The Cuisenaire-Gattegno Log Cabin

Rods! Or more specifically, Cuisenaire® Rods! Staples of my childhood arithmetic education: coloured wooden rods (now plastic, which will save them from the mouldy fate that befell some sets at Mearns Primary School), 1 × 1 × 1–10 centimetres long. Use them for counting, number lines, don’t-do-that renditions of Sun Arise, but absolutely never for flinging at tiny classmates.

Since it may actually have been Mrs. Cuisenaire who came up with the concept of rods, I drew a log cabin quilt section in virtual rods. The Gattegno in the title refers to Caleb Gattegno, the mid-century educator who popularized Cuisenaire’s work.

Should you too feel the need to have a virtual set of rods, here are some files you can play with in Inkscape (or any other SVG-aware editor):

rods.svg — A palette of horizontal and vertical rods
rods.svg — A palette of horizontal and vertical rods
rods-quilt.svg - source for the header image
rods-quilt.svg – source for the header image

The colours might be a bit off reality, but they’re near enough. I found it helpful to set a grid snap in Inkscape to 1 cm so that you could get the rods to align easily. If you want to get really nerdy, here’s the PostScript source I used to create the rods: I think I finally got the hang of basic arrays in PostScript …

Creating this was in no way a means of me displacing getting round to doing my taxes this year, nosirree.

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I got my ColorHug calorimeter the other day. You can’t tell, but this laptop display is a bunch warmer than it was, and there are now colours springing out of what was formerly murk (sproing!).

It’s still very much in beta (and I mean that the way it used to mean), so it works but is a bit fiddly. It currently has to boot from a Linux live CD; there’s no native OS X or Windows support. There’s a very active user group, and issues are being found and squished daily.

aahh! they’re messing with my head!

For as long as I can remember (and likely before it), Weetabix has been my breakfast. The familiar yellow box has always been a priority item in the shop:

old weetabix box

But now it’s gone blue!

new weetabix box

How am I supposed to find it now? No other breakfast box had the familiar (and yes, comforting) colour. There is yellow on the box, but it’s different – lighter, less substantial.

If you need me, I’ll be the one in the corner, rocking and emitting small mewling noises.

All the printers I’ve ever owned …

bird you can see: hp print test

  • An ancient (even in 1985) Centronics serial dot-matrix printer that we never got working with the CPC464. The print head was driven along a rack, and when it hit the right margin, an idler gear was wedged in place, forcing the carriage to return. Crude, noisy but effective.
  • Amstrad DMP-2000. Plasticky but remarkably good 9-pin printer. Had an open-loop ribbon that we used to re-ink with thick oily endorsing ink until the ribbons wore through.
  • NEC Pinwriter P20. A potentially lovely 24-pin printer ruined by a design flaw. Print head pins would get caught in the ribbon, and snap off. It didn’t help that the dealer that sold it to me wouldn’t refund my money, and required gentle persuasion from a lawyer to do so.
  • Kodak-Diconix 300 inkjet printer. I got this to review for Amiga Computing, and the dealer never wanted it back. It used HP ThinkJet print gear which used tiny cartridges that sucked ink like no tomorrow; you could hear the droplets hit the page.
  • HP DeskJet 500. I got this for my MSc thesis. Approximately the shape of Torness nuclear power station (and only slightly smaller), last I heard it was still running.
  • Canon BJ 200. A little mono inkjet printer that ran to 360dpi, or 720 if you had all the time in the world and an unlimited ink budget.
  • Epson Stylus Colour. My first colour printer. It definitely couldn’t print photos very well.
  • HP LaserJet II. Big, heavy, slow, and crackling with ozone, this was retired from Glasgow University. Made the lights dim when it started to print. Came with a clone PostScript cartridge that turned it into the world’s second-slowest PS printer. We did all our Canadian visa paperwork on it.
  • Epson Stylus C80. This one could print photos tolerably well, but the cartridges dried out quickly, runing the quality and making it expensive to run.
  • Okidata OL-410e PS. The world’s slowest PostScript printer. Sold by someone on tortech who should’ve known better (and bought by someone who also should’ve known better), this printer jams on every sheet fed into it due to a damaged paper path. Unusually, it uses an LED imaging system instead of laser xerography, and has a weird open-hopper toner system that makes transporting a part-used print cartridge a hazard.
  • HP LaserJet 4M Plus. With its duplexer and extra paper tray it’s huge and heavy, but it still produces crisp pages after nearly 1,000,000 page impressions. I actually have two of these; one was bought for $99 refurbished, and the other (which doesn’t print nearly so well) was got on eBay for $45, including duplexer and 500-sheet tray. Combining the two (and judiciously adding a bunch of RAM) has given me a monster network printer which lets you know it’s running by dimming the lights from here to Etobicoke.
  • IBM Wheelwriter typewriter/ daisywheel printer. I’ve only ever produced a couple of pages on this, but this is the ultimate letter-quality printer. It also sounds like someone slowly machine-gunning the neighbourhood, so mostly lives under wraps.
  • HP PhotoSmart C5180. It’s a network photo printer/scanner that I bought yesterday. Really does print indistinguishably from photos, and prints direct from memory cards. When first installed, makes an amusing array of howls, boinks, squeals, beeps and sproings as it primes the print heads.