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Sunday, 30 August 2015

Posted at 02:36PM under Armchair Linguistics .


Today's request comes from Jess Smith, of Perth, Western Australia. Jess writes:

Please write a blog post about appropriate uses of the semicolon.

Happy to help, Jess! I have a long answer and a short answer for you.

The short answer is this: None at all.

But here's the long answer.

Semicolons are a beast comprised entirely of edge cases. Like most solutions for edge cases they're highly specialized and work very well at what they do - but if you're using one, it's a sign that you're pushing the English language to the very limits of its useful ability, and you should probably consider restructuring instead.

There are two of these cases - that honestly, you should be trying as much as possible to avoid.

The first, and simplest to understand, is lists. Semicolons are an acceptable separator for successive items in a list, particularly if those items in a list are long enough to have the standard separator - that is, commas - as a part of them.

While this is okay, if you're considering using semicolons in this way you should probably look into using something like dot points, or simplifying your list items, or making each item its own paragraph. Because the resulting list is going to be very long and very messy, and quite aside from the semicolons, is going to be quite a chore to read.

The other use of semicolons is in joining two or more independent but related clauses. Let me break this down.

A clause, semantically speaking, is what we call a predicate. It makes a single statement about the state of the world. Grammatically, that means it contains at least one verb to be done, and usually at least one noun to do the doing as well.

Clauses come in two types. Dependent clauses cannot stand as sentences on their own. In a sentence like "The road which runs next to mine is closed for extensive re-surfacing," the "which runs next to mine" is a dependent clause. It contains a verb (runs) and makes a statement about the world (something is running somewhere), but cannot stand on its own. To say "The road is being resurfaced. Which runs next to mine." is not just technically wrong, it looks bloody weird. (Mostly because the verb is missing a subject.)

Independent clauses, on the other hand, can stand on their own. We could correct our statement above by changing it to something like, "The road runs next to mine. It is being resurfaced." Two independent clauses. Both with a subject and a verb. So, two valid sentences.

Enter the semicolon. The semicolon separates clauses which technically could stand on their own as sentences, but which are still closely related to another, also independent, clause. So on our case, it would also be allowable to write, "The road is being resurfaced; it runs next to mine." Note that these are both still independent clauses. If the thing after your semicolon can't stand on its own, it doesn't belong after the semicolon.

These are allowable uses of semicolons. They are almost never, as our question asks, appropriate. Because an independent clause separated by a semicolon is by definition capable of standing on its own as a sentence, it's probably better to just do that instead. And if your clause isn't actually independent at all, then you can't use a semicolon anyway. Either way, if you're even considering using a semicolon, your sentence is probably going to be too long for a regular human to parse easily. It'll be difficult to edit, difficult to restructure, and difficult to read.

Basically, what your writing needs in most cases isn't semicolons. It's better editing.


Tuesday, 25 August 2015

Posted at 06:18PM under 3D Printing .

Scaling New Heights

Here's a fact you probably didn't know: Those plastic bits on the side of pocket knives are called 'scales'.

Aside from lending itself to all kinds of puns, these little plastic widgets are great targets for general hackery.

my scaly mate

This is the Victorinox Escort my dad got me when I turned about 13. Aside from a brief period of carrying the Classic I got for free at some trade show a few years later and subsequently lost at the beach, I've had this knife on my keychain since I was old enough to start having a keychain to put it on.

And a couple of weeks ago, it broke. The back-side scale cracked, without me even noticing, and I lost the toothpick and a chunk of the plastic too.

This is about a fifteen-dollar knife, so I could just replace it (and I did) - but this is the age of computer aided design, of object piracy, of three dimensional printing. And I thought - I can fix this.

Not only can I fix this, but I can make it better.

A dig through Thingiverse turned up a handful of scales for larger knives, proving that a replacement was at least theoretically possible. But there were none for the knife that I had, the 58mm size. I could probably scale (ha.) one down, but then I'd lose the correct sizing of the slots for the toothpick and such.

But then, who says I have to put a toothpick in there at all? If I'm going to have to design this thing from scratch, why not put something else in there instead?

What's a tool I use every day, that lives on a keyring, that I might want to carry around with me at all times, and that fits neatly into something about a centimetre across?

not to scale

Hmm. Verbatim make these fairly nifty little flash drives, which just stick in the bottom part of a USB port. They're really thin, amazingly light, and already come with a little keyring hole to pivot around.

I can work with this.

scaled up

Right in the middle of a dinner party, I make a few measurements to the closest millimetre. The whole point of 3D printing is that you can prototype, and something this small will only take about 10 minutes to build. I can tweak the design after each iteration, until it's perfect. I steal some time on a computer, throw together a design in Tinkercad, and go back to my soup.

