No, you’re not dreaming, that is a blue Menorahcorn decoration on the lawn across the way. 🕎🦄🤩
Brodart has recently discontinued their salmon card index cards with pre-drilled holes #23-188-218. This has been a shift since the summer of 2025, though they’re still carrying the standard salmon index cards (without predrilled holds for card catalog rods).
A conversation with their customer service team seems to indicate there aren’t plans for discontinuing their other cards (blue, green, ivory, white, and buff), but: caveat emptor as they no longer list their card catalog furniture or their charging trays on their website, their Dewey Decimal tabbed cards are now gone, and Demco recently quit carrying their buff/red-lined Library of Congress cards this past year.
Incidentally, they’re doing a 20% discount on their index cards (and related circulation supplies) for the holidays right now, so stock up if you need them.
In honor of Melvil Dewey’s 174th birthday yesterday, I’ve just purchased 6,000 cards in an attempt to get them to continue stocking them all and to have a happier 2026.
Keep your A6 notebooks, pens, and essentials organized on the go with the Field Folio A6. Durable, vegan waxed canvas, slim design, and flexible pockets—perfect for travel, journaling, or everyday carry.
I recently asked the kind folks at Lochby “if the Folio A6 will comfortably fit 25-50 standard 4 x 6″ index cards which are slightly larger than an A6 notebook? If not, is it something you might consider for some of us ‘Hipster PDA’ tribe members in the future?”
Erring on the side of caution their customer service replied, “Unfortunately, since the Field Folio A6 zips up, there’s no way to fit this many index cards in it without the potential for damaging them when zipping it up. But I’ll take note of your suggestion and pass it on to our product development team so we can consider it as well as gauge interest.”
Because I often use A6 sized notebooks, I couldn’t resist adding to my Lochby collection, so I went ahead and ordered it anyway.
It arrived in the post yesterday. Today I’m happy to report that it actually will accommodate 4 x 6″ index cards reasonably well. I can comfortably fit about 30 cards into the right side pocket and still have room to tuck a Hobonichi A6 notebook into the folio and still zip it shut handily.
Because I usually have a few pre-glued decks of index card “notebooks” sitting around, I tried one of these and can happily report that the back cover/board fits into the right pocket easily (just as you’d tuck the back cover of a notebook into it) and works well with the Lochby A6 folio! (The center elastic bands are slightly smaller and fairly tight, and could work with these glued decks too, but will tend to cut the glue at the ends, so one should take care here or carefully only glue the center 5 inches of the deck for this use case.) I suspect that if one had a plastic wallet-photo type holder, it might work well in this, particularly if you’re carrying around some of your daily use cards in addition to blank cards for future use.
Fundamentals Of Hypercomplex Numbers | UCLA Extension
Dr. Michael Miller, a retired researcher at RAND, has been teaching upper level undergraduate/graduate level math courses for fun at UCLA Extension for over 50 years. This winter, he’ll be introducing hypercomplex numbers to those interested in abstract math: Fundamentals Of Hypercomplex Numbers.
His courses are thorough and rigorous, but geared toward lifelong learners and beginners in abstract mathematics to allow people better entry points into higher level mathematics. His classes are interesting and relatively informal, and most students who take one usually stay on for future courses. The vast majority of students in the class (from 16-90+ years old) take his classes for fun and regular exposure to mathematical thought, though there is an option to take it for a grade if you like. There are generally no prerequisites for his classes, and he makes an effort to meet the students at their current level of sophistication. Some background in calculus and linear algebra will be useful going into this particular topic.
If you’re in the Los Angeles area (there are regular commuters joining from as far out as Irvine, Ventura County and even Riverside) and interested in joining a group of dedicated hobbyist and professional mathematicians, engineers, physicists, and others from all walks of life (I’ve seen actors, directors, doctors, artists, poets, retirees, and even house-husbands in his classes), his class starts on January 6th at UCLA on Tuesday nights from 7-10PM.
If you’re unsure of what you’re getting into, I recommend visiting on the first class to consider joining us for the Winter quarter. Sadly, this is an in-person course. There isn’t an option to take this remotely or via streaming, and he doesn’t typically record his lectures. I hope to see all the Southern California math fans next month!
Course Description
A survey of those systems of numbers that can be constructed by adding “imaginary units” to the real numbers. The simplest and most familiar example is the two-dimensional system of complex numbers. Much less familiar, but equally fascinating, are the systems of quaternions and Cayley numbers, of dimensions four and eight, respectively. These “algebras” still enable meaningful notions of addition, multiplication, and division, but only at a price: the loss of commutativity and (in the case of Cayley numbers) associativity. Things get even more bizarre when sedenions (dimension 16) and trigintaduonions (dimension 32) are brought into play. The latter part of the course is devoted to the theorems of Hurwitz and Frobenius on the existence of suitably behaved division algebras over the real numbers.
