Mysterious Files PH

Tuesday, August 25, 2026

Reject Fluid Simulations, Return To Rheoscopic Fluid

August 25, 2026 0

Fluid simulations are one of the “killer apps” of high-performance computing, but if you can’t afford the performance, they can take a depressingly long time to run. Depending on your use case, as long as you keep the Reynold’s number in mind– or are just looking for a qualitative look at pretty flows–you might be able to get away with purely-practical simulations using rheoscopic fluid, as [Visual Thinker] demonstrates in a recent video.

The fluid, as you can guess from the name, lets you scope out rheos— that’s flow, for those of you didn’t take Greek. Making it is as simple as you could ask for: get some mica flakes, which are readily available to add ‘sparkle’ to cosmetics, and mix with water and a drop of soap. The soap isn’t always necessary, but depending on your mica it helps keep it in suspension and avoid clumping– [Visual Thinker] found it helped him a good deal. Being flat plates of reflective material, the mica flakes catch the light and sparkle beautifully– and since they align with the fluid shear, they show you exactly what’s going on in your ‘simulation’.

[Visual Thinker] isn’t starting with serious simulations; the first thing he tries is essentially a toy that lets him see fluid flow around a Benchy by sticking magnets in it and using it to move a cross-section of its hull though a thin layer of fluid sandwitched betwixt pieces of laser-cut acrylic. We don’t call it a toy to disparage it, though– we totally want one. [Visual] mentions the idea of a coffee table combining the concept with the kind of underslung mechanism we see in sand drawing tables, which sounds dangerously hypnotic. If any of you build one, please try and tear your eyes away long enough to let us know.

He has another beautiful piece that make the video worth watching: a wind-tunnel, again made of laser-cut acrylic and printed parts. With careful consideration of the scale and flow speeds, that one might actually prove useful– and even if it doesn’t, it’s pretty enough that it doesn’t really matter. Beauty has its own utility sometimes.

Most wind tunnels we see around here use actual wind, but rheoscopic fluid was invented for this sort of thing, even if it does make for pretty baubles.


Native SMB3 Client Brings Modern NAS Access To 20-Year-Old PowerPC Macs

August 25, 2026 0
Native SMB3 Client Brings Modern NAS Access To 20-Year-Old PowerPC Macs

As software updates cease for operating systems, they eventually begin to lose access to parts of the LAN and internet due to out of date encryption features, as well as the inability to handle file sharing protocols like SBM3, which is somewhat of a necessity if you have e.g. a NAS on the LAN. Such too was the case with [watermark_hd]’s 20-year old PowerPC Macs and their installations of OS X Tiger and Leopard.

Cue Aqualink, a native SMB3 client for these older OS X versions that uses [Ronnie Sahlberg]’s libsmb2 server/client library for SMB2 and SBM3. The source code can be found over on GitHub, along with a Japanese translation. By using a local WebDAV server Tiger’s built-in mount_webdav feature can be used to mount these remote volumes.

While you can often still use SMB1 even on modern Windows and Linux/BSD via Samba, allowing even retro systems like these PowerMacs to speak SMB3 is at least a great boost for network security, even if the aforementioned encryption shortcomings mean that you cannot quite run encrypted file shares yet.

Although OS X eventually began to adopt modern SMB versions, some of us may remember how incredibly buggy they were, to the point that us OS X users often had to fall back to CIFS (SMB 1.0), so this is another potential use for this Aqualink application.


AI Book Scanning: Just What Is A Rare Book?

August 25, 2026 0
AI Book Scanning: Just What Is A Rare Book?

One of the stories of the last few weeks has been that AI companies have been scanning books in very large numbers in order to train their models with content guaranteed to have been written before 2002, and thus AI free. It’s caused some outrage, because of the size of the operation, and because the scanning process is destructive. In particular the phrase being bandied around is that these are rare books, and it’s this phraseology I find problematic. I think it’s time to unpack why that is the case.

It’s Not Book Burning, Folks

Before I worked for Hackaday I had a long career in and around the publishing industry, mostly on the electronic side, but from time to time crossing paths with my colleagues in the world of paper-based publishing. I understand the appeal of a good book, I’ve spend a lot of my life among bibliophiles, and let’s just say I own a few books myself. In particular I understand the symbolism of destroying books, bringing to mind as it does the actions of repressive regimes. I have stood in Bebelplatz in Berlin where the photo of Nazi student organisation members burning the library of Magnus Hirschfeld’s institute was taken in 1933, and if you know me, you’ll have an idea why that’s close to home. But for all that, what the AI companies are doing is not the same thing.

In this case they’re destroying the books for two reasons. Firstly, as I remember from a previous employer in the publishing world, it’s much easier to digitise a stack of papers than it is a bound book. Thus I’m pretty sure that’s one reason they remove the binding before digitising the pages. Then secondly, as I understand it it’s a copyright issue. If they buy a book, digitise it, and destroy the physical copy, they can legitimately claim that only one copy of it exists, and they hope, sidestep copyright claims from publishers.

When Rare Maybe Isn’t Really Rare At All

The ISBN panel with barcode from Bil Herd's Back Into The Storm.
You’ll only see one of these numbers on a book published since 1970.