About a week passes, and when I get back to work, they tell me that the 3D printers aren't working.

No worries. We can iterate on that at the same time.

scalar quantities

Eventually I fix - well, "fix" - them, after about two solid days of frustration, by dropping the extruder temperature by about 10 degrees, and covering the build platform in masking tape. And what do you know, the first one off the bed... doesn't fit. But only barely. The void needs to be about a millimetre longer.

And it turns out, that's the only change I actually needed to make. The drive fits perfectly, but the knife is at home. I walk home via Officeworks, and pick up a new drive in a matching colour. Also, some superglue. I included snap-on style holes for the knife's internal rivets, but I'd like something a little more adhesive actually holding the scale on there.

scaled composites

I get home and lay out my materials...

the scales tip in my favour

...try the scale on the knife...

the scales tip in my favour

...and they fit!

Not just reasonably, but beautifully. Turns out my eyeballing was better than expected.

And a little bit of glue in each of the rivet holes finishes it up.

Some product action shots:


If you want to give this a shot yourself...

Tinkercad - Solid & USB versions.

And Thingiverse.


Thursday, 20 August 2015

Posted at 02:47PM under Technical Stuff .


tl;dr: some new web and email addresses. read my science blog. you do not need to change anything, continue to be rad.

So there are a couple of things which have changed around here which I should've already mentioned.

First: This blog has moved. It's moved to a subdirectory of my actual website, which quite frankly, is where it should have been all along. The only reason it wasn't is that my blog engine was rather poorly written, and couldn't actually do that. It's improved over the last almost-three years to the point where - totally because of miscellaneous other improvements - I realised it actually could.

There is some rewrite magic in place to redirect all previous links to It will even preserve permalinks to individual pages and searches and feeds and stuff. I don't anticipate that these redirects will ever stop working, but I guess just take note of the new address anyway.

This lets me do something else which I've meant to do for a while - convert the whole site to https, without having to buy two separate certificates. Which, as you can see from the little lock icon in your browser, I have now done. This is good for security and whatnot, but it's mostly because a lot of web services won't even give you the time of day without TLS, and this lets me play with all sorts of cool things like chat bots.

Second: I have a new email address.

I honestly thought I'd told everyone about this already a few months ago, and everyone was sick of it, and I was sort of shutting up about it. Turns out what I'd actually done is tell the same two or three people about it over and over, and this came as a surprise to pretty much everyone.

It's a pretty clever domain hack on my last name, which is why I was kind of gushing about it.

sorry about the image. gotta keep those spambots away though...

It's hosted with Fastmail. Which, yes, means I am paying for email like it's the 90s. Unfortunately, Microsoft and Google have both discontinued their free BY0-domain option, and if I'm going to pay some change every month I'd rather it was to a smallish Aussie company which might actually give a crap about my privacy. Plus, their webmail is so fast. Like happily shuffling 10 years of archives around in under a second fast. Like continuous, non-paginated scrolling through that archive fast. The extent to which Google does not care about their web interface is suddenly painfully obvious.

Anyway. As above, you shouldn't need to change anything. My old address(es) will continue to work, but the whole idea of this one is to have something that's not attached to a @gmail or @hotmail, that I can pretty much hang onto for the rest of my life regardless of what underlying service is powering it.

The third thing is: I have a science blog! I post to it very erratically. Mostly as practise, but we'll see where it goes. You should check it out. It's at

That was long and boring, but it sort of needed to be done.


Saturday, 08 August 2015

Posted at 11:02PM under IRL .

The Cloud

"I work inside a machine whose explicit purpose is to simulate a perfect night sky, and this is the most beautiful sky I have ever seen."

"I think I'm going to wet myself."

The galaxy arced overhead as we crunched across the gravel away from the house. An hour ago it had been raining- and overcast- and only a chance trip outside to avoid a somewhat overfed fire had let us know the stars were out at all.

We chose damp backs over strained necks and lay down in the dirt.

"So what are we looking at."

"Well, okay. That's the Milky Way. And you see - there's this kind of fish-hook shape?"


"It goes right down into the middle of the galaxy, that bulgy bit."

"Wait, no."

"Never mind. I wish I had my laser pointer right now."

Attempting to use a torch to do the same thing was spectacularly unsuccessful, and ended in shouts of wrecked night vision all around.

"Hey guys, have you seen this app?"


"No, really. It's pretty great."

"Mine is better."