The course should appeal to those seeking a better understanding of the arithmetical underpinnings of our number system.
Prerequisites: advanced calculus and linear algebra
January 6 – March 17
Tuesday 7:00PM – 10:00PM PT
REG# 407060
Fee: $450.00
Recommended textbook: TBD
Register here: https://www.uclaextension.edu/sciences-math/math-statistics/course/fundamentals-hypercomplex-numbers-math-900
If you’ve never joined the class before (Dr. Miller has been teaching these for 53 years and some of us have been with him for nearly that long; I’m starting into my 20th year personally), I’ve written up some tips and hints.
I now have definitive written proof of a numeric indexing system (delineated in a popular textbook for secretaries, and published by a company which did significant business in Germany) from the mid-1920s with increasingly more detail into the 1940s and a fifth edition published in 1950. It’s exactly like, but notably predates, Niklas Luhmann’s alphanumeric system which he started in 1952. I’ll write up some of the details shortly with specific references, but thought I’d tease it here a bit first.
While digging about in indexing and filing systems, I ran across this chart created by the Oxford Filing Supply Company for a special Filing Supplies section of the May 1934 issue of Office Appliances magazine (Volume 59, Issue 5). It delineates the broad characteristics of most of the major commercially available filing systems of the era.
Of course, by itself, it may not make much sense, so for those interested in older indexing and filing systems, take a peek at Remington Rand’s textbook Progressive Indexing and Filing (1950) which provides lots of images, examples, and full descriptions by many of the bigger manufacturers.
Perhaps these, which are all fairly similar, may help someone in designing their indexing system for a zettelkasten or commonplace book practices.
The rest of the articles in the magazine also have some fascinating history.
Zettel of the Year Awards
In preparing for some of my end-of-the-year review from my card index, I thought it would be interesting to choose the “Best Note of the Year”. Then it thought it might be worth choosing a “Best Insight”, “Most Surprising Note”, and a “Best Folgezettel” as well.
And if you’re going to give out an award, it should involve a trophy of some sort, right?!? So naturally I went out and picked up a “4 x 6 inch index card” made out of India Black Granite that I plan on engraving with the Note of the Year. At 3/8ths of an inch thick, it is by a large stretch the thickest index card I have in my zettelkasten.
As it may be an interesting end-of-year review practice, I thought I would open up the “competition” to others who’d like to participate. Are there other categories one should enter cards for consideration?
What is your “Best Note of the Year”?
The third ever IndieWebCamp San Diego with two days of independent open distributed web talks, breakouts, and hack sessions. Bring your website or setup a new domain on the spot.
This has been one of my favorite events for the past two years, and after a rough 2025, this is a great way to cap off the year.
Even better, Tantek has already suggested a session on card catalogs that’s right up my alley: https://indieweb.org/2025/SD#Session_ideas.
An early 21st century textbook on filing and indexing practices geared toward office workers. First edition, 1932.
The first section is on the rules of alphabetization and indexing to standardize the space of ordering cards for both people’s names and company names.
The second section covers some history on basic filing techniques and then goes into alphabetic, geographic, numeric, and subject indexing methods. The final sections cover the L.B Automatic (Library Bureau), the triple check method, and various other special filing methods as well as maintaining and transferring files for long term storage. Illustrations of these various methods help to visualize how they worked in practice.
This text isn’t as interesting or as comprehensive as the works of J. Kaiser from earlier in the century.
Read on 2025-11-16.
Watching people online chat, ask questions, and generally get excited about their planners for 2026, I thought I would spend a few minutes to set up my Memindex-inspired planner version using 4 x 6″ index cards and tabbed dividers. It’s amazing how useful a $2.50 block of 500 index cards can be for planning out your coming year.
Interestingly, I’ve recently come across versions of this same sort of tickler file recommended in mid-20th century textbooks for filing and indexing in business contexts:
Cadwallader, Laura Hanes, and Sarah Ada Rice. 1932. Principles of Indexing and Filing. Baltimore; Chicago: H.M. Rowe Company. page 134: https://archive.org/details/principlesofinde0000laur/page/134/mode/2up
Kahn, Gilbert, Theo Yerian, and Jeffrey R. Stewart, Jr. 1962. Progressive Filing and Records Management. 1st ed. New York: Gregg Publishing Division, McGraw-Hill Book Co., Inc. page 190: https://archive.org/details/progressivefilin0000gilb/page/190/mode/2up
The careful observer will notice that both of the photos in texts by different authors nearly 30 years apart are the same! I would suspect that they’re from a manufacturer’s catalog (Remington Rand) earlier in the century. It’s even more interesting that one can still quickly create such a set up with commercially available analog office supplies now.