 2024) pp. 1-40 is available for anyone who asks for a copy

I also publish for Karwansaray BV‘s print magazines, and have a Patreon post about a medieval Arabian arrow picker. But these are not nearly as much work as an academic article, and don’t have to pass so many gatekeepers.

None of these is open access because putting resources on a website forever is expensive and nobody wants to pay for that in the humanities (I think there is a digital version of Festschrift Rollinger for paying subscribers). But I can send copies to anyone who wants them, and will put copies on my website under My Articles by the end of the year. If you don’t want to ask in a comment here, my email address and Mastodon handle are on my About page.

If I were a galleon, my blog posts and magazine articles would be the swivel guns and murdering pieces sending a hail of shot that makes a lot of noise but does not carry very far. Gunners can swing the muzzle inboard or pop in a new chamber and keep up a steady rate of fire from behind nice solid gunnels, but if the shot does not take your head off you don’t have much to worry about. My books and journal articles are the culverins and perriers that can hurl a lump of iron or limestone for a mile or two to smash a mast or a structural timber after which a ship’s boy has to crawl out along the hot barrel to reload (best to do that downwind of the enemy if they have anyone who can use an arquebus or a Turkish bow). They don’t come out as often, but you can’t forget them as quickly, because sometimes you have to sail all the way home around Ireland in a stormy summer and your ship has so many holes in it that it is being held together by cables and prayers.[1] Some say that a ship with just the great ordinance is the future, or my future, but right now I have a use for both.

Like the Spanish Armada, my supply of smallshot is depleted! Help refill my arsenals with donations on Patreon or elsewhere.

(scheduled 3 April 2025, last updated 12 June 2025)

[1] Yes, I did read Martin and Parker’s Armada (latest edition 2022) as an undergraduate, why do you ask? Chapter 11 of the latest edition reveals the horrid truth about how the Spanish built their gun carriages for sea in 1588. John F. Guilmartin’s Gunpowder and Galleys (1975) is also useful. ⇑

#ancient #medieval #printPublications #shamelessPlug