This cued several minutes of fidgeting with apps, and at least one begrudging trip back to a homestead which - relatively - was as bright and hot as the surface of the sun to grab an app which sucked a little less off a phone that sucked a little more. Was it worth it?

"Oh! That fishhook."


"Right. So you see off the end of that shape, there are some sticky-outy bits? That's Scorpius, the scorpion. And the sticky outy bits are his pincers."

"I see it!"

"But that's not the cool bit. Just off the end there, there's a yellowish star that's not twinkling. See it?"




People arrived and departed, each shaft of torchlight bringing shouts of irritation from the array on the ground. Someone dug up a particularly thorny question about why the sky was dark at all if there were stars in every direction, and nobody seemed able to give an entirely satisfactory answer - though the square-cube law was mentioned at least once. In retrospect that lack of answer seems poignant and imbued with mystery and wonder, but at the time it was mostly just annoying.

"Where's the Southern Cross?"

"Behind that gum tree. You can see the pointers though."

This jogged an archived memory.

"You know, it's probably dark enough to see the Magellanic Clouds."


"Dwarf galaxies, orbiting the Milky Way. It should be dark enough out here to actually see them with the naked eye, but... I think they're over behind those trees."


A little more interest would've been nice. Oh well.

I crunched down the hill, and got my bearings. Down from the Milky Way, up from the horizon, right near the top of that massive triangle - if that was even the right triangle.

And I saw it. Not spectacular. Not beautiful. Really just a smudge, to the left of an unremarkable star, with a habit of vanishing when looked at directly.

But that smudge on my retina was happening because of light that was 200,000 years old. Light from another galaxy - albeit a galaxy gravitationally bound to our own. An island universe of hundreds of millions of stars shining together.

And that light was hitting my eyes. Somehow, buried at the bottom of a thick blanket of 78% nitrogen in the middle of a well-lit corner of the galactic neighbourhood, that light was hitting my eyes.

I wish I could say something poetic about how those eyes filled with tears of wonder, but they didn't. I gawked for a bit longer, and then headed back to a house that now seemed even more impossibly bright and hot than it had before, filled with a vague sense of satisfaction.

And, okay, yes: Just the tiniest bit of cosmic awe.

the sky


Tuesday, 28 July 2015

Posted at 11:07PM under IRL .

New World Order

I wake up at 7:15 every day, which is exactly an hour before I have to leave the house. I grab a shower and some muesli with fruit and yoghurt, and take the 8:28 train to work. Lunch is a toasted sandwich, an apple, and a muesli bar. I make a habit of reading on the train rather than thumbing my phone. Very occasionally - so, at least once or twice a month - I miss my train because I wasn't paying attention to the time, and have to drive to work. Then I'll invariably forget that I did so, neglect to put a permit on my dash, and then miraculously dodge a ticket. On Sundays I have to drive, because there's no train early enough to get me to work on time. I don't mind, because the traffic isn't as bad. Mondays are date nights, Wednesdays are D&D, usually at the Generic Share House. Midnight is my rough bedtime. Anything after that is "late" - ironically - and will be paid for tomorrow morning. My phone theme is crimson, and has been for the last six months.

I have alarms with emoji in them, to tell me how to get to work. On bike days I pretty much grab some toast and leave, and shower at work. I keep some breakfast at work too - it's oats. On train days, I get up a bit later and have tea and muesli that's been warmed up. I shower after breakfast, and have taken to cleaning my teeth at the same time. I know this saves exactly no time, but it means I get to spend longer under the hot water, and it incentivises fresh breath. I abandoned lunchbox muesli bars when I realised in the shops one day that I was seriously considering having peanuts bound with peanut butter and coated in chocolate as a snack. I take extra fruit now instead, which is good, because there's a reasonably priced fruit and veg place on my bike to work. It's closed Mondays though, and somehow that's always the day I run out of fruit. I don't know if I'm ignoring my car out of sheer bloody-mindedness or just because the check engine light is on. Mondays and Wednesdays are still date night and D&D, but with semester starting soon, that will probably change. My phone theme is emerald, and probably will be for the next six months.

Things aren't better or worse, but they are different.

I don't know how or why, but somehow in the last few weeks the background radiation of my life has changed. It doesn't feel like a fad; these cascading insignificant changes have the texture of permanence to them. I'm settling into a new local minimum, an alternative main sequence, and I'm not sure I can go back. So I'm writing down the way things used to be, and what they've changed to, so that when I'm ninety and all of my hair is falling out I can remember what butterfly effected changes in the background chaos led me to where I am now.

i really dig the symmetry here, and i deliberately avoid adding any alarms between them


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