Perhaps the most pertinent question then is just what are the books being scanned and destroyed? They’re almost universally described as “rare”, but is that accurate or sensationalist? It brings to mind a dusty library filled with priceless tomes hand-transcribed by monks which it would be a crime to destroy, but there’s something that explodes that vision in an instant.

If you read the reports of what’s happening, they are ordering books by ISBN number. That’s an international system for identifying books, which was only introduced in 1970. If they’re ordering a book by its ISBN, it’s no medieval illuminated manuscript.

So the books being scanned and destroyed are relatively new, but can they still be described as rare? In that case just like anything else mass-produced since 1970, how many survive depends on the size of the original print run and how valued they have been since. So a few of these books can be physically rare in the sense of being uncommon, but if they are next-to-valueless, it’s fairly obvious nobody has particularly cared about their survival up to now. It’s likely that any books printed since 1970 which are both rare and of value will have their future assured, so the AI industry is not committing the wanton destruction of culture the reports would like to suggest.

You Need To Know Just How Many Books Get Pulped Every Year

A dumpster full of books
People are often shocked when they find a dumpster full of books for recycling. Ricky Shore, CC BY-NC-ND 2.0.

I’m left feeling that a combination of the symbolism of destroying books along with a distaste for AI companies has inflated the status of these books well beyond their worth. If people truly had a care for old books they would be shocked to know how many are pulped each year by the paper recycling industry.

The publishing industry has been churning out mass-produced books for centuries now, so the world is awash with old books. Where do these newly-minted bibliophiles imagine they all go, to the Great Library In The Sky? I haven’t even touched yet upon the publishing industry, which pulps vast quantities of brand new unsold books every year. Where is the outrage, I ask?

We all love to dunk on AI companies, and Heaven knows, there are plenty of reasons to do so. Among all those reasons, sadly destructively digitising books is pretty low on the list. Please, ask the other questions, the ones they really don’t want to answer!

Header image: Yair Haklai, CC BY-SA 4.0.


Artificial Intelligence as It Once Was

August 25, 2026 0
Artificial Intelligence as It Once Was

One day, people will look back at what we call Artificial Intelligence and laugh. We do the same thing today, as chat bots totally outstrip what the computer industry called AI up until pretty recently. This didn’t escape curators at the Internet Archive, apparently, and [Jason Scott] tells us about a recent collection, “Vintage Artificial Intelligence.”

These are old software titles that will run for you in emulated machines right in your browser, ranging from somewhere in the 1970s to the 1990s. There’s Eliza, of course. Actually, there are several copies of Eliza. Given how simple it was to write Eliza, it did a pretty good job. Then there are adventure games that are pretty conversational, Lisp, Prolog, which was going to spawn expert systems to replace us all, and Racter, which tried to write fiction.

There was even Alter Ego that was supposed to help you explore life decisions, maybe? There are a couple different versions of even a few versions of Conway’s Game of Life. We aren’t sure that’s ever really been AI, but perhaps it depends on your definition. We’re happy to see Sargon, the chess program, represented.

We didn’t see Hexapawn, which is a shame. We also didn’t see Parry (the paranoid counterpart to Eliza) or that elusive software we remember but can never find that built word chains from text called George.

We’ve written about Eliza before. If you want to experiment with Prolog and you like Pokémon, you’ll appreciate this tutorial.


Monday, August 24, 2026

An Electronic Explanation Of 1960s Fuzz Boxes

August 24, 2026 0

It’s likely that even those of us who have never picked up a guitar in our lives will recognize the sound of an electric guitar with a fuzz box effects pedal. The raspy distorted sound has been at the heart of so many very well known recordings. Behind it is a distortion circuit, or as [Bill Jehle’s Mad Scientist Guitar Lab] is here to tell us, eight different circuit topologies.

The result is a fascinating trip through the evolution of rock music through the 1960s, as he examines circuits from simple diode clippers through to frequency doublers and phase shifters. He’s provided a playlist as an accompaniment so you can even have an immediate listen to each sound. It’ll mess up our YouTube recommendations, but worth it for the informative journey.

It’s also a window into a lost period in electronics where all they practically had was the transistor, so each device had to put in the maximum work for a living. Designing circuits like these called for intimate knowledge of the device characteristics, and just how they could be safely exceeded. The video is below the break, and well worth a watch.

If clever transistor music circuits interest you, you’ll love the flawed devices that gave the Roland 808 its sound.


At Last, A Gameboy Advance With Decent Audio

August 24, 2026 0
At Last, A Gameboy Advance With Decent Audio

Many pieces of consumer electronics are build down to a price, and the corners cut show up in their performance. The Gameboy Advance from Nintendo is no exception: its audio is a PWM stream that sounds awful through the included amplifier. [Cajun Panda] has a fix though, in the form of a replacement audio chain.

It takes the form of a PCB that hooks into the pads of the removed GBA audio chip, and provides a much cleaner audio path with filtering and EQ and a class D audio amplifier. In addition there’s an audio codec and an ESP32 for Bluetooth connectivity, enabled by a long press of a GBA button and configured via a web interface on the ESP. Best of all there is no case modification, this is designed to remain as stock as possible.

Everything can be found in a GitHub repository should you wish to make your own, so if you want to bring your GBA audio up to scratch you know where to go. If you want to make it even better don’t forget, you can always upgrade the screen.


Tech in Plain Sight: Vacuum Blood Collection

August 24, 2026 0
Tech in Plain Sight: Vacuum Blood Collection

If you’re blessed enough that you haven’t had blood drawn in a while, you might not have thought much about the process. You might imagine that a needle goes in, a syringe is drawn back, and the venous blood is thusly collected. Indeed, it can be done that way.

However, there is an altogether niftier and more efficient method of fast blood collection for pathology testing. It’s all about using vacuum and smart design to ease the work of phlebotomists, while maintaining a sterile and safe environment.

Vacuum, Contained

These days, if you get blood collected for testing, there’s a plenty good chance you’ll have it drawn into a vacutainer. It’s named as a portmanteau of “vacuum” and “container” because that’s fundamentally what the system relies upon. A vacutainer is a glass or plastic tube which holds a vacuum inside, sealed with a stopper. That vacuum can be used to help extract fluids to be stored inside the container—namely, blood, in most cases.

A blood draw taking place with a vacutainer. The needle unit is inserted into the vein, while the vacutainer tube is slid into the housing to draw blood out. Credit: public domain

The method of use is relatively straightforward. A vacutainer needle is inserted into a patient’s vein to access the blood. The vacutainer needle does not have a typical syringe draw. Instead, the back end of the needle sits inside a plastic housing which accepts vacutainer tubes. There is a flexible rubber seal on the back end of the needle so blood doesn’t leak out when no tube is connected.

When a vacutainer tube is inserted into the housing, the vacutainer needle pierces the stopper of the tube. The vacuum inside then draws blood from the vein into the tube for collection. When full, the tube can be removed and it self-seals as the needle comes out of the stopper. Another tube can be quickly clipped into the vacutainer needle housing to draw further blood if more is needed, without leaks or mess causing contamination issues.

A series of vacutainer tubes filled with blood for testing. The different colored caps indicate different additive content, which preserves the blood under ideal conditions for different types of testing. Credit: Tannim101

Vacutainer tubes are, by design, single use. They’re manufactured to capture a set quantity of blood for testing, based on the level of vacuum in the tube at the time it is sealed, and are disposed of after use. Labels are often included on the tubes allowing patient information to stay with the blood itself. Tubes have a shelf life, as with most medical paraphernalia, in particular since they may not maintain vacuum indefinitely.

The tubes are also typically filled with various additives in order to best preserve and prepare the blood while it awaits testing, and stoppers are color-coded to indicate this. The precise additives used are highly dependent on the testing required. A tube for a standard blood culture draw will typically be filled with sodium polyanethol sulfonate, which acts as an anti-coagulant, with growth media also present for microorganisms.

Coagulation tests will use tubes with sodium citrate inside, while a test for lead will often use a tube with sodium EDTA chelator inside. Some basic blood component tests will use a plain tube with no additives, while others are highly specific—tuberculosis testing often uses purpose-made tubes with antigen additives ready to go. Some tubes include special serum-separating agents which help with splitting blood into its component parts when shaken or centrifuged, useful for certain tests that look at different blood cell types individually.

A package of vacuum blood draw tubes, with the purple cap indicating K2 EDTA additives inside. Credit: via Amazon
A vacutainer needle hooked up to a housing. The needle inside the housing typically has a rubber sheath which stops blood flow when no tube is inserted. This allows tubes to be hot-swapped for drawing multiple quantities of blood from a patient. Credit: via Amazon

If you’ve ever dared to watch while having your blood drawn in this manner, the technology can look quite swish. The tubes are easy to hotswap without leaking any blood and several tubes can be filled in under a minute once the phlebotomist has found an appropriate vein.

However, the technology is not particularly new. It was developed all the way back in 1947 by Joseph Kleiner, though other vacuum-based blood draw techniques existed previously. His goal in developing the technology was to ease patient discomfort and reduce the spillage of blood. This stemmed from his experience seeing his terminally-ill wife suffer multiple needle punctures whenever multiple blood tests were required, and seeing the mess caused when syringes were emptied into test tubes for processing and testing. His inspiration was seeing vacuum-sealed tubes used by the military to transport blood during World War II; the product he developed would later reach the market in 1949. They had the benefit of keeping the blood from exposure to air, reduced the number of punctures required along with the chance of needle stick injuries and infection, and ensured blood was collected in standard volumes and conditions, which aided clinical accuracy. Plastic versions were developed by medical supplier Becton Dickinson in the 1960s, and have become widely popular in the phlebotomy field since.

If you’re not in the medical field, and you’ve managed to avoid regular blood tests, you probably haven’t even noticed vacutainers. Alternatively, you might simply live in an area where their use is uncommon, or you’ve just been intently looking away while your blood has been drawn. In any case, they remain a neat little bit of technology that makes a messy, hazardous, medical process as clean and tidy as possible.

Featured image: “Drawing Test tubes different colors” by [Goldmund